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1

Wilson, Dallas James Patterson David J. "Comparison of controlled internal drug release (CIDR)-based protocols to synchronize estrus and facilitate artificial insemination (AI) in postpartum beef cows." Diss., Columbia, Mo. : University of Missouri--Columbia, 2008. http://hdl.handle.net/10355/5687.

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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed on October 6, 2009) Thesis advisor: Dr. David J. Patterson, Includes bibliographical references.
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2

Stutts, Kyle Jeffrey. "Synchronization of follicular wave emergence, luteal regression, and ovulation for fixed-time artificial insemination in beef cows and heifers." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4208.

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Two experiments tested the efficacy of gonadotropin-releasing hormone (GnRH) or estradiol cypionate (ECP) administration in combination with controlled internal drug release (CIDR) inserts on pregnancy rate to fixed-time artificial insemination (FTAI) in beef heifers. In the first experiment, heifers in the two ECP groups received ECP in conjunction with the CIDR insert. The CIDR insert was removed and PGF was administered on either d 7 or 9. Heifers received ECP 24 h after CIDR removal and were inseminated 30 h after ECP. Heifers in the two GnRH groups received GnRH in conjunction with the CIDR insert. Heifers received PGF on either d 6 or 7, and the CIDR insert was removed on d 7. Heifers were inseminated and received GnRH 48 h after CIDR removal. Pregnancy rates to FTAI were higher for heifers treated with GnRH. Pregnancy rate to FTAI was highest for heifers in the GnRH group that received PGF on d 6 and was lowest for the group that received ECP in combination with a 7-d CIDR insert. In the second experiment, heifers received GnRH in conjunction with the CIDR insert. CIDR inserts were removed and PGF was administered on d 7. Heifers were inseminated 60 h later, with one group receiving GnRH at insemination. Pregnancy rate to FTAI was higher for heifers that received GnRH at insemination. The final experiment tested the efficacy of estradiol 17_ (E17) or GnRH in combination with a CIDR insert on pregnancy rate to FTAI in Brahman cows. Either E17 or GnRH was administered in conjunction with the CIDR insert. CIDR inserts were removed on d 7. Cows in the GnRH group received PGF on d 6 and GnRH at insemination which occurred 48 h after CIDR removal. Cows in the E17 group received PGF on d 7, E17 24 h later, and were inseminated 30 h after E17 administration. Pregnancy rate to FTAI was higher for cows treated with E17. These data indicate acceptable pregnancy rates were obtained when the CIDR insert was combined with either GnRH in beef heifers or with E17 in Brahman cows.
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3

Saldarriaga, Lopez Juan Pablo. "Ovarian and hormonal events during synchronization of ovulation and timed appointment breeding of Bos indicus-influenced cattle using intravaginal progesterone, GnRH and prostaglandin F2(alpha)." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4733.

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Objectives were to 1) evaluate the use of the CO-Synch + CIDR (COS-C) protocol for synchronization of ovulation and timed AI (TAI) in Bos indicus-influenced cattle, 2) compare cumulative pregnancy rates after COS-C synchronization and TAI to those in a traditional management (TM) scheme, and 3) evaluate specific ovarian, hormonal, and estrual events associated with COS-C. The COS-C regimen included insertion of a controlled internal drug release device (CIDR) containing progesterone and injection of GnRH (GnRH-1) on day 0, removal of the CIDR and injection of prostaglandin F2a (PGF on d 7, and injection of GnRH (GnRH-2) and TAI 48 h later. In experiment 1 (Exp. 1), 335 females were stratified by BCS, parity and d postpartum before random assignment to COS-C or TM. An additional 96 females in which TM controls were not available for comparison also received COS-C. Conception rates to TAI averaged 39% (n = 266). Cumulative pregnancy rates were greater (P < 0.05) after 30 and 60 d of the breeding season in COS-C than in TM (n = 170 and 165 females respectively). In experiment 2 (Exp. 2), 100 postpartum (F1) females were stratified as in Exp. 1 within four replicates (25 each) and assigned randomly to receive either COSC or COS (no CIDR) treatment. No differences were observed between treatments and all data were pooled. Percentages of cows ovulating after GnRH-1, developing a synchronized follicular wave, exhibiting luteal regression to PGF, and ovulating to GnRH-2 were 40, 60, 93, and 72%, respectively. In experiment 3 (Exp. 3), primiparous (F1) heifers (n = 32) and pluriparous cows (n = 18) received the Select Synch + CIDR synchronization regimen (no GnRH-2 or TAI). Mean intervals from CIDR removal to estrus and ovulation, and from estrus to ovulation were 70 ± 2.9, 99 ± 2.8, and 29 ± 2.2 h, respectively. Relatively low TAI conception rates (< 50%) were attributed to failure of 40% of cattle to develop a synchronized follicular wave after GnRH-1 and to inappropriate timing of TAI/GnRH-2. It may be possible to improve TAI conception rates by delaying TAI/GnRH-2 to between 66 and 72 h, and by developing methods to increase the number of ovulations after GnRH-1.
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4

Holm, Dietmar Erik. "The economic effects of an oestrus synchronisation protocol using prostaglandin and reproductive tract scoring in beef heifers in South Africa." Electronic thesis, 2006. http://upetd.up.ac.za/thesis/available/etd-05042007-162414/.

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5

Nelson, John Stephen. "Fixed-time insemination of porcine luteinizing hormone-treated superovulated beef cows and the resynchronization of beef cows for fixed-time embryo transfer." [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-3239.

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6

Holland, Sarah C. "Comparison of Luteolysis and Timed Artificial Insemination Pregnancy Rates after Administration of PGF2a in the Muscle or the Ischiorectal Fossa in Cattle." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/56575.

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Prostaglandin F2α (PGF2α) is commonly given to female cattle intramuscularly (IM) for the synchronization of estrus. A novel site for administration of PGF2α that improves beef quality assurance is the ischiorectal fossa (IRF). The objective of this study was to determine whether administration of PGF2α in the IRF results in a similar physiologic response to administration of PGF2α given IM. Yearling angus-cross heifers (n=112) were blocked by weight and randomly assigned within blocks to be injected with 5 mL PGF2α either IM in the neck or in the IRF. Blood samples were taken at 0, 8, 16, 24, 36, and 48 h post-injection. Serum samples were analyzed for progesterone concentration using a radioimmunoassay. Progesterone concentration curves for each heifer were plotted to determine luteolysis. The median times to luteolysis for neck and IRF injections were 18.1 hrs and 20.0 hrs, respectively (p=0.06). Angus cross commercial beef cows (n=1471) at least 30 days post-partum were blocked by age and randomly assigned to be injected with 5 mL PGF2α either IM in the neck muscle or in IRF as part of a 7-Day CO-Synch + CIDR ovulation protocol. Pregnancy diagnosis was performed via ultrasound at 60 days post insemination. Results were analyzed with Proc Glimmix (SAS). Pregnancy rates for neck and IRF injections were 52.6% and 57.2%, respectively (p=0.06). In summary, injection of PGF2α in the IRF for estrus synchronization and lysis of the corpus luteum did not differ from injection in the neck muscle. Utilizing the ischiorectal fossa as an injection site for PGF2α may be considered as an alternative that more closely aligns with beef quality assurance objectives.
Master of Science
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7

Silva, Aydison Takiguchi Nogueira [UNESP]. "Efeito de diferentes estratégias de manejo reprodutivo em vacas de corte mestiças paridas." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/96639.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
O ex FAO perimento foi realizado durante a estação de monta 2004/2005, em uma fazenda comercial de bovinos de corte, localizada em Água Clara-MS, Brasil. O objetivo foi avaliar estratégias de manejo reprodutivo em matrizes de corte cruzadas paridas. Durante o período experimental foram avaliadas cinco estratégias de manejo reprodutivo: T1: monta natural (n=143), T2: IA e repasse com touros (n=143), T3: IA após sincronização do estro e repasse com touros (n=145); T4: IATF e repasse com touros (n=144) e T5: IATF seguida de observação de cio de retorno (17 a 25 dias) e após repasse com touros (n=149). A estação de monta teve a duração de 70 dias para o T5 e 100 dias para os tratamentos 1, 2, 3 e 4. Os manejos reprodutivos influenciaram (P<0,05) a porcentagem de prenhez por IA (73,7; 67,2; 47,2 e 68,5 %, para os tratamentos 2, 3, 4 e 5, respectivamente). A porcentagem de matrizes gestantes ao final da estação de monta foi influenciada (P<0,05) pelos tratamentos e pela ordem de parição, sendo de 92,3; 89,5; 82,7; 96,5 e 91,3, respectivamente para os cinco tratamentos. Foi observado efeito dos tratamentos (P<0,05) no IEP (400,6; 398,9; 393,6; 381,8 e 374,0) e nos dias para parir (54,0; 50,0; 42,0; 23,0 e 21,0), respectivamente. A ordem de parição, o sexo do bezerro e as estratégias de manejo reprodutivo influenciaram (P<0,05) o peso bezerros a desmama. A IATF permite emprenhar mais vacas no início da estação de monta, reduzindo os dias para a parição e o IEP, permitindo a redução do período de estação de monta. Associado a IATF, a observação de cio do retorno (17 a 25 dias), permite a produção de mais bezerros por IA.
The experiment was conducted during the 2004/2005 breeding season, in a commercial beef farm, located in Água Clara-MS, Brazil. The objective was to evaluate different strategies of reproductive management in crossbred beef postpartum cows (Brangus x Nelore). Five strategies were evaluated: T1: natural service (n=143), T2: AI after heat detection (n=143), T3: AI after estrous synchronization (n=145), T4: Timed AI (n=144) e T5: Timed AI plus AI in cows detected in heat 17 to 25 days latter (n=149). The breeding season lasted 70 days for T5 and 100 days for treatments 1, 2, 3 and 4. The reproductive managements affected (P<0.05) the pregnancy rate per AI (T1= 73.7; T3= 67.2; T4= 47.2 and T5= 68.5%). The percentage of pregnant cows at the end of the breeding season was affected (P<0.05) by treatment and parity (92.3; 89.5; 82.7; 96.5 and 91.3%), respectively for the five treatments. Effect of treatments were observed (P<0.05) on interval between parturitions (400.6; 398.9; 393.6; 381.8 and 374.0 days) and days to calving (54.0; 50.0; 42.0; 23.0 and 21.0 days), respectively. Parity calf sex and strategies of reproductive management affected the body weight of the calve at weaning. Timed AI allows that more cows get pregnant at the beginning of the beeding season, reducing days to calving and interval between parturitions, reducing the breeding season period. Associated to timed AI, detection between days (17 to 25) after timed AI increased number of calves born to AI.
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8

Figueiredo, Eliana Valéria Covolan [UNESP]. "Avaliação de custos econômicos e energéticos de novas tecnologias de inseminação artificial na reprodução de bovinos de corte raça Nelore." Universidade Estadual Paulista (UNESP), 2004. http://hdl.handle.net/11449/101711.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
A bovinocultura de corte é de reconhecida importância no agronegócio brasileiro (mercado interno e externo), sendo que o país tem o segundo rebanho bovino mundial, com cerca de 80% destinados a produção de carne (maioria de zebuínos). Um dos limitantes desta atividade é a reprodução dos animais, que permite que o rebanho cresça em número e qualidade. Atuando-se sobre a reprodução, pode-se melhorar a conversão alimentar, diminuindo o custo. A inseminação artificial (IA) tem grande importância na obtenção de ganhos quantitativos e qualitativos (e.g. ganho genético), além de permitir um melhor controle do rebanho. Novas tecnologias de inseminação estão sendo aperfeiçoadas, inclusive tratamentos hormonais que possibilitam a IA com tempo fixo (IATF). Considerando a questão energética, é importante o desenvolvimento de tecnologias que otimizem os gastos energéticos na bovinocultura. Este trabalho tem por objetivo avaliar os custos econômicos (valores em reais, julho de 2003) nos manejos reprodutivos: IA convencional (IAC), IATF (GnRH-PGF2 -GnRH, GnRH-PGF2 -BE), GP (controle, GnRH-PGF2 e IA) e Monta; em vacas Nelore (zebuínos), além de fazer considerações sobre o gasto energético biológico destes manejos. A partir de dados obtidos em uma fazenda comercial da região de Botucatu, SP, foram realizadas análises de custos de reprodução de bezerros, nas tecnologias de IAC, IATF (grupos GPG-9, GPG-12, GPE-15 e GPE-18) e GP (GP-21 e GP-24) associados à Monta; e Monta-Simulado. O melhor Custo Total Unitário de reprodução por bezerro (CTU) foi observado na IAC (R$ 127,00) com taxa de prenhez (TxPr) de 84%. Na IATF, o melhor resultado foi do grupo GPE-15 (R$ 130,00, TxPr 74%)...
Beef cattle is a very important sector in Brazilian agribusiness, both in domestic and international market. Brazil has the second largest bovine herd in the world, with 80% of beef cattle (mostly Bos indicus). A limiting factor of this activity is the animal reproduction, which allows herd improvement and growth. Acting on reproduction may allow improvements on feed conversion, diminishing costs. Artificial insemination (AI) is a way of obtaining quantitative and qualitative gains (genetic improvement), in addition to a better herd management. New technologies on AI are been developed, including hormonal treatments which allow timed fixed AI (TAI). Besides, on the energetic approach, the development of new technologies optimizing energy expenses is also very important. The aim of this study was to evaluate the economic costs (in Reais, July 2003) on several reproductive handlings: Conventional AI (IAC), Timed AI (TAI; GnRH-PGF2 -GnRH; GnRH-PGF2 -BE), Synchronized estrus GP (control, GnRH-PGF2 and AI) and Natural Service; in Nelore cows (Bos indicus), in addition to making short considerations regarding energetic expenses on those handlings. Reproduction costs analysis were performed on data obtained on a commercial farm in Botucatu, SP, on IAC and TAI (groups GPG-9, GPG-12, GPE-15 and GPE-18) and GP (GP-21 e GP-24) associated to Natural Service; and simulated Natural Service group. The best total reproduction cost per calf (CTU, R$ 127,00) was observed in IAC with the pregnancy rate (TxPr) of 84%; otherwise, in TAI, the best result was from GPE-15 (R$ 130,00, TxPr 74%). The simulated Natural Service group had a CTU of R$ 116,00, with TxPr of 87%. The other groups obtained CTUs of R$163,00 (GPG-12, TxPr 69%), R$174,00 (GPE-18, TxPr 68%), R$181,00 (GP-21, TxPr 59%), R$ 189,00 (GPG-9, TxPr 67%) e R$ 338,00 (GP-24 TxPr 31%)...(Complete abstract click electronic access below)
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9

Silva, Aydison Takiguchi Nogueira. "Efeito de diferentes estratégias de manejo reprodutivo em vacas de corte mestiças paridas /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/96639.

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Orientador: José Luiz Moraes Vasconcelos
Banca: Pietro Sampaio Baruselli
Banca: Henrique Nunes de Oliveira
Resumo: O ex FAO perimento foi realizado durante a estação de monta 2004/2005, em uma fazenda comercial de bovinos de corte, localizada em Água Clara-MS, Brasil. O objetivo foi avaliar estratégias de manejo reprodutivo em matrizes de corte cruzadas paridas. Durante o período experimental foram avaliadas cinco estratégias de manejo reprodutivo: T1: monta natural (n=143), T2: IA e repasse com touros (n=143), T3: IA após sincronização do estro e repasse com touros (n=145); T4: IATF e repasse com touros (n=144) e T5: IATF seguida de observação de cio de retorno (17 a 25 dias) e após repasse com touros (n=149). A estação de monta teve a duração de 70 dias para o T5 e 100 dias para os tratamentos 1, 2, 3 e 4. Os manejos reprodutivos influenciaram (P<0,05) a porcentagem de prenhez por IA (73,7; 67,2; 47,2 e 68,5 %, para os tratamentos 2, 3, 4 e 5, respectivamente). A porcentagem de matrizes gestantes ao final da estação de monta foi influenciada (P<0,05) pelos tratamentos e pela ordem de parição, sendo de 92,3; 89,5; 82,7; 96,5 e 91,3, respectivamente para os cinco tratamentos. Foi observado efeito dos tratamentos (P<0,05) no IEP (400,6; 398,9; 393,6; 381,8 e 374,0) e nos dias para parir (54,0; 50,0; 42,0; 23,0 e 21,0), respectivamente. A ordem de parição, o sexo do bezerro e as estratégias de manejo reprodutivo influenciaram (P<0,05) o peso bezerros a desmama. A IATF permite emprenhar mais vacas no início da estação de monta, reduzindo os dias para a parição e o IEP, permitindo a redução do período de estação de monta. Associado a IATF, a observação de cio do retorno (17 a 25 dias), permite a produção de mais bezerros por IA.
Abstract: The experiment was conducted during the 2004/2005 breeding season, in a commercial beef farm, located in Água Clara-MS, Brazil. The objective was to evaluate different strategies of reproductive management in crossbred beef postpartum cows (Brangus x Nelore). Five strategies were evaluated: T1: natural service (n=143), T2: AI after heat detection (n=143), T3: AI after estrous synchronization (n=145), T4: Timed AI (n=144) e T5: Timed AI plus AI in cows detected in heat 17 to 25 days latter (n=149). The breeding season lasted 70 days for T5 and 100 days for treatments 1, 2, 3 and 4. The reproductive managements affected (P<0.05) the pregnancy rate per AI (T1= 73.7; T3= 67.2; T4= 47.2 and T5= 68.5%). The percentage of pregnant cows at the end of the breeding season was affected (P<0.05) by treatment and parity (92.3; 89.5; 82.7; 96.5 and 91.3%), respectively for the five treatments. Effect of treatments were observed (P<0.05) on interval between parturitions (400.6; 398.9; 393.6; 381.8 and 374.0 days) and days to calving (54.0; 50.0; 42.0; 23.0 and 21.0 days), respectively. Parity calf sex and strategies of reproductive management affected the body weight of the calve at weaning. Timed AI allows that more cows get pregnant at the beginning of the beeding season, reducing days to calving and interval between parturitions, reducing the breeding season period. Associated to timed AI, detection between days (17 to 25) after timed AI increased number of calves born to AI.
Mestre
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Crites, Benjamin R. "COMPARISON OF CONCEPTION RATES IN BEEF CATTLE INSEMINATED WITH EITHER SEXEDULTRA™ SEX-SORTED SEMEN OR CONVENTIONAL SEMEN IN FIXED-TIME ARTIFICIAL INSEMINATION (FTAI) PROTOCOLS." UKnowledge, 2017. https://uknowledge.uky.edu/animalsci_etds/80.

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Estrous synchronization and artificial insemination (ESAI) are reproductive technologies that cattlemen can use to improve the reproductive performance of their herds. Controlling the gender ratio of the calf-crop can also improve the opportunity for increased revenue and profit. Producers are able to shift and/or control the gender ratio of their calf crop by incorporating sex-sorted semen into their AI programs. However, decreased conception rates to AI have been previously observed when sex-sorted semen was used in comparison to conventional semen of the same sires. The objective of the first study was to determine if conception rates will differ in females inseminated with conventional semen or SexedULTRA™ sex-sorted semen when estrus is synchronized using an industry-standard, 7-d CO-Synch + Controlled Internal Drug Release (CIDR) protocol for fixed-time artificial insemination (FTAI). The objective of the second study was to determine if conception rate to FTAI differs between SexedULTRA™ sex-sorted and conventional semen when yearling beef heifers are synchronized using a 14-d controlled internal drug release (CIDR) - PGF2α (PGF) protocol modified to optimize the control of ovulation and timing of insemination.
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11

Figueiredo, Eliana Valéria Covolan 1965. "Avaliação de custos econômicos e energéticos de novas tecnologias de inseminação artificial na reprodução de bovinos de corte raça Nelore /." Botucatu, 2004. http://hdl.handle.net/11449/101711.

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Orientador : Flávio Abranches Pinheiro
Banca: Izabel Cristina Takitane
Banca: Ciro Moraes Barros
Banca: Geraldo Sant'Ana C. de Barros
Banca: Evaristo Marzabal Neves
Resumo: A bovinocultura de corte é de reconhecida importância no agronegócio brasileiro (mercado interno e externo), sendo que o país tem o segundo rebanho bovino mundial, com cerca de 80% destinados a produção de carne (maioria de zebuínos). Um dos limitantes desta atividade é a reprodução dos animais, que permite que o rebanho cresça em número e qualidade. Atuando-se sobre a reprodução, pode-se melhorar a conversão alimentar, diminuindo o custo. A inseminação artificial (IA) tem grande importância na obtenção de ganhos quantitativos e qualitativos (e.g. ganho genético), além de permitir um melhor controle do rebanho. Novas tecnologias de inseminação estão sendo aperfeiçoadas, inclusive tratamentos hormonais que possibilitam a IA com tempo fixo (IATF). Considerando a questão energética, é importante o desenvolvimento de tecnologias que otimizem os gastos energéticos na bovinocultura. Este trabalho tem por objetivo avaliar os custos econômicos (valores em reais, julho de 2003) nos manejos reprodutivos: IA convencional (IAC), IATF (GnRH-PGF2 -GnRH, GnRH-PGF2 -BE), GP (controle, GnRH-PGF2 e IA) e Monta; em vacas Nelore (zebuínos), além de fazer considerações sobre o gasto energético biológico destes manejos. A partir de dados obtidos em uma fazenda comercial da região de Botucatu, SP, foram realizadas análises de custos de reprodução de bezerros, nas tecnologias de IAC, IATF (grupos GPG-9, GPG-12, GPE-15 e GPE-18) e GP (GP-21 e GP-24) associados à Monta; e Monta-Simulado. O melhor Custo Total Unitário de reprodução por bezerro (CTU) foi observado na IAC (R$ 127,00) com taxa de prenhez (TxPr) de 84%. Na IATF, o melhor resultado foi do grupo GPE-15 (R$ 130,00, TxPr 74%)...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Beef cattle is a very important sector in Brazilian agribusiness, both in domestic and international market. Brazil has the second largest bovine herd in the world, with 80% of beef cattle (mostly Bos indicus). A limiting factor of this activity is the animal reproduction, which allows herd improvement and growth. Acting on reproduction may allow improvements on feed conversion, diminishing costs. Artificial insemination (AI) is a way of obtaining quantitative and qualitative gains (genetic improvement), in addition to a better herd management. New technologies on AI are been developed, including hormonal treatments which allow timed fixed AI (TAI). Besides, on the energetic approach, the development of new technologies optimizing energy expenses is also very important. The aim of this study was to evaluate the economic costs (in Reais, July 2003) on several reproductive handlings: Conventional AI (IAC), Timed AI (TAI; GnRH-PGF2 -GnRH; GnRH-PGF2 -BE), Synchronized estrus GP (control, GnRH-PGF2 and AI) and Natural Service; in Nelore cows (Bos indicus), in addition to making short considerations regarding energetic expenses on those handlings. Reproduction costs analysis were performed on data obtained on a commercial farm in Botucatu, SP, on IAC and TAI (groups GPG-9, GPG-12, GPE-15 and GPE-18) and GP (GP-21 e GP-24) associated to Natural Service; and simulated Natural Service group. The best total reproduction cost per calf (CTU, R$ 127,00) was observed in IAC with the pregnancy rate (TxPr) of 84%; otherwise, in TAI, the best result was from GPE-15 (R$ 130,00, TxPr 74%). The simulated Natural Service group had a CTU of R$ 116,00, with TxPr of 87%. The other groups obtained CTUs of R$163,00 (GPG-12, TxPr 69%), R$174,00 (GPE-18, TxPr 68%), R$181,00 (GP-21, TxPr 59%), R$ 189,00 (GPG-9, TxPr 67%) e R$ 338,00 (GP-24 TxPr 31%)...(Complete abstract click electronic access below)
Doutor
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12

Rocha, Dimas C. "Efeito da concentração do sêmen e horário de inseminação artificial a tempo fixo sobre a prenhez em fêmeas bovinas de corte." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2007. http://hdl.handle.net/10183/15613.

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Em experimento conduzido com o objetivo de avaliar os efeitos da concentração da dose de sêmen e o horário da inseminação artificial a tempo pré-fixado, foram utilizadas 516 fêmeas bovinas. Os animais, das raças Aberdeen Angus (Bos taurus) e Braford (Bos taurus 5/8 x Bos indicus 3/8) eram constituídos de 270 novilhas e 246 vacas multíparas. Os animais foram submetidos a um protocolo de sincronização de estros e ovulação através de implante vaginal contendo 250 mg de Acetato de Medroxiprogesterona (MAP) associado a duas aplicações de Benzoato de Estradiol (BE), sendo a primeira de 2 mg IM por ocasião da inserção do implante e a segunda de 1 mg IM vinte e quatro horas após a retirada do mesmo. Quando da remoção do implante foram administrados 500 mcg de Cloprostenol Sódico. As inseminações foram efetuadas às 48, 54 ou 60 horas após a retirada do implante, utilizando para cada momento duas concentrações distintas de espermatozóides viáveis, 10 e 20 milhões por dose. Verificou-se que as fêmeas (em especial as novilhas) inseminadas às 48 horas com 20 milhões de sptz/dose apresentaram índice de prenhez significativamente maior do que as inseminadas no mesmo momento com 10 milhões sptz/dose. As vacas inseminadas com 10 milhões de sptz às 60h apresentaram melhor taxa de prenhez (p<0,05) quando comparadas às inseminadas com 10 milhões de sptz às 48h. O percentual de prenhez encontrado nas vacas foi significativamente maior que o das novilhas, assim como o verificado nas fêmeas Aberdeen Angus, comparadas às Braford. A taxa de prenhez de novilhas inseminadas a tempo fixo pode ser incrementada utilizando-se maior número de espermatozóides viáveis por dose inseminante.
The objective of this study was to analyse the effects of semen concentration and moment of fixed timed insemination on pregnancy rates in 516 beef cattle females of the Aberdeen Angus (Bos taurus) and Braford (Bos taurus 5/8 x Bos indicus 3/8) breeds. The females were constituted of 270 heifers and 246 multiparous cows. The animals were all submitted to a synchronization program consisting of vaginal implants of 250mg of medroxiprogesterone acetate (MPA) associated to application of 2mg IM of estradiol benzoate (EB).After 7 days the implants were removed and 500 mg of cloprostenol were injected at the time. After 24hs of implant removal 1mg IM of EB was injected. The inseminations were done 48, 54 and 60 hours after the removal of the implants and semen with 10 and 20 million viable spermatozoa per dosis was used. The females (specially the heifers) of the group inseminated 48 hours after implant removal and using semen with 20 million viable sptz showed a significant higher percentage of pregnancy than the inseminated 48 hours using 10 million viable sptz. The cows inseminated at 60 hours with 10 million sptz showed higher pregnancy rates (p<0,05) than cows inseminated at 48 hours with 10 million sptz. The total pregnancy rate achieved on the cows was significantly higher than on the heifers. The females of the A. Angus group had higher pregnancy rates than the females of the Braford breed. The pregnancy rate of heifers fixed-timed inseminated can be increased using a higher semen concentration.
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Pereira, Jhonata Vieira Tavares do Nascimento. "Variáveis morfométrica e hormonais ovariana e sanguínea de vacas Nelore submetidas a diferentes protocolos de IATF." Universidade Federal de Viçosa, 2014. http://locus.ufv.br/handle/123456789/5184.

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This study was aimed to investigate the effects that different protocols for induction and synchronization of estrus and ovulation, with the use of eCG, BE, CE or GnRH associated with progestin could have on the follicle growth and pre-ovulatory follicle diameter. Furthermore the relationship with progesterone, LH, insulin, cortisol in the follicular fluid concentration and progesterone, cortisol, insulin serum concentrations of cows submitted to protocols. Ninety Nelore suckled cows were divided into six groups, 15 cows per protocol. The protocols consisted in the placement and removal of an intravaginal progesterone device (IPD) (0.75g of progesterone) in the first and eighth day respectively; application of prostaglandin (PGF2 ) on the eighth day, and except in protocol 1 was used estradiol benzoate (EB) on day 1. The other differences in the delineation of protocols were: Protocol 1 day 1 and day 8 (GnRH); Protocol 2 day 6 (PGF2 ), day 8 (PGF2  + estradiol cypionate (EC)); Protocol 3 day 8 (eCG + EC); Protocol 4 day 8 (eCG + EB); Protocol 5 day 8 (eCG), day 9 (EB); Protocol 6 day 9 (EB). Overall 93.3% (84/90) of cows responded to synchronization protocol. However, it was observed that 28.9% of cows (26/90) did not have a synchronization of a new follicular wave, checked by the number of cows which have not developed a dominant follicle (5/26), cows with early ovulation (15/26) and cows that had a dominant follicle in regression process (6/26). There was no statistical difference in growth and diameter of the pre-ovulatory follicle between protocols. Progesterona, LH, insulina, cortisol concentrations on follicular fluid, as well as in cortisol and insulin serum concentration did nor differ with the protocols used. Although, in protocol 2, lower progesterone concentrations (P<0.05) were observed in the withdrawal of IPD. Twenty seven oocytes were recovered, which were classified according to quality: 1 (n=12), 2 (n=6), 3 (n=7) e 4 (n=2). The antecipation in the prostaglandin application in two days from IPD withdrawal result in lower progesterone concentrations.
O objetivo desse estudo foi verificar os efeitos que diferentes protocolos de indução e sincronização do estro e da ovulação, com utilização de eCG, BE, CE ou GnRH associados a um progestágeno, podem ter sobre o crescimento e diâmetro do folículo pré-ovulatório, e suas relações com a concentração, no fluido folicular, de progesterona, LH, insulina e cortisol, e com a concentração sérica de progesterona, cortisol e insulina das vacas submetidas aos protocolos. Foram utilizadas 90 vacas Nelore solteiras, com mais de nove meses pós-parto, divididas em seis protocolos, sendo 15 vacas por protocolo. Todos os protocolos consistiam na colocação e retirada de um dispositivo intravaginal de progesterona (DIP) (0,75 gramas de progesterona) no primeiro e no oitavo dia, respectivamente; aplicação de prostaglandina (PGF2) no oitavo dia; e exceto no protocolo 1, foi utilizado benzoato de estradiol (BE) no dia 1. As outras diferenças no esquema dos protocolos foram: protocolo 1 dia 1 e dia 8 (GnRH); protocolo 2 Dia 6 (PGF2), dia 8 (PGF2cipionato de estradiol (CE)); protocolo 3 dia 8 (eCG + CE); protocolo 4 dia 8 (eCG + BE); protocolo 5 dia 8 (eCG), dia 9 (BE); protocolo 6 dia 9 (BE). Em geral, 93,3 % (84/90) de vacas responderam ao protocolo de sincronização. Entretanto, foi observado que 28,9 % das vacas (26/90) não apresentaram sincronização eficiente de uma nova onda folicular, constatado pelo número de vacas que não desenvolveram folículo dominante (5/26), as vacas que ovularam precocemente (15/26), e as vacas que tiveram um folículo dominante que estava em processo de regressão (6/26). Não houve diferença estatística no crescimento e diâmetro do folículo pré-ovulatório entre os protocolos. Não houve efeito, entre os protocolos, na concentração no fluido folicular de progesterona, LH, insulina, cortisol, bem como na concentração sérica de cortisol e insulina. Contudo, no protocolo 2, foi verificada menor concentração sérica (P < 0,05) de progesterona na retirada do DIP. Foram recuperados 27 ovócitos, que foram classificados de acordo com a qualidade em 1 (n=12), 2 (n=6), 3 (n=7) e 4 (n=2). A antecipação na aplicação de vprostaglandina, em dois dias da retirada do DIP, resulta em menor concentração de progesterona circulante.
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14

Branco, Rui Afonso d'Orey. "Análise do impacto da introdução da técnica de inseminação artificial a tempo fixo e "touro de varrimento" em vacas de raça alentejana na performance produtiva e económica." Master's thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2014. http://hdl.handle.net/10400.5/6882.

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Dissertação de Mestrado Integrado em Medicina Veterinária
Portugal é um pais deficitário na produção de carne bovina, sendo que nos últimos anos o consumo de carne em Portugal tem sido duas vezes superior ao produzido obrigando à importação de cerca de 357M€ por ano. Em contrapartida as exportações não chegam aos 7% do produzido, o que cria uma balança comercial altamente deficitária. Mediante deste panorama é necessário produzir mais e melhor. Com esse propósito foi realizado um estudo que tem como objectivo perceber se a introdução da inseminação artificial a tempo fixo (IATF) numa vacada dc apetência cárnea, pode ou não, melhorar a performance produtiva e económica. Para o estudo foram avaliadas 250 vacas aleitantes da Raça Alentejana das quais 181 foram dadas como aptas para iniciar o protocolo de sincronização de cio. O histórico dos últimos quatro anos destes animais apresenta uma taxa de fertilidade média de 60%. Os animais iniciaram então um protocolo de sincronização em que no dia 0 foi feito um exame ginecológico e administrado GnRH e introduzido um implante de progesterona. No dia 7 o implante foi retirado e administrado eCG e PGF2α e passadas 52 horas foi realizada a IA e nova administração de GnRH. Passado 15 dias as vacas foram colocadas com um touro de varrimento. Os resultados demostram uma taxa de gestação média de 75% após apenas dois cios, o cio referente à sincronização e o cio seguinte. A diferença de fertilidade de 15%, ao qual se junta os animais refugados por deficiências reprodutivas, criou em termos de benefício liquid, no conjunto das seis explorações, de 9204,50€.
ABSTRACT - Portugal is a country deficient in beef production. In recent years, meat consumption in Portugal has been twice its production, forcing the import of around € 357 million every year. However, exports are not reaching 7 % of what is produced, which creates a highly unfavorable trade balance. Four this purpose a study aims to understand if the introduction of oestrus synchronization and a fixed time artificial insemination can increase the herd productive and global economic performance. For the study we enrolled 250 beef cows (Alentejana breed) of which only 181 were approved to start the oestrus synchronization protocol. The history of these cows for the last four years showed a fertility rate of 60 %. Synchronization protocol started on day 0, with a gynecological examination, a GnRH administration and the insertion of the progesterone implant. On day 7 the implant was removed and eCG and PGF2 were administered. After 52 hours AI was performed and a new GnRH injection was given. After 15 days, the cows were placed with a clean-up scanning bull. The results show that 75% of these 181 cows became pregnant after just two heats. Economically this difference of 15% in fertility, to which we added the animals culled for reproductive diseases, resulted in a economic benefice in the 6 farms of € 9,204.50
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Raimundo, Inês da Silva. "O efeito de alguns factores na eficiência da inseminação artificial em tempo fixo em bovinos de carne." Master's thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2014. http://hdl.handle.net/10400.5/7880.

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Dissertação de Mestrado Integrado em Medicina Veterinária
A partir de 385 IATF realizadas em fêmeas bovinas de carne foram estudados os efeitos de diversos factores: tipo de inseminação artificial (IA), técnico de inseminação, intervalo entre a descongelação da palhinha de sémen e a deposição da dose no aparelho reprodutor da vaca, factores ambientais, número de partos e idade das vacas, intervalo parto-IA e raça na eficiência da técnica, medida objectivamente através da taxa de gestação. Todas as fêmeas foram sujeitas a um protocolo de sincronização de ovulação do tipo CO-Synch modificado, com recurso a um dispositivo intravaginal de libertação controlada de fármaco (CIDR) e gonadotrofina coriónica equina (eCG). A taxa de gestação foi calculada com base no diagnóstico de gestação, realizado através de ecografia cerca de 30 dias após a IA. Verificou-se que o tipo de IA (intracornual profunda, à entrada do corpo do útero ou cervical) não influenciou a taxa de gestação (p≥0,05), tal como o número de partos e idade da fêmea, intervalo parto-IA e a raça (p≥0,05). Os factores ambientais temperatura mínima, média e máxima, humidade relativa, velocidade do vento e precipitação também não exerceram influência na taxa de gestação (p≥0,05), tal como o índice temperatura-humidade (ITH), que relaciona temperatura e humidade relativa. Ao contrário de outros estudos, ITH>74 não foi responsável por quebras nas taxas de gestação (p≥0,05). Não foi possível estabelecer relação entre o técnico de inseminação e a eficiência da IATF em bovinos de carne (p≥0,05). Os factores intervalo descongelação-IA e traumatismo associado à IA influenciaram a taxa de gestação (p˂0,05). Concluiu-se que quanto maior o intervalo descongelação-IA, menor a probabilidade da fêmea bovina ficar gestante. Também a ocorrência de traumatismo diminuiu as hipóteses das vacas ficarem gestantes. Adicionalmente, registou-se evidência de relação entre estes dois factores.
ABSTRACT - THE EFFECT OF SOME FACTORS ON EFFICIENCY OF FIXED-TIME ARTIFICIAL INSEMINATION (FTAI) IN BEEF CATTLE - From 385 FTAI carried out on beef females some factors were studied like the type of artificial insemination (AI), insemination technician, interval between the thawig and the deposition of the semen on the reproductive tract of the cow (thawig-AI interval), environmental factors, parity and age of cows, calving-AI interval and breed, which may influence the fertility, measured objectively through the pregnancy rate. All bovine femals were synchronized for ovulation through a CO-Synch modified protocol, adding an intravaginal device controlled drug release (CIDR) and equine chorionic gonadotropin (eCG). The pregnancy rate was calculated on the basis of the pregnancy diagnosis, carried out through ultrasound approximately 30 days after AI. There was no difference (p≥0,05) between deep cornual inseminantion, conventional insemination (semen deposition into the uterine body) and cervical deposition. The cow age or parity, interval between calving and AI and the breed also did not influence the pregnancy rate (p≥0,05). Environmental factors like average, maximum and minimum daily temperatures, relative humidity, wind speed and precipitation also did not exert influence on the rate of pregnancy (p ≥ 0.05), as the temperature-humidity index (THI), which relates temperature and relative humidity. Unlike other studies, ITH > 74 was not responsible for decrease on the pregnancy rates (p ≥ 0.05). It had not been possible to establish if there was any relationship between the insemination technician and the efficiency of FTAI in beef cattle. The thawig-IA interval and trauma associated to AI influenced the pregnangy rate (p˂0,05). It was concluded that the higher the thawing-IA interval , the lower probability of the cow becoming pregnant. Also the occurrence of traumatic injuries didn’t favor the chances of bovine females becaming pregnant. In addition, we have found evidence of correlation between these two factors.
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Gaievski, Francisco Romano. "Sincronização do estro e da ovulação após prévio uso de progesterona intravaginal e gonadotrofina coriônica equina em bovinos de corte visando à inseminação artificial em tempo fixo = Timing and ovulation estro after prior use of progesterone intravaginal and equine chorionic gonadotropin (eCG) in beef cattle aiming to fixed-time artificial insemination / Francisco Romano Gaievski ; orientador, Luiz H. Kozicki." reponame:Biblioteca Digital de Teses e Dissertações da PUC_PR, 2012. http://www.biblioteca.pucpr.br/tede/tde_busca/arquivo.php?codArquivo=2368.

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Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2012
Bibliografia: f.26-30
A diversidade e grandiosidade da pecuária Brasileira revelam enormes contrastes e particularidades, seja nas tecnologias adotadas, nos rebanhos existentes, na topografia, na mão de obra e no clima, que ocorrem em um país com dimensões continentais. Dentre
The diversity and grandiosity of Brazilian?s livestock, reveals giants contrasts and particularities, at adopted technology, existing herds, topography, labor force and weather that occur in a country with continental dimensions. Among the production fact
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17

Hill, Scott L. "Serum and plasma metabolites and insemination timing associated with greater pregnancy risk in suckled beef cows subjected to artificial insemination programs." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/34458.

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Doctor of Philosophy
Department of Animal Sciences and Industry
Jeffrey S. Stevenson
Four experiments were conducted in beef cows to determine factors that increased the probability of pregnancy per AI when cows are inseminated by appointment. Cows in all experiments were inseminated after a 7-d CO-Synch + CIDR program (100 μg GnRH [2 mL Factrel, Pfizer Animal Health, Whitehouse Station, NJ] 7 d before 25 mg PGF₂[subscript]α [d 0; 5 mL Lutalyse; Pfizer Animal Health]). Experiment 1 compared 1 vs. 2 inseminations and GnRH injection times at 60 and 75 h after the CO-Synch + CIDR program. Delaying AI until 75 h, according to interpretation of estrus-detection patches, for cows not in estrus by 60 h after CIDR insert removal increased (P < 0.05) pregnancy risk (PR) compared with cows not in estrus and inseminated at 60 h (51.4 vs. 41.7%), respectively. The necessity of GnRH injection concurrent with AI was tested in experiment 2. Cows displaying estrus by 65 h that were injected with GnRH had similar PR to cows in estrus and not treated with GnRH (61.9 vs. 60.4%), respectively. Cows in experiment 2 that did not display estrus, but were treated with a GnRH injection at 65 h and then inseminated at 84 h after CIDR insert removal had increased PR compared with similar cows not treated with GnRH (33.4 vs. 15.0%; P < 0.01), respectively. Experiments 3 and 4 were observational studies conducted to determine if blood metabolites glucose and beta-hydroxy butyrate (BHB experiment 3), or physical body and blood metabolites, (glucose, BHB, non-esterified fatty acids [NEFA], blood urea nitrogen [BUN], body weight, rump fat [RF], or BCS; experiment 4) were indicative of future reproductive success in suckled beef cows enrolled in a timed AI program. In experiment 3, plasma glucose concentration 10 d before AI was lesser (P = 0.01; 52.2 vs. 56.9 mg/dL) and serum BHB concentration was lesser (P < 0.01) in cows that became pregnant 35 d after timed AI than for cows that did not become pregnant (600 vs. 690 μM), respectively. Experiment 4 identified relationships between indicators and reproductive success including the finding that serum NEFA concentration 2 to 4 wk before AI is negatively correlated (P < 0.05) with PR to AI.
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Al-Furaiji, Mansour M. A. "The use of a monoclonal antibody to pregnant mare serum gonadotrophin in superovulation of cattle." Thesis, University of Aberdeen, 1989. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602258.

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Embryo transfer plays a very important role in the cattle industry and its application requires a consistent supply of viable embryos for use in such programmes. One way of achieving this is the development of reliable superovulation regimens, yielding a large number of high quality embryos. Superovulation with pregnant mare serum gonadotrophin (PMSG) induces a second wave of follicles after ovulation because it is eliminated slowly from the peripheral blood, causing high concentrations of oestradiol. This oestradiol may have an adverse effect on fertilization and early embryonic development. Administering PMSG antiserum after ovulation may improve the quality by neutralizing PMSG activity. The object of this study was to examine the role of monoclonal anti- PMSG (Neutra-PMSG; Intervet UK) in a superovulatory regime for cattle based on PMSG with the objective of increasing the number of viable embryos produced. Two experiments were conducted in this study. In experiment 1, cows were superovulated with 2500 iu of PMSG (Folligon; Intervet UK) im on day 101 of their oestrous cycle, whereas in experiment 2, heifers were superovulated with 1000, 2000, 3000 or 4000 iu of PMSG (PMSG1, 2, 3 or 4, respectively) im on day 10 1 of their oestrous cycle. In experiments 1 and 2, animals were given 2 ml of PG (PG3) im 48 h after PMSG injection and oestrus was observed in the same manner as described above. When data were evaluated in respect of the PMSG/APMSG dose level, there were no significant differences (P>0.05) in the numbers of CL and usable number of embryos between APMSG treatment and the appropriate control. Treatment with APMSG in the 3000 iu PMSG dose group reduced (P 0.05) the numbers of LF compared to control (1.3 v 5.5). When data were analysed based on the dose levels of PMSG, the total number of ova/embryos and the number of usable embryos were higher in heifers which received 2000 iu of PMSG compared to those which received 1000, 3000 or 4000 iu (7.1 v 2.1, 6.6 or 5.6 and 6.3 v 2.1, 4.8 or 3.2, respectively) . In conclusion the results indicate that PMSG dose 2000 iu is the favoured dose for superovulating heifers. The administration of Neutra-PMSG 36, 48, 60, 72, 84 or 96 h after PG3 injection, despite reducing LF numbers and preventing the rise in 0E2 after ovulation, had no significant effect on the number of usable embryos recovered.
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Dorsey, Benjamin Reese. "Effect of Timing of Insemination and Synchronization of Estrus Method on Artificial Insemination (AI) Pregnancy Rates in Beef Heifers." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/42873.

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Objectives were to evaluate time of insemination relative to estrus and synchronization with melengestrol acetate (MGA) plus prostaglandin (PG) or progesterone insert (CIDR) plus PG on AI pregnancy rate in beef heifers (n = 662) during Fall or Spring. Fall heifers (n = 349) received MGA-PG (MGA for 14 d followed by PG on d 18) or CIDR-PG (CIDR for 7 d, PG administered 1 d before CIDR removal). Estrus was monitored by HeatWatch® (n = 200) or visually (n = 149). Spring heifers (n = 313) underwent CIDR-PG with detection of estrus by HeatWatch®. Heifers not in estrus by 96-100 h after PG were bred AI as non-responsive AI (NRAI). Across seasons, 548 heifers were bred following estrus (EAI). Heifers synchronized during the Fall with MGA received more (P < 0.05) mounts than Fall CIDR heifers (76.8 ± 6.7 and 47.6 ± 7.4, respectively), but duration of estrus was similar. Fall CIDR heifers had greater (P < 0.05) mounting activity and duration of estrus (47.9 ± 5.2 mounts and 15.5 ± 1.1 h) compared to Spring CIDR heifers (34.5 ± 3.1 mounts and 12.7 ± 0.6 h). Heifers grouped in 4 h blocks from 0 to 24 h had no difference (P > 0.05) in pregnancy rates (mean 62.5 %). Treatment had no effect (P > 0.05) on EAI pregnancy rates. Pregnancy rates across seasons for EAI, NRAI and overall was 61.0 %, 26.3 %, and 54.5%. In conclusion, a 24 h window may exist to successfully AI heifers.
Master of Science
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Nadir, Sher. "Effect of high and low dosage of fresh and frozen semen on accessory sperm number, fertility and embryo quality in artificially inseminated cattle." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-10222009-125208/.

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Alexander, Dayna C. "Effect of delaying insemination in beef heifers not expressing estrus by 48 hours after a 7-d CO-Synch plus controlled internal drug release timed artificial insemination protocol." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/34522.

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Master of Science
Department of Animal Sciences and Industry
Karol E. Fike
David M. Grieger
Synchronizing estrus before AI is an effective way to shorten the breeding season, and increasing the number of pregnancies per AI may lead to greater use and acceptance of synchronization protocols among beef producers. Our objective was to determine if pregnancy rates to fixed-time AI (FTAI) would be improved by delaying insemination in heifers not expressing estrus before FTAI in a 7-d CO-Synch + controlled internal drug release (CIDR) estrus-synchronization protocol. In Experiment 1, yearling beef heifers (n = 465) at three locations of commercial and purebred herds were treated with GnRH (Cystorelin 100 µg im) and a CIDR insert (1.38 g of progesterone) on Day 0. On Day 7 CIDR inserts were removed and all heifers received PGF[subscript]2α (Lutalyse 25 mg im) and were fitted with an estrus-detection patch (Estrotect; Rockway, Inc.). Heifers were assigned to three treatments based on estrus-detection patch color at 48 h after PGF[subscript]2α: (1). Estrus-Red 48 h (Red 48; n = 180), heifers that expressed estrus and were inseminated at 48 h; (2). Non-Estrus-Gray 48 h (Gray 48; n = 137) heifers that did not express estrus and were inseminated at 48 h; and (3). Non-Estrus Delayed- 56 h (Gray 56; n = 148), heifers that did not express estrus at 48 h, and were not inseminated until 56 h after PGF[subscript]2α. Pregnancy rate to AI was greatest (P < 0.0001) for Red 48 heifers (67.8%) compared with heifers in the Gray 48 (39.4%) and Gray 56 (42.6%) treatments. Heifers assigned to Gray 48 and Gray 56 achieved similar (P = 0.83) pregnancy rates. In Experiment 2, yearling beef heifers (n = 257) at two different locations were treated with the same 7-d CO-Synch protocol, but heifers were assigned to three different treatments based on estrus-detection patch color at 48 h after PGF[subscript]2α: (1). Estrus-Red 48 h (Red 48; n =95), heifers that expressed estrus and were inseminated at 48 h; (2). Non-Estrus-Gray 48 h (Gray 48; n = 84), heifers that did not express estrus but were inseminated at 48 h; and (3). Non-Estrus Delayed- 72 h (Gray 72; n = 78), heifers that did not express estrus at 48 h, and were not inseminated until 72 h after PGF[subscript]2α. Pregnancy rate to AI was greatest (P = 0.004) for Red 48 heifers (62.1%) compared with heifers in Gray 48 (40.5%), and Gray 72 (46.2%). No difference in pregnancy rates (P = 0.75) was detected between heifers assigned to treatments Gray 48 and Gray 72. Delaying insemination in heifers not expressing estrus by 48 h after PGF[subscript]2α did not improve pregnancy rates to AI.
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Samuelson, David J. "Accuracy of predicting genetic merit of A.I. sampled bulls from pedigree information and the impact of son's proof on dam's PTA." Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09292009-020134/.

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23

DeJarnette, James Melton. "The effects of sperm dose, semen quality, and retrograde sperm blockage on accessory sperm number and embryo quality in the artificially inseminated bovine." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/41929.

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Grove, Mary Beth. "Optimal time of insemination in dairy cattle identified in estrus by HeatWatch." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08292008-063759/.

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Dalton, Joseph C. "Factors Important to the Efficiency of Artificial Insemination in Single-Ovulating and Superovulated Cattle." Diss., Virginia Tech, 1999. http://hdl.handle.net/10919/27139.

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To identify factors important to the efficiency of artificial insemination in cattle, four studies were conducted. In the first study, the addition of cream to the inseminate was used in an attempt to increase accessory sperm number. On d 6 after insemination, 60 embryos were evaluated. The addition of cream to the inseminate had no effect on accessory sperm number. In the second study, cryopreserved semen of a marked bull (spermatozoa exhibiting a semi-flattened anterior head) was matched with semen from an unmarked bull (conventional sperm head shape) to determine competitively the effect of a deep uterine insemination on accessory sperm number. Forty embryos were recovered 6 d after insemination and the ratio of accessory sperm observed was different: 62:38 for unmarked semen in the uterine body and marked semen in the uterine horn, and 72:28 for unmarked semen in the uterine horn and marked semen in the uterine body (P < .05). In the third study, superovulated cows were utilized to determine the effect of artificial insemination time on fertilization status and accessory sperm number. Cows were inseminated once at 0 h (n=10), 12 h (n=10), or 24 h (n=10) after the first standing event. On d 6 after insemination, 529 embryos(ova) were recovered. Fertilization rates were 29% (0 h); 60% (12 h); and 81% (24 h)(P < .01). Percentages of embryos with accessory sperm were: 5 (0 h); 8 (12 h); and 41(24 h) (P < .01). In the fourth study, three experiments utilizing superovulated cows were conducted to provide a basis for distinguishing unfertilized ova from very early embryonic death. In Exp. 1, recovered d 6 unfertilized ova were classified morphologically as either: 1) typical, 2) satellite, or 3) fragmented. In Exp. 2, recovered d 6 unfertilized ova from the third study were classified morphologically, and typical ova were fixed. In Exp. 3, ultrastructural features of preovulatory, tubal-stage, and typical d 6 unfertilized ova were investigated. Preovulatory ova revealed normal ultrastructure; tubal-stage ova exhibited evidence of degeneration; typical d 6 ova were degenerated and contained no discernable organelles. The first three studies support the use of accessory sperm evaluation as an alternative measure of fertility. The final study provides a basis from which future embryologists may distinguish fertilization failure from very early embryonic death.
Ph. D.
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26

Karabinus, David Scott. "The effects of the cervix on the transport of morphologically abnormal spermatozoa in the female bovine." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/54335.

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Two studies were conducted to investigate the role of the bovine cervix in filtering abnormal sperm. ln Study 1, semen containing high levels of abnormal sperm was vaginally deposited in 12 cows 80 hours after prostaglandin F₂α treatment. At slaughter, 4-, 8- or 12 hours post-insemination, sperm were flushed from the excised uteri with fixative. Pooled across times post-insemination, viability was greater for uterine vs inseminate sperm, based upon vital smears prepared from inseminate and uterine flush samples. Uterine levels of normal sperm, determined by differential interference contrast (DIC) microscopy, were greater than were inseminated. In Study 2, heifers were estrus synchronized in pairs using prostaglandin F₂α, then inseminated with semen containing high levels of abnormal sperm. In each pair, semen of high viability (Experiment 1, n=10) or low viability (Experiment 2, n=6) was deposited vaginally in one heifer and within the uterine corpus of the other. Using DIC microscopy, viability and morphology were coincidentally determined for sperm in samples from the fixed inseminate and the retrograde mucus, vaginal mucus, cervix, uterus and in vitro incubation of inseminate recovered and fixed 12 hours post-insemination. Uterine sperm quality did not differ between insemination sites, except lower uterine levels of live abnormal sperm alter intrauterine vs vaginal insemination of low viability semen probably due to disproportionately low viability of one abnormality. Sperm viability was enhanced and morphology unchanged in the uterus vs low viability inseminate, while sperm viability was unchanged and abnormal sperm subtly reduced in uterus vs high viability inseminate. Greater levels of live and live normal sperm were found deeper between cervical folds than at apical aspects of folds. Vaginal mucus sperm viability was lower compared to other tract locations and inseminate, especially after high viability insemination. Compared to inseminate viability, retrograde mucus sperm viability was high after vaginal insemination and low alter intrauterine insemination. Differential death of abnormal vs normal sperm neither with incubation of insemination in vitro nor, presumably, in vivo. Results show little evidence of cervical filtration based upon sperm morphology. Sperm retention in the female tract was predominantly related to sperm viability with only very subtle morphology effects.
Ph. D.
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27

Peres, Kenya Costa [UNESP]. "Transporte placentário via cavéola na placenta de bovinos clonados e transgênicos." Universidade Estadual Paulista (UNESP), 2014. http://hdl.handle.net/11449/115903.

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A utilização da transgenia com a proteína fluorescente verde (GFP) como marcador de células de origem fetal nas placentas de clones bovinos servirá de modelo inédito para estudo morfofisiológico e imunológico da interação materno-fetal, visto que possibilitará o seu mapeamento, diferenciando as células fetais das maternas. Tal modelo terá aplicação direta, principalmente porque estes são animais que apresentam problemas em relação ao seu desenvolvimento. Com o auxílio deste modelo, pretende- se verificar o transporte de substâncias entre a mãe e o feto via endocitose, pela imunolocalização das proteínas chamadas de caveolinas. Para tanto foram utilizados 06 bovinos clonados e 30 bovinos de inseminação artificial (IA) com idade até 90 dias de gestação, os quais tiveram seu desenvolvimento interrompido mediante abate humanitário das receptoras e ovariosalpingohisterectomia, com posterior recuperação do útero gestante. Foram coletados os placentônios e o cório. Uma parte das amostras foi recortada e fixada, por imersão, em solução de parafolmaldeído a 4% ou formoldeído a 10% em tampão fosfato de sódio (PBS) a 0,1M pH 7.4, solução de Zamboni (4% de paraformoldeído, 15% de ácido pícrico, em tampão fosfato de sódio a 0,1M pH 7.4), metacarn (60% de metanol, 30% de clorofórmio, e 10% de ácido acético glacial), para verificação da morfologia e realização de imuno-histoquímica para as proteínas caveolinas -1 e -2 (CAV -1 e CAV-2). As caveolinas -1 foram localizadas nos vilos fetais e maternos, mas sua marcação mais forte foi observada no estroma endometrial. As caveolinas -2 tiveram marcação positiva no trofoblasto e membrana corioalantoide, e, especificamente em célula trofoblástica gigante binucleada. Sendo assim, os resultados mostram que a proteína CAV-1 teve uma maior expressão em relação a proteína CAV-2 e que as proteínas CAV-1 e -2 são parte da composição das cavéolas, sendo .
The transgenic application of green fluorecent protein (GFP) as fetal cell marker on cattle cloned placenta could provide an exclusive model for studying the morphologic and immunologic maternal-fetal interactions, providing information about its mapping, distinguishing the fetal from maternal cells. This model will have direct application, mainly because these are animals that present problems during its development. With this model's support, we intend to verify the substances transport between mother and fetus during endocytocis, through the immunolocalization of protein named caveolae. For these, we used 06 cloned bovine and 30 cattle samples of artificial insemination (AI) with 90 days of pregnancy, which had been their development interrupted by humanitarian slaughter of the recipient and recovery of the pregnant uterus. We collected the placentome and the chorion. A part of the samples will be cutted and fixed, by immersion, on a solution containing 4% of parafomaldehyde or 10% of formaldehyde on a sodium phosphate buffer (PBS) at 0,1M pH 7.4, Zamboni solution (4% of paraformaldehyde, 15% of picric acid, on sodium phosphate buffer 0,1M pH 7.4), metacarn (60% of metanol, 30% of chloroform, and 10% glacial acetic acid), for morphologic and immunohistochemistry verification for caveolinas proteins -1 and -2 ( -1 CAV and CAV- 2). The caveolinas -1 were found in fetal and maternal villi , but its strongest staining was observed in the endometrial stroma . The caveolinas -2 had positive staining in trophoblast and chorioallantoic membrane , and specifically in giant trophoblastic binucleated cell . therefore the results were compared between cloned cattle and from AI or natural mating, for assisting on detection of the reason of many placental alterations, embryonic losses, spontaneous abortion, post-natal mortality and large offspring syndrome on laboratory-manipulated animals. The result suggests that the proteins caveolins -1 and ...
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28

Albuquerque, João Pedro de [UNESP]. "Estratégias para aumento da concentração de progesterona durante o desenvolvimento do folículo ovulatório em vacas holandesas em lactação submetidas à inseminação artificial em tempo fixo." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/136114.

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O presente estudo avaliou se a concentração de P4 durante o desenvolvimento do folículo ovulatório em protocolo a base de P4/BE e com uma aplicação de GnRH em seu início interfere na prenhez à IATF em vacas Holandesas em lactação. A hipótese é que vacas com maior P4 no dia da aplicação da 1ª dose de PGF2α terão maior fertilidade. Para alterar a P4 os animais (n=594) foram distribuídos aleatoriamente em dois grupos para receberem um ou dois dispositivos intravaginais de P4 (CIDR®, Zoetis, SP, Brasil). O protocolo utilizado foi: no d-11 inserção de 1 CIDR (novo ou previamente usado por 9 dias) + aplicação de 2mg i.m. de BE (Gonadiol®, Zoetis, SP, Brasil) + 100mcg i.m. de GnRH (Cystorelin®, Merial, SP, Brasil); d-4, aplicação de 25mg i.m. de Dinoprost (Lutalyse®, Zoetis, SP, Brasil); d-2, aplicação de 25mg i.m. de Dinoprost + 1mg i.m. de ECP (ECP®, Zoetis, SP, Brasil) + retirada do dispositivo de P4; d0, IATF. Os animais do grupo 2CIDR receberam um CIDR adicional no d-11, o qual foi retirado no d-4. Nos d-11 (n= 117), d-4 (n= 351), d0 (n= 214) e d10 (n= 72) foram colhidas amostras de sangue para determinação da concentração de P4. A P/IA foi determinada através de US nos d32 (DG1) e d60 (DG2). Dados binários foram analisados pelo PROC GLIMMIX, e os dados contínuos pelo PROC MIXED do SAS (foi considerada diferença significativa se P<0,05 e tendência se P<0,1). A P4 não diferiu entre os tratamentos no d-11 (1CIDR= 4,2±0,4 ng/ml; 2CIDR= 4,5± 0,4ng/ml; P>0,1), e no d-4 (1CIDR= 3,5±0,2ng/ml; 2CIDR= 3,8±0,2 ng/ml; P>0,1), porém foi detectada interação entre tratamento e presença de CL no início do protocolo na P4 no d-4 (sem presença de CL e 1CIDR= 2,7±0,3ng/ml; 2CIDR= 3,6±0,3ng/ml, com presença de CL e 1CIDR= 4,3±0,3ng/ml; 2CIDR= 4,0±0,3ng/ml; P<0,05). Não houve diferença na prenhez a IATF e nas perdas gestacionais entre os tratamentos [DG1: 1CIDR= 20,0 ...
The present study evaluated if P4 concentration during ovulatory follicle development in a timed artificial insemination (TAI) protocol based on P4/E2 affects pregnancy per AI in lactating Holstein cows. Our hypothesis is that cows that present higher P4 concentration at PGF2α administration have also higher fertility. To alter P4, animals (n=594) were randomly assigned to receive one or two intravaginals devices of P4 (CIDR®, Zoetis, SP, Brazil). TAI protocol utilized was: d-11 intravaginal device of P4 (new or previously used by 9 days) + 2mg im EB (Gonadiol®, Zoetis, SP, Brazil) + 100mcg im GnRH (Cystorelin®, Merial, SP, Brazil); d-4, 25mg im Dinoprost (Lutalyse®, Zoetis, SP, Brazil); d-2, 25mg im Dinoprost + 1mg im ECP (ECP®, Zoetis, SP, Brazil) + CIDR removal; d0, TAI. Animals in the group 2CIDR received an adicional CIDR at d-11, which was removed at d-4. At d-11 (n=117), d-4 (n=351), d0 (n=214) and d10 (n=72), blood samples were taken from cows for P4 concentration measurements. Pregnancy per AI was determined by ultrasound at d32 (DG1) and d60 (DG2). The binomial data were analyzed using PROC GLIMMIX and continuous data using PROC MIXED of SAS. An effect was considered significant when P<0.05 and tendency when P<0.1. P4 did not differ among treatments at d-11 (1CIDR=4.2±0.4ng/ml; 2CIDR=4.5±0.4ng/ml; P>0.1), and at d-4 (1CIDR=3.5±0.2ng/ml; 2CIDR=3.8±0.2 ng/ml; P>0.1). An interaction was detected between treatment and CL presence at the beginning of TAI protocol in P4 at d-4 (without CL and 1CIDR=2.7±0.3ng/ml; 2CIDR= 3.6±0.3ng/ml, with CL and 1CIDR=4.3±0.3ng/ml; 2CIDR= 4.0±0.3ng/ml; P<0.05). There was no difference among treatments in pregnancy per AI and pregnancy loss between DG1 and DG2 [DG1: 1CIDR= 20,0% (81/310) vs. 2CIDR= 15,7% (65/284); DG2: 1CIDR= 18,2% (74/310) vs. 2CIDR= 13,8% (57/283); Pregnancy loss: 1CIDR= 14,1% (7/81) vs. 2CIDR= 11,5% (7/64); P>0,1]. 37,0% (28/63)...
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29

Peres, Kenya Costa. "Transporte placentário via cavéola na placenta de bovinos clonados e transgênicos/." Dracena, 2014. http://hdl.handle.net/11449/115903.

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Abstract:
Orientador: Flavia Thomaz Verechia Pereira
Banca: Cristiana Andrighetto
Banca: Vanessa Gomes Ueno
Resumo: A utilização da transgenia com a proteína fluorescente verde (GFP) como marcador de células de origem fetal nas placentas de clones bovinos servirá de modelo inédito para estudo morfofisiológico e imunológico da interação materno-fetal, visto que possibilitará o seu mapeamento, diferenciando as células fetais das maternas. Tal modelo terá aplicação direta, principalmente porque estes são animais que apresentam problemas em relação ao seu desenvolvimento. Com o auxílio deste modelo, pretende- se verificar o transporte de substâncias entre a mãe e o feto via endocitose, pela imunolocalização das proteínas chamadas de caveolinas. Para tanto foram utilizados 06 bovinos clonados e 30 bovinos de inseminação artificial (IA) com idade até 90 dias de gestação, os quais tiveram seu desenvolvimento interrompido mediante abate humanitário das receptoras e ovariosalpingohisterectomia, com posterior recuperação do útero gestante. Foram coletados os placentônios e o cório. Uma parte das amostras foi recortada e fixada, por imersão, em solução de parafolmaldeído a 4% ou formoldeído a 10% em tampão fosfato de sódio (PBS) a 0,1M pH 7.4, solução de Zamboni (4% de paraformoldeído, 15% de ácido pícrico, em tampão fosfato de sódio a 0,1M pH 7.4), metacarn (60% de metanol, 30% de clorofórmio, e 10% de ácido acético glacial), para verificação da morfologia e realização de imuno-histoquímica para as proteínas caveolinas -1 e -2 (CAV -1 e CAV-2). As caveolinas -1 foram localizadas nos vilos fetais e maternos, mas sua marcação mais forte foi observada no estroma endometrial. As caveolinas -2 tiveram marcação positiva no trofoblasto e membrana corioalantoide, e, especificamente em célula trofoblástica gigante binucleada. Sendo assim, os resultados mostram que a proteína CAV-1 teve uma maior expressão em relação a proteína CAV-2 e que as proteínas CAV-1 e -2 são parte da composição das cavéolas, sendo .
Abstract: The transgenic application of green fluorecent protein (GFP) as fetal cell marker on cattle cloned placenta could provide an exclusive model for studying the morphologic and immunologic maternal-fetal interactions, providing information about its mapping, distinguishing the fetal from maternal cells. This model will have direct application, mainly because these are animals that present problems during its development. With this model's support, we intend to verify the substances transport between mother and fetus during endocytocis, through the immunolocalization of protein named caveolae. For these, we used 06 cloned bovine and 30 cattle samples of artificial insemination (AI) with 90 days of pregnancy, which had been their development interrupted by humanitarian slaughter of the recipient and recovery of the pregnant uterus. We collected the placentome and the chorion. A part of the samples will be cutted and fixed, by immersion, on a solution containing 4% of parafomaldehyde or 10% of formaldehyde on a sodium phosphate buffer (PBS) at 0,1M pH 7.4, Zamboni solution (4% of paraformaldehyde, 15% of picric acid, on sodium phosphate buffer 0,1M pH 7.4), metacarn (60% of metanol, 30% of chloroform, and 10% glacial acetic acid), for morphologic and immunohistochemistry verification for caveolinas proteins -1 and -2 ( -1 CAV and CAV- 2). The caveolinas -1 were found in fetal and maternal villi , but its strongest staining was observed in the endometrial stroma . The caveolinas -2 had positive staining in trophoblast and chorioallantoic membrane , and specifically in giant trophoblastic binucleated cell . therefore the results were compared between cloned cattle and from AI or natural mating, for assisting on detection of the reason of many placental alterations, embryonic losses, spontaneous abortion, post-natal mortality and large offspring syndrome on laboratory-manipulated animals. The result suggests that the proteins caveolins -1 and ...
Mestre
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30

Albuquerque, João Pedro de. "Estratégias para aumento da concentração de progesterona durante o desenvolvimento do folículo ovulatório em vacas holandesas em lactação submetidas à inseminação artificial em tempo fixo /." Botucatu, 2015. http://hdl.handle.net/11449/136114.

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Abstract:
Orientador: José Luiz Moraes Vasconcelos
Banca: João Carlos Pinheiro Ferreira
Banca: Mario Binelli
Resumo: O presente estudo avaliou se a concentração de P4 durante o desenvolvimento do folículo ovulatório em protocolo a base de P4/BE e com uma aplicação de GnRH em seu início interfere na prenhez à IATF em vacas Holandesas em lactação. A hipótese é que vacas com maior P4 no dia da aplicação da 1ª dose de PGF2α terão maior fertilidade. Para alterar a P4 os animais (n=594) foram distribuídos aleatoriamente em dois grupos para receberem um ou dois dispositivos intravaginais de P4 (CIDR®, Zoetis, SP, Brasil). O protocolo utilizado foi: no d-11 inserção de 1 CIDR (novo ou previamente usado por 9 dias) + aplicação de 2mg i.m. de BE (Gonadiol®, Zoetis, SP, Brasil) + 100mcg i.m. de GnRH (Cystorelin®, Merial, SP, Brasil); d-4, aplicação de 25mg i.m. de Dinoprost (Lutalyse®, Zoetis, SP, Brasil); d-2, aplicação de 25mg i.m. de Dinoprost + 1mg i.m. de ECP (ECP®, Zoetis, SP, Brasil) + retirada do dispositivo de P4; d0, IATF. Os animais do grupo 2CIDR receberam um CIDR adicional no d-11, o qual foi retirado no d-4. Nos d-11 (n= 117), d-4 (n= 351), d0 (n= 214) e d10 (n= 72) foram colhidas amostras de sangue para determinação da concentração de P4. A P/IA foi determinada através de US nos d32 (DG1) e d60 (DG2). Dados binários foram analisados pelo PROC GLIMMIX, e os dados contínuos pelo PROC MIXED do SAS (foi considerada diferença significativa se P<0,05 e tendência se P<0,1). A P4 não diferiu entre os tratamentos no d-11 (1CIDR= 4,2±0,4 ng/ml; 2CIDR= 4,5± 0,4ng/ml; P>0,1), e no d-4 (1CIDR= 3,5±0,2ng/ml; 2CIDR= 3,8±0,2 ng/ml; P>0,1), porém foi detectada interação entre tratamento e presença de CL no início do protocolo na P4 no d-4 (sem presença de CL e 1CIDR= 2,7±0,3ng/ml; 2CIDR= 3,6±0,3ng/ml, com presença de CL e 1CIDR= 4,3±0,3ng/ml; 2CIDR= 4,0±0,3ng/ml; P<0,05). Não houve diferença na prenhez a IATF e nas perdas gestacionais entre os tratamentos [DG1: 1CIDR= 20,0 ...
Abstract: The present study evaluated if P4 concentration during ovulatory follicle development in a timed artificial insemination (TAI) protocol based on P4/E2 affects pregnancy per AI in lactating Holstein cows. Our hypothesis is that cows that present higher P4 concentration at PGF2α administration have also higher fertility. To alter P4, animals (n=594) were randomly assigned to receive one or two intravaginals devices of P4 (CIDR®, Zoetis, SP, Brazil). TAI protocol utilized was: d-11 intravaginal device of P4 (new or previously used by 9 days) + 2mg im EB (Gonadiol®, Zoetis, SP, Brazil) + 100mcg im GnRH (Cystorelin®, Merial, SP, Brazil); d-4, 25mg im Dinoprost (Lutalyse®, Zoetis, SP, Brazil); d-2, 25mg im Dinoprost + 1mg im ECP (ECP®, Zoetis, SP, Brazil) + CIDR removal; d0, TAI. Animals in the group 2CIDR received an adicional CIDR at d-11, which was removed at d-4. At d-11 (n=117), d-4 (n=351), d0 (n=214) and d10 (n=72), blood samples were taken from cows for P4 concentration measurements. Pregnancy per AI was determined by ultrasound at d32 (DG1) and d60 (DG2). The binomial data were analyzed using PROC GLIMMIX and continuous data using PROC MIXED of SAS. An effect was considered significant when P<0.05 and tendency when P<0.1. P4 did not differ among treatments at d-11 (1CIDR=4.2±0.4ng/ml; 2CIDR=4.5±0.4ng/ml; P>0.1), and at d-4 (1CIDR=3.5±0.2ng/ml; 2CIDR=3.8±0.2 ng/ml; P>0.1). An interaction was detected between treatment and CL presence at the beginning of TAI protocol in P4 at d-4 (without CL and 1CIDR=2.7±0.3ng/ml; 2CIDR= 3.6±0.3ng/ml, with CL and 1CIDR=4.3±0.3ng/ml; 2CIDR= 4.0±0.3ng/ml; P<0.05). There was no difference among treatments in pregnancy per AI and pregnancy loss between DG1 and DG2 [DG1: 1CIDR= 20,0% (81/310) vs. 2CIDR= 15,7% (65/284); DG2: 1CIDR= 18,2% (74/310) vs. 2CIDR= 13,8% (57/283); Pregnancy loss: 1CIDR= 14,1% (7/81) vs. 2CIDR= 11,5% (7/64); P>0,1]. 37,0% (28/63)...
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31

Gordon, Miriam Bronwen. "Strategies to improve ovulation synchronization/timed artificial insemination protocol to increase pregnancy rate in dairy cattle." Thesis, University of British Columbia, 2011. http://hdl.handle.net/2429/37788.

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Physiological stressors of high milk production and intensive management systems affect fertility and pregnancy rates (PR) in lactating dairy cows. A field study was conducted on dairy farms in the Fraser Valley of British Columbia to benchmark current reproductive performance and issues that impact local dairy farms. The results indicated a substantial reduction in reproductive performance due to inaccurate estrus detection, fertilization/ovulation failure, and embryonic mortality. Ovsynch timed artificial insemination (TAI) protocol is used for the induction and synchronization of ovulation in cattle, reducing the need for estrus detection. However, PR to Ovsynch TAI are still low. Strategies to modify Ovsynch TAI protocol were investigated in this study to increase PR. In the first experiment, Ovsynch was compared with a pre-synchronization treatment, using PGF₂α before Ovsynch TAI to improve synchronization rates, and to a treatment of GnRH given 6 d after Ovsynch TAI, to reduce embryonic loss. Although no differences in PR were observed between treatments, days in milk in cows and age and weight in heifers affected PR. In the second experiment, the effects of pLH or hCG vs. GnRH in an Ovsynch TAI protocol were compared. Progesterone concentrations in pregnant cows were greater in the hCG group on days 7, 11, and 14, and greater in the pLH group on day 11 after breeding than GnRH group. There were no differences in synchronization rates or PR between treatments. High protein diets have been associated with reduced PR. Therefore, in the third experiment, cows either continued on a typical high protein diet, which was fed from calving, or switched to a lower protein diet, beginning 7 d before Ovsynch TAI and continued until pregnancy diagnosis. First and second lactation cows fed the low protein diet tended to have greater PR than cows fed the high protein diet. There were no differences in synchronization rates and progesterone concentrations between diets. Cows fed the lower protein diet had lower milk urea nitrogen and lower average daily milk production during treatment. Costs associated with treatments, labour, and producer compliance should be considered before recommending ovulation synchronization Ovsynch TAI protocol to dairy producers.
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32

Ojomo, Christian Olafimihan. "The Feasibility of Artificial Insemination of Dairy Cattle Managed by Fulani Tribesmen in Kaduna State, Nigeria." DigitalCommons@USU, 1987. https://digitalcommons.usu.edu/etd/153.

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This study sought to determine: (a) the essential elements of a viable artificial insemination program for the Fulani Tribesmen in Kaduna State, Nigeria, and (b) to determine if the essential elements of a viable artificial insemination program exist in Kaduna State, Nigeria. This study was conducted from April 15 to May 15, 1985, in the Artificial Insemination (AI) Subcenters of Zaria, Katsina, Kabomo, Kaduna, Ikara, Zonkwa, Kurmin-Biri, and Kauranjuli. The data presented in this study were collected by personal interviews with Fulani Tribesmen. The population of this study was from a partial list of Fulani Tribesmen who have had AI performed on their dairy cattle by the cooperative inseminators in the subcenters. The statistical analysis showed an overview of herdsmen reactions to each question. The use of additional statistical tests to determine the degree of significance was not appropriate because the respondents were not randomly selected. The writer did not know in advance the number of Fulani Tribesmen that constituted the total population of the AI system in the subcenters. Noneconomic analysis of this research study includes five linked essential elements of a viable AI program. These elements are: (1) high performance bulls with quality semen, (2) skilled dependable AI technicians, (3) healthy cows, (4) functional communication and transportation resources, and (5) cooperative and informed farmers. This study concluded that four of the five essential elements for a viable AI program currently do not exist for the Fulani Tribesmen in Kaduna State, Nigeria. As a result of this study, it was determined a viable AI program for the Fulani Tribesmen in Kaduna State, Nigeria, is not feasible under the present situation.
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33

Chung, Jin-Tae 1961. "Activation of bovine oocytes following intracytoplasmic sperm injection (ICSI)." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21528.

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The objective of this study was to develop a reliable method for intracytoplasmic sperm injection (ICSI) in bovine oocytes. Oocytes recovered from abattoir-derived ovaries were centrifuged for 5 min at 6000xg to facilitate sperm injection. Sperm were pre-treated in vitro with 5mM dithiothreitol (DTT), and diluted (approximately 1:5) with 5% polyvinylpyrrolidone (PVP) in 0.9% saline. After sperm injection, various activation procedures were compared. Initially, 3 h after activation with 5muM Ionomycin (A23187), oocytes with second polar bodies were selected and treated with 1.9mM 6-dimethylaminopurine (DMAP). The cleavage rate of sperm-injected oocytes treated with Ionomycin and DMAP was higher than with Ionomycin alone (62.1 vs. 27.3%, p < 0.05). In sham-injected control oocytes treated with Ionomycin and DMAP, the cleavage rate was approximately six times higher than that of oocytes treated with Ionomycin alone (44.3 vs. 7.4%, p < 0.001). Upon examination 16 h after ICSI, pronuclear formation was observed in 33 of 47 (70.2%) DMAP-treated oocytes. Two pronuclei were present in 18 of 33 (54.6%), while one and three pronuclei were seen in 8 of 33 (24.2%) and 7 of 33 (21.2%), respectively. In sham-injected DMAP-treated control oocytes, 6 of 15 (40.0%) had one pronucleus while 9 of 15 (60.0%) had two pronuclei. Since a single Ca2+ stimulation provided insufficient activation and DMAP treatment could result in triploidy, activation by multiple Ca2+ stimulations following ICSI was tested. Three Ca2+ stimulations were given at 30-min intervals. Pronuclear formation was observed in 16 of 41 (39.0%) oocytes at 16 h after sperm injection, with one and two pronuclei found in 4 of 16 (25.0%) and 12 of 16 (75.0%), respectively. Although one pronucleus was formed in 3 of 33 (9.1%) sham-injected control oocytes treated with three Ca2+ stimulations, two pronuclei were not seen in any of these oocytes. Due to the low rate of pronuclear formation after 5muM Ionomycin, 50muM
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34

Peeler, Iris Dawn. "Synchronization and Resynchronization of Ovulation and Timed Insemination in Lactating Dairy Cows and Heifers." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/9880.

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This study was conducted to evaluate the efficacy of intravaginal progesterone (P4) inserts (CIDR) in synchronization protocols combined with timed artificial insemination (TAI) as related reproductive performance. In the first study, heifers were synchronized with CIDR inserts followed by TAI. Heifers in the estradiol cypionate (ECP) group were synchronized with a combination of ECP, CIDR, prostaglandin (PGF2α), and ECP (CIDR-ECP), while the gonadotropin-releasing hormone (GnRH) group was synchronized using a combination of ECP, CIDR, PGF2α, and GnRH (CIDR-GnRH). All heifers were bred at either 48, 56, or 72 hours (h) after CIDR removal. Overall pregnancy rate (PR) for synchronized heifers was 60.1%, and embryo survival rate (ESR) was 98%. Pregnancy rate for CIDR-ECP treated heifers was influenced by artificial insemination (AI) time. In conclusion, ECP or GnRH may be used effectively in a CIDR-based TAI program in heifers. In the second study, cows were synchronized with CIDR devices or Ovsynch. The CIDR group received a combination of ECP, CIDR, PGF2α, and GnRH, while the Ovsynch group was synchronized using a combination of GnRH and PGF2α. Cows were bred at either 0, 8, or 24 h after the final GnRH injection. Overall PR for first service was 30.5% with ESR of 82.8%. Overall resynchronization PR was 35.1% with an ESR of 84.8%. In conclusion, Ovsynch and CIDR-based protocols are equally effective in synchronizing ovulation in a TAI program and resulted in comparable PR.
Master of Science
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35

Wilson, Lawriston A. II. "Prediction of Fertility of Virginia Beef Heifers Using Expert Systems Technology." Thesis, Virginia Tech, 1996. http://hdl.handle.net/10919/36730.

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An expert system to predict the fertility of beef heifers was developed using the A.I. Toolkit KAPPA-PC 2.33. The knowledge base was developed from scientific literature and from a beef cattle reproduction expert. The expert system computes an evaluation age, age both at the start and end of the breeding season, and weight per day of age to classify a heifer as having either a 3LOW2, 3GOOD2, or 3EXCELLENT2 likelihood of conception. The expert system summarizes the information that is entered into the computer and creates a text file of the summary. It also gives explanations for every prediction to help identify and alleviate any problem areas that may affect a heifer1s ability to reproduce. The program requires an IBM compatible computer installed with Windows 3.13 or greater. From simulated data for purebred or crossbred British cattle, there was 72% prediction agreement between the expert system and the expert. From analysis of historical data of Hereford-Angus crossbred cattle, heifers categorized as 3LOW2 and 3GOOD2 had significantly higher observed pregnancy rates than expected for each category. There was no significant difference between observed and expected pregnancy rates for heifers in the 3EXCELLENT2 category. Pregnancy rates for post-weaning and pre-breeding evaluations for the 3LOW2 heifers were found to be lower from the combined 3GOOD2 and 3EXCELLENT2 heifers at P=.03 and P=.06 respectively. Observed successful calving rates for heifers categorized as 3LOW2, 3GOOD2, and 3EXCELLENT2 did not differ significantly from the expected calving rates for each category.
Master of Science
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36

Phillips, Nancy Jane. "A study of the in vitro spermatozoal characteristics affecting the likelihood of conception following artificial insemination of Australian cattle /." [St. Lucia, Qld.], 2003. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17477.pdf.

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37

Oliveira, Letícia Zoccolaro [UNESP]. "Utilização de diferentes touros na IATF: características seminais e suas relações com as taxas de fertilidade a campo." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/105900.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Tem sido frequentemente demonstrado que variadas taxas de concepção podem ser obtidas de acordo com o sêmen utilizado, evidenciando uma importante variabilidade individual do reprodutor com relação à fertilidade. Além disso, as grandes dimensões dos rebanhos, associado ao intenso e crescente uso dos protocolos de IATF no Brasil, tem estimulado, cada vez mais, a prática do descongelamento simultâneo de diversas palhetas de sêmen em um mesmo descongelador. Entretanto, sob essas condições, o banho-maria do descongelador poderia atuar como ambiente de incubação para o sêmen, o que poderia influenciar a viabilidade do espermatozoide. Assim, o presente estudo teve por objetivos: 1) determinar o efeito da sequência de inseminação, após descongelamento simultâneo de diversas palhetas de sêmen, na taxa de concepção e na qualidade seminal; 2) investigar a fertilidade in vivo, bem como diversas características espermáticas in vitro, do sêmen de diferentes reprodutores utilizados no mesmo programa de IATF; 3) identificar, dentre as diversas análises laboratoriais realizadas, o grupo de características espermáticas consideradas importantes na predição da taxa de concepção. Para tal, o presente experimento foi realizado em duas etapas. A primeira etapa consistiu em um estudo a campo delineado para determinar a taxa de concepção após IATF de fêmeas pós-parto da raça Nelore (n=947), utilizando sêmen de três partidas de cada um dos três touros da raça Angus (n=9). A segunda etapa consistiu em um estudo laboratorial delineado para investigar diversas características espermáticas das doses de sêmen utilizadas no respectivo programa de IATF, utilizando as mesmas condições de descongelamento do estudo a campo. As seguintes análises laboratoriais foram realizadas: análise computadorizada do movimento...
It has been reported that different conception rates can be obtained according to the semen used, indicating a significant variability regarding sire fertility. Furthermore, the large size of reproductive herds associated with the intense use of Timed-AI protocols in Brazil, has stimulated the routine practice of simultaneous thawing of multiple semen straws in the same thawing-bath. However, under these conditions, the thawing-bath could act as an incubator environment for the semen, which could influence the sperm viability. Thus, this study aimed to: 1) determine the effect of sequence of insemination after simultaneous thawing of multiple semen straws on conception rate and semen quality; 2) investigate the in vivo fertility, as well as several in vitro sperm characteristics, from different sires used in the same Timed-AI program; 3) identify, among the several in vitro sperm variables evaluated in laboratory, the group of sperm characteristics considered important in the prediction of conception rate. Hence, this study was conducted in two experiments. The first experiment was a field study designed to determine conception rate after Timed-AI of suckled multiparous Nelore cows (n = 944) using three semen batches from three Angus bulls (n = 9). The second experiment was a laboratory study designed to investigate several sperm characteristics of semen used in the Timed-AI program, using the same thawing conditions applied in the field experiment. The following laboratory analyses were performed: computer assisted semen analysis, hypo-osmotic swelling test, sperm resistance after 2 hours of thermal incubation, sperm morphology, integrity of plasma and acrosomal membranes, plasma membrane stability, lipid peroxidation, sperm morphology and chromatin condensation. According to the present experiment, it was concluded that... (Complete abstract click electronic access below)
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38

Oliveira, Letícia Zoccolaro. "Utilização de diferentes touros na IATF : características seminais e suas relações com as taxas de fertilidade a campo /." Jaboticabal, 2012. http://hdl.handle.net/11449/105900.

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Orientador: Vera Fernanda Martins Hossepian de Lima
Coorientador: Rubens Paes de Arruda
Coorientador: Ricarda Maria dos Santos
Banca: Gisele Zoccal Mingoti
Banca: Sony Dimas Bicudo
Banca: Ed Hoffmann Madureira
Banca: Eneiva Carla Carvalho Celeghini
Resumo: Tem sido frequentemente demonstrado que variadas taxas de concepção podem ser obtidas de acordo com o sêmen utilizado, evidenciando uma importante variabilidade individual do reprodutor com relação à fertilidade. Além disso, as grandes dimensões dos rebanhos, associado ao intenso e crescente uso dos protocolos de IATF no Brasil, tem estimulado, cada vez mais, a prática do descongelamento simultâneo de diversas palhetas de sêmen em um mesmo descongelador. Entretanto, sob essas condições, o banho-maria do descongelador poderia atuar como ambiente de incubação para o sêmen, o que poderia influenciar a viabilidade do espermatozoide. Assim, o presente estudo teve por objetivos: 1) determinar o efeito da sequência de inseminação, após descongelamento simultâneo de diversas palhetas de sêmen, na taxa de concepção e na qualidade seminal; 2) investigar a fertilidade in vivo, bem como diversas características espermáticas in vitro, do sêmen de diferentes reprodutores utilizados no mesmo programa de IATF; 3) identificar, dentre as diversas análises laboratoriais realizadas, o grupo de características espermáticas consideradas importantes na predição da taxa de concepção. Para tal, o presente experimento foi realizado em duas etapas. A primeira etapa consistiu em um estudo a campo delineado para determinar a taxa de concepção após IATF de fêmeas pós-parto da raça Nelore (n=947), utilizando sêmen de três partidas de cada um dos três touros da raça Angus (n=9). A segunda etapa consistiu em um estudo laboratorial delineado para investigar diversas características espermáticas das doses de sêmen utilizadas no respectivo programa de IATF, utilizando as mesmas condições de descongelamento do estudo a campo. As seguintes análises laboratoriais foram realizadas: análise computadorizada do movimento... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: It has been reported that different conception rates can be obtained according to the semen used, indicating a significant variability regarding sire fertility. Furthermore, the large size of reproductive herds associated with the intense use of Timed-AI protocols in Brazil, has stimulated the routine practice of simultaneous thawing of multiple semen straws in the same thawing-bath. However, under these conditions, the thawing-bath could act as an incubator environment for the semen, which could influence the sperm viability. Thus, this study aimed to: 1) determine the effect of sequence of insemination after simultaneous thawing of multiple semen straws on conception rate and semen quality; 2) investigate the in vivo fertility, as well as several in vitro sperm characteristics, from different sires used in the same Timed-AI program; 3) identify, among the several in vitro sperm variables evaluated in laboratory, the group of sperm characteristics considered important in the prediction of conception rate. Hence, this study was conducted in two experiments. The first experiment was a field study designed to determine conception rate after Timed-AI of suckled multiparous Nelore cows (n = 944) using three semen batches from three Angus bulls (n = 9). The second experiment was a laboratory study designed to investigate several sperm characteristics of semen used in the Timed-AI program, using the same thawing conditions applied in the field experiment. The following laboratory analyses were performed: computer assisted semen analysis, hypo-osmotic swelling test, sperm resistance after 2 hours of thermal incubation, sperm morphology, integrity of plasma and acrosomal membranes, plasma membrane stability, lipid peroxidation, sperm morphology and chromatin condensation. According to the present experiment, it was concluded that... (Complete abstract click electronic access below)
Doutor
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39

Hill, Scott L. "Presynchronizing injections of prostaglandin F[subscript]2alpha[subscript] or prostaglandin F[subscript]2alpha[ subscript + Gonadotropin-releasing hormone before a fixed time artificial insemination CO-Synch + CIDR program in suckled beef cows." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/15309.

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Master of Science
Department of Animal Sciences and Industry
Jeffrey S. Stevenson
We hypothesized that pregnancy outcomes may be improved by inducing luteal regression, ovulation, or both before a control CO-Synch + CIDR program (100 mcg GnRH i.m. [GnRH-1] and insertion of a progesterone-impregnated intravaginal controlled internal drug release [CIDR] insert on d -10, 25 mg PGF2alpha (PG) i.m. and CIDR insert removal on d -3, and 100 mcg GnRH i.m. [GnRH-2] and timed AI [TAI] on d 0) in suckled beef cows. This hypothesis was tested in 2 experiments, in which cows were treated with either PG or PG + GnRH before initiating a control CO-Synch + CIDR program to increase the proportion of cows starting the program in a low (< 1 ng/mL; Exp. 1) or high (≥ 1 ng/mL; Exp. 2) progesterone status, respectively. Blood was collected before each injection for later progesterone analyses. In Exp. 1, cows at 9 locations (n = 1,537) were assigned to either: (1) control or (2) PrePG (same as control with a PG injection on d -13). The PrePG cows had larger (P < 0.05) follicles on d -10 and more (P < 0.05) ovulated after GnRH-1 than controls (60.6 vs. 36.5%). Incidence of estrus between d -3 and 0 was greater (P < 0.05) for treated multiparous cows than multiparous controls and treated and control primiparous cows (74.1 vs. 64.3, 58.6, and 59.1%, respectively). In Exp. 2, cows at 4 locations (n = 803) were assigned to: (1) control (same as Exp. 1) or (2) PrePGG (same as control with PG injection on d -20 and GnRH injection on d -17. Cows with BCS > 5.0 or ≥ 70 d postpartum at TAI were more (P < 0.05) likely to become pregnant than thinner cows or those with fewer days postpartum. Treated cows in both experiments were more (P < 0.05) likely than controls to have luteolysis after initial PG injections and reduced (P < 0.05) serum progesterone. In both experiments, pregnancy rates at d 35 did not differ between treatment and control; however, cows classified as anestrous before d -10, but with elevated progesterone on d -10, had increased (P < 0.05) pregnancy outcomes than remaining anestrous cows with low progesterone concentrations. In summary, luteal regression and ovulation were enhanced by treatments before the 7 d CO-Synch + CIDR program; however, pregnancy per TAI was not improved.
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40

Harstine, Bo R. "Novel Approaches to Positively Impact the Early Life Physiology, Endocrinology, and Productivity of Bulls." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1480521360099455.

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41

Van, Niekerk Guillaume Stefanus. "The effect of different intravaginal progesterone doses on the conception rate of beefmaster cows and heifers following fixed time artificial insemination." Thesis, [Bloemfontein?] : Central University of Technology, Free State, 2013. http://hdl.handle.net/11462/158.

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Thesis (M. Tech. (Agriculture)) - Central University of Technology, Free state, 2013
The study was carried out to establish whether or not a decrease in the progesterone concentration of an intravaginal device used to synchronize oestrous in Beefmaster heifers and cows would lead to an increase in conception rates. The study evaluated the effect of different intravaginal progesterone device doses on the conception rates of Beefmaster cows and heifers following fixed time artificial insemination (FTAI). A total of 100 stud Beefmaster cows (Cow group) and 100 stud Beefmaster heifers (Heifer group) were used in the study. The animals were year round grazing residents of the farm Oribilaagte near the town of Vrede in the Free State province of South Africa. The Cow and Heifer groups were split into four experimental groups, respectively, and treated with either a 0.5 g, 1.0 g, 1.9 g or 1.9 g re-used intravaginal progesterone device during the spring synchronization program (P4 device insertion and 2 mg i.m. oestradiol benzoate treatment on d 0, 250 μg s.c. PGF2_ treatment on d 7, P4 device removal on d 8, 1 mg i.m. oestradiol benzoate treatment on d 9, and FTAI on d 10). Blood samples were taken on the day of intravaginal insert removal (d 8), and on the day of FTAI (d 10), to monitor the blood serum P4 concentrations (solid phase RIA analysis) between the experimental groups. The experimental groups were examined for pregnancy 5 months post AI by means of rectal palpation. The Cow group recorded a pregnancy rate of 65%, 75%, 67% and 68% for the 0.5 g, 1.0 g, 1.9 g and 1.9 g re-used intravaginal progesterone device groups respectively. The Heifer group recorded a pregnancy rate of 19%, 39%, 41% and 47% for the 0.5 g, 1.0 g, 1.9 g and 1.9 g re-used intravaginal progesterone device groups respectively. The study concluded that a decrease in the progesterone concentration in the intravaginal device did not affect the serum progesterone concentrations in the Heifer and Cow groups on the day of the FTAI, and did not negatively affect the synchronization program. The study further concluded that, although a decrease in the progesterone concentration in the intravaginal device did not statistically influence the conception rates in the Heifer and Cow groups, the Cow group did record a higher numerical conception rate when the progesterone concentrations in the intravaginal devices were reduced.
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42

Buttrey, Brad Sterling. "Human chorionic gonadotropin and gonadotropin-releasing hormone influence pregnancy survival and resynchronized ovulation before timed artificial insemination in Holstein cattle." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/542.

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43

Pitt, Colin John. "Lowering Sperm Dose Rates in Frozen Semen for Bovine Artificial Breeding." The University of Waikato, 2007. http://hdl.handle.net/10289/2232.

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The New Zealand Dairy industry relies on artificial breeding to produce high genetic merit replacement stock. Proven bull semen is extended and preserved as either ambient temperature product or as frozen doses. High fertility is essential to maintain synchronicity of lactation with the spring surge of grass growth. To improve efficiency in the utilization of the very best bulls producers try to lower sperm dose rates without compromising fertility. Livestock Improvement Corporation's (LIC) Long Last Liquid ™ (LLL) is most commonly used during the peak season and is their most important product. However, shortfalls and specifically targeted matings are met with frozen semen. Lowering sperm dose rates in both liquid and frozen semen maximises the usage of elite sires increasing genetic gain, lowering overheads and garnering premium prices for the semen producer. A product for improving frozen semen technology was developed whereby a discrete quantity of pretreated semen was placed alongside a beneficial post-thawing redilution medium in a standard semen straw. This emulated a larger-scale process developed to freeze semen in times of low demand and redilution into the LLL form for use as an ambient temperature product. This rediluted product has been proved to enhance semen survival and to allow fertility to be maintained at sperm dose rates lower than the widely accepted standard for frozen semen. The physical packaging of the semen into the industry standard single dose straw in a configuration that separated incompatible components was novel. This configuration was essential to prevent damage to the sperm during the freezing process from low solubility components in the post-thaw redilution medium. Separation between the semen and diluent within the straw was achieved by the introduction of a gas partition or air bubble between the two liquids. A large-scale field trial showed that the new product could produce savings of up to 25% of the sperm needed for a semen dose to achieve equivalent fertility. Furthermore, the production cost per dose was lowered in comparison to the standard semen processing system used at LIC.
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44

Davoodi, Saeideh. "The effect of expression of estrus at artificial insemination on target genes in the endometrium, conceptus and corpus luteum of beef cows." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/52973.

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The aim of this study was to test the effect of expression of estrus at artificial insemination (AI) on the endometrium, conceptus and corpus luteum (CL) gene expression. Twenty-three multiparous non-lactating Nelore cows were enrolled on an estradiol (E2) and progesterone (P4) based timed-AI protocol (AI = d 0), then slaughtered for endometrium, CL and conceptus collection on d 19. Body condition score (BCS), blood samples and ultrasound examination was performed on d 0, 7 and 18 of the experiment followed by RNA extraction and quantitative reverse transcription polymerase chain reaction (qRT-PCR) analysis of 58 target genes. Data was checked for normality and analysed by ANOVA for repeated measures using proc GLM, MIXED and UNIVARIATE. Estrous expression had no correlation with parameters such as BCS, pre-ovulatory follicle and CL diameter, P4 concentration in plasma on d 7 and 18 after AI and IFN-tau concentration in the uterine flushing (P > 0.05); however, a significant increase was observed in conceptus size (P = 0.02; 38.3 ± 2.8 vs 28.2 ± 2.9). The majority of transcripts affected by estrous expression in the endometrium belong to the immune system and adhesion molecule family (MX1, MX2, MYL12A, MMP19, CXCL10, IGLL1 and SLPI) (P ≤ 0.05). Genes related to apoptosis, P4 synthesis and prostaglandin receptor were down-regulated (CYP11A, BAX and PGF2α receptor) (P < 0.05) in the CL tissue of cows in estrus. In addition, four genes were identified as differentially expressed in the 19 old conceptus from cows observed in estrous (ISG15, PLAU, BMP15 and EEF1A1; P<0.05). There was also a significant effect of P4/d7 mainly affecting immune system, adhesion molecules and wnt signaling pathway of endometrium (IGLL1, MX2, SLPI, TRD, APC, WNT2, GLYCAM1 and MYL12A) (P<0.05). A significant interaction between estrus expression and P4 concentration on d 7 was more pronounced in immune system genes (MX1, MX2, TRD, SLPI and IGLL1; P<0.05). This study demonstrated that estrous expression at the time of AI, in spite of ovulation being induced by E2, could alter the gene expression profile in reproductive tissues during the pre-implantation phase.
Land and Food Systems, Faculty of
Graduate
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45

Crespilho, André Maciel. "Efeito do meio diluidor e da dose inseminante sobre a congebilidade e fertilidade do sêmen bovino utilizado em programas de inseminação artificial em tempo-fixo(LATF) /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/98227.

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Orientador: Frederico Ozanam Papa
Banca: João Carlos Pinheiro Ferreira
Banca: Alício Martins Junior
Resumo: A despeito das inúmeras variáveis que influenciam direta e indiretamente a fertilidade das fêmeas bovinas, a qualidade das amostras seminais exerce um papel importante na determinação das taxas de concepção dos programas de inseminação artificial. Os objetivos dessa pesquisa foram comparar a efetividade de dois diluidores de criopreservação de sêmen bovino no processamento de amostras seminais apresentando diferentes concentrações espermáticas em relação aos índices de congelabilidade determinados laboratorialmente (Experimento I) e as taxas de concepção proporcionadas por cada metodologia quando utilizada em programas de inseminação artificial em tempo fixo (IATF) em bovinos (Experimento II). No Experimento I foram utilizados 14 ejaculados de diferentes touros da raça Nelore. Cada ejaculado foi fracionado em oito alíquotas iguais, submetidas a criopreservação com os diluidores Tris-gema de ovo-frutose (meio TRIS) e MKA nas concentrações de 12, 25, 50 e 100 milhões de espermatozóides totais por mililitro de meio, formando oito grupos experimentais em função das variáveis diluidor e concentração. As amostras foram descongeladas a 46 ºC por 20 segundos, avaliando-se os padrões de motilidade através do método computadorizado (CASA), integridade de membrana plasmática (IMP), resistência ao teste de termorresistência rápido (TTR) e taxa de recuperação e IMP após seleção espermática pela técnica de swim-up. Para o Experimento II foram selecionados sete touros utilizados no Experimento I, obtendo-se um ejaculado de cada animal por eletroejaculação...(Resumo completo, clicar acesso eletrõnico abaixo)
Abstract: Although there are many variables which directly or indirectly influence female bovine fertility, the quality of sperm samples plays a important role in the determination of conception rates in artificial insemination programs. The aim of the present study was to compare the efficiency of two bovine semen extenders for sperm freezing with different spermatic concentrations in the freezability determined by lab tests (Experiment I), and conception rates after fixed time artificial insemination (FTAI; Experiment II). In Experiment I 14 ejaculates of different Nelore bulls were used. Each ejaculate was splitsampled in to eight equal parts and then submitted to cryopreservation with Tris-egg yolk fructose (TRIS) and MKA extenders, at concentrations of 12, 25, 50 and 100 millions spermatozoa per milliliter forming eight experimental groups. The samples were thawed at 46 ºC for 20 seconds, and the following parameters were evaluated: sperm motility and movement (by computer-assisted semen analysis - CASA), sperm membrane integrity (SMI), resistance to the fast thermoresistance test (TT), recovery rate and sperm membrane integrity after sperm selection through swim-up technique. Seven of 14 bulls used in Experiment I were selected for Experiment II, and semen was collected from each of the animals by electroejaculation. The seven ejaculates obtained were mixed (semen pool) and cryopreserved, thus forming eight experimental groups according to the freezing extenders and sperm concentrations/straws: TRIS 12, 25, 50 and 100, and MKA 12, 25, 50 and 100...(Complete abstract, click electronic address below)
Mestre
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46

Romanzini, Eliéder Prates. "Economic evaluation, strategy and prediction studies of results into beef cattle production using different scenarios /." Jaboticabal, 2019. http://hdl.handle.net/11449/183167.

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Abstract:
Orientador: Euclides Braga Malheiros
Resumo: A pecuária de corte brasileira tem sido pressionada no sentido de cada vez obter melhores resultados, o que força os proprietários a utilizar práticas e manejos específicos, os quais possibilitarão a manutenção dentro da atividade. Este estudo teve como objetivos avaliar o uso de inteligência artificial, mais especificamente redes neurais artificiais (RNA), para predizer resultados futuros tanto da produção de pasto quanto animal. Determinar dentre diversos cenários de recria e terminação de bovinos de corte em pastagens tropicais, qual foi o melhor cenário no que diz respeito aos resultados econômicos. Avaliar dentre diferentes doses de adubação nitrogenada, qual foi aquela que retornou melhores índices econômicos. As RNA se mostraram melhores que as regressões normalmente utilizadas para predizer as produções de pastagem (valores médios obtidos pelo uso das RNA foram 0,84; 0,78 e 0,75 para massa de forragem, porcentagens de folha e colmo, versus 0,74; 0,39 e 0,50 obtidos usando regressão linear múltipla) e animal (0,72 [RNA] e 0,67 regressão). No estudo referente aos cenários, os melhores resultados foram obtidos quando utilizado apenas sal mineral (lucratividade de 26,3%; período de “payback” simples igual à 11 ciclos e taxa interna de retorno de 9,30%) na recria dos bovinos de corte e na terminação, quando as variáveis climáticas possibilitaram via manejo de pastagem o uso de maior taxa de lotação (3,18 UA ha-1) na área. Quando avaliados os efeitos das doses de adubação n... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Brazilian beef cattle has been under pression to obtain better results, which drives owners to use specific practices and management, which will allow the maintenance within livestock. This study aimed to evaluate use of artificial intelligence, specifically artificial neural networks (ANN), to predict future results both forage and animal productions. Determine between a lot of rearing and finishing phase scenarios of beef cattle production using tropical pastures, how was the best scenario considering economic results. Evaluate between different nitrogen fertilizers levels, how was there obtained best economic indexes. The ANN was better than regressions normally used to predict forage production (mean values obtained by ANN use were 0.84, 0.78 and 0.75 for forage mass, leaf and stem percentages, versus 0.74, 0.39 and 0.50 obtained using multiple linear regression) and animal (0.72 [ANN] and 0.67 regression). Into study about scenarios, the best results were obtained when used mineral mix just (profitability of 26.3%, simple payback period equal to 11 cycles and internal return ratio of 9.30%) during rearing phase of beef cattle. During finishing phase, the best results occurred when weather variables allowed by pasture handled, the use of higher stocking rate (3.18 AU ha-1) into area. The evaluation of economic results caused by different nitrogen fertilizer levels. Allowed to say that was possible to observe that there was linear increase both on costs, and gross revenue,... (Complete abstract click electronic access below)
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47

Mendes, Catarina Neves. "Cirurgia e clínica de espécies pecuárias." Master's thesis, Universidade de Évora, 2016. http://hdl.handle.net/10174/19617.

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Abstract:
Neste relatório são, primeiramente, descritas as atividades desenvolvidas durante o Estágio Curricular do Mestrado Integrado em Medicina Veterinária da Universidade de Évora, no âmbito de clínica e cirurgia de espécies pecuárias. Pretendeu-se, depois, determinar se a suplementação de bovinos de aptidão leiteira com β-caroteno injetável contribui para reduzir o número de inseminações artificiais necessárias para uma gestação. Por outro lado avaliou-se a influência que podem ter algumas variáveis, como sejam a estação do ano ou o número de partos da vaca. Procurou-se, ainda, estudar a evolução dos teores séricos de β-caroteno nos animais suplementados e não suplementados com Dalmafertyl®, utilizando a técnica de cromatografia líquida de alta eficácia ultravioleta. A suplementação parenteral de β-caroteno, nomeadamente com Dalmafertyl®, na Primavera, mostra resultados benéficos na reprodução de vacas e novilhas de aptidão leiteira, aumentando a produtividade e diminuindo custos; ABSTRACT: LARGE ANIMAL SURGERY AND CLINICS On the following report are described the activities that took place during the Curricular Externship as part of the Veterinary Medicine Integrated Masters from University of Évora, in large animal surgery and clinics. Also, it was intended to determine if injectable β-carotene supplementation on dairy cattle can be a decreasing factor on the artificial insemination number needed to result in pregnancy. On the other hand, it was assessed its influence on some variables that can affect pregnancy, such as seasons and calving number. It has been studied the evolution of β-carotene serum levels on Dalmafertyl® supplemented and non-supplemented animals using the high-performance liquid chromatography ultraviolet detection method, as well. β-carotene parenteral supplementation using Dalmafertyl® seems to have benefic results on dairy cattle reproduction when it comes to Spring, which leads to productivity increase and cost decrease
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48

Caires, Kyle Cody. "Investigating the role of vascular endothelial growth factor in bovine testis development." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Spring2007/k_caires_050207.pdf.

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49

Ranieri, Andressa Lavezzo [UNESP]. "Efeito do meloxicam sobre as taxas de concepção de vacas da raça holandesa, de alta produção, submetidas à transferência de embrião, inseminação artificial e inseminação artificial em tempo fixo." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/98158.

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Made available in DSpace on 2014-06-11T19:29:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-07-13Bitstream added on 2014-06-13T20:38:41Z : No. of bitstreams: 1 ranieri_al_me_jabo.pdf: 416692 bytes, checksum: 8c5b1d1a825427d9d4b8b9ab52602486 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O objetivo deste trabalho foi avaliar o efeito do meloxicam sobre a taxa de concepção inicial (TCi), final (TCf) e perda gestacional (PG) de vacas Holandesas de alta produção submetidas à Transferência de Embrião (TE) Inseminação Artificial (IA) e Inseminação Artificial em Tempo Fixo (IATF). Na TE foram utilizadas, como receptoras de embrião, 492 vacas em lactação repetidoras de serviço. Na IA (n=312) e IATF (n=336) foram incluidas no estudo somente fêmeas recém paridas (com pelo menos 60 dias em lactação). Todas as fêmeas foram avaliadas e alocadas em um de dois grupos experimentais: Grupo Controle (GC) e Grupo Tratado (GT). O tratamento consistiu na administração i.m. de meloxicam injetável 2% (0,5mg/kg de peso) nos dias 7, 8 e 9 após a inovulação das receptoras de embrião, e nos dias 14, 15 e 16 da possível gestação das fêmeas submetidas a IA e IATF. Amostras de sangue foram colhidas nos D14 e D21 para posterior dosagem de progesterona (P4). O diagnóstico de gestação ocorreu aos 25-38 e 39-52 dias. O tratamento com o antiinflamatório não incrementou as TCi, TCf e tampouco diminuiu a PG em nenhuma das três biotecnologias. Contudo, observou-se que receptoras de embrião inovuladas com embriões congelados/descongelados do GT tiveram TCi e TCf menores que as do GC (GT= 25,8% v. GC=37,8%) .Não houve diferença na concentração sérica de progesterona de vacas do GC e do GT no D21. Contudo, houve efeito da estação do ano sobre as concentrações de P4 no D14 e D21 tanto na TE como na IA e IATF. Ainda, vacas gestantes apresentaram maiores concentrações de P4 que vacas não gestantes no D21. Conclui-se que o tratamento com meloxicam não incrementou as TCi, TCf, tampouco reduziu a PG de vacas Holandesas de alta produção
The aim of this study was to evaluate the effect of meloxicam on initial conception rate, final conception rate and pregnancy loss of high-producing Holstein cows submitted to embryo transfer (ET), artificial insemination (AI) and timed artificial insemination (TAI). On ET, 492 repeat breeders in milk were used as recipients. On AI (n=312) and TAI (n=336) only freshly calved cows (with at least 60 days in milk) were included in the study. The animals were evaluated and allocated in one of two experimental groups: Control Group (CG) and Treated Group (TG). The treatment consisted on administration of meloxicam 2% i.m. (0.5mg/kg of weight) on days 7, 8 and 9 after inovulation of embryo recipients, and on days 14, 15 and 16 of the possible pregnancy of females submmited to AI and TAI. Blood samples were collected on D14 and D21 for progesterone assay. The diagnosis of pregnancy was done on days 25-38 and 39-52. The treatment with the antiinflamatory did not increase initial conception rates and final conception rates, nor decreased pregnancy loss of animals in all three biotechnologies. However, recipients of TG inovulated with frozen/thawed embryos had lesser initial and final conception rates than CG (TG= 25.8% v. CG=37.8%) There was no difference on progesterone serum concentration of cows from TG and CG on D21. However, there was a season effect on P4 concentrations on D14 and 21 for ET, AI and TAI. Pregnant cows had higher P4 concentrations than non-pregnant cows. In conclusion, the treatment with meloxicam did not increase initial and final conception rates, neither decreased pregnancy loss of high producing Holstein cows
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50

Ranieri, Andressa Lavezzo. "Efeito do meloxicam sobre as taxas de concepção de vacas da raça holandesa, de alta produção, submetidas à transferência de embrião, inseminação artificial e inseminação artificial em tempo fixo /." Jaboticabal, 2012. http://hdl.handle.net/11449/98158.

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Abstract:
Orientador: Paulo Henrique Franceschini
Banca: Francisco Guilherme Leite
Banca: Erika da Silva Carvalho Morani
Resumo: O objetivo deste trabalho foi avaliar o efeito do meloxicam sobre a taxa de concepção inicial (TCi), final (TCf) e perda gestacional (PG) de vacas Holandesas de alta produção submetidas à Transferência de Embrião (TE) Inseminação Artificial (IA) e Inseminação Artificial em Tempo Fixo (IATF). Na TE foram utilizadas, como receptoras de embrião, 492 vacas em lactação repetidoras de serviço. Na IA (n=312) e IATF (n=336) foram incluidas no estudo somente fêmeas recém paridas (com pelo menos 60 dias em lactação). Todas as fêmeas foram avaliadas e alocadas em um de dois grupos experimentais: Grupo Controle (GC) e Grupo Tratado (GT). O tratamento consistiu na administração i.m. de meloxicam injetável 2% (0,5mg/kg de peso) nos dias 7, 8 e 9 após a inovulação das receptoras de embrião, e nos dias 14, 15 e 16 da possível gestação das fêmeas submetidas a IA e IATF. Amostras de sangue foram colhidas nos D14 e D21 para posterior dosagem de progesterona (P4). O diagnóstico de gestação ocorreu aos 25-38 e 39-52 dias. O tratamento com o antiinflamatório não incrementou as TCi, TCf e tampouco diminuiu a PG em nenhuma das três biotecnologias. Contudo, observou-se que receptoras de embrião inovuladas com embriões congelados/descongelados do GT tiveram TCi e TCf menores que as do GC (GT= 25,8% v. GC=37,8%) .Não houve diferença na concentração sérica de progesterona de vacas do GC e do GT no D21. Contudo, houve efeito da estação do ano sobre as concentrações de P4 no D14 e D21 tanto na TE como na IA e IATF. Ainda, vacas gestantes apresentaram maiores concentrações de P4 que vacas não gestantes no D21. Conclui-se que o tratamento com meloxicam não incrementou as TCi, TCf, tampouco reduziu a PG de vacas Holandesas de alta produção
Abstract: The aim of this study was to evaluate the effect of meloxicam on initial conception rate, final conception rate and pregnancy loss of high-producing Holstein cows submitted to embryo transfer (ET), artificial insemination (AI) and timed artificial insemination (TAI). On ET, 492 repeat breeders in milk were used as recipients. On AI (n=312) and TAI (n=336) only freshly calved cows (with at least 60 days in milk) were included in the study. The animals were evaluated and allocated in one of two experimental groups: Control Group (CG) and Treated Group (TG). The treatment consisted on administration of meloxicam 2% i.m. (0.5mg/kg of weight) on days 7, 8 and 9 after inovulation of embryo recipients, and on days 14, 15 and 16 of the possible pregnancy of females submmited to AI and TAI. Blood samples were collected on D14 and D21 for progesterone assay. The diagnosis of pregnancy was done on days 25-38 and 39-52. The treatment with the antiinflamatory did not increase initial conception rates and final conception rates, nor decreased pregnancy loss of animals in all three biotechnologies. However, recipients of TG inovulated with frozen/thawed embryos had lesser initial and final conception rates than CG (TG= 25.8% v. CG=37.8%) There was no difference on progesterone serum concentration of cows from TG and CG on D21. However, there was a season effect on P4 concentrations on D14 and 21 for ET, AI and TAI. Pregnant cows had higher P4 concentrations than non-pregnant cows. In conclusion, the treatment with meloxicam did not increase initial and final conception rates, neither decreased pregnancy loss of high producing Holstein cows
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