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1
Wilson, Stacey J. "The effect of heat stress on ovarian function in dairy cattle /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9842573.
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Lekola, Khomotso Podile Molvia. "Improvement of cattle oocyte retrieval techniques and hormonal influence on in vitro embryonic development." Thesis, University of Limpopo, 2015. http://hdl.handle.net/10386/1546.
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Thesis (M. Sc. (Animal Production)) -- University of LimpopoThe objectives of this study were: 1) To determine the effect of oocyte retrieval techniques (slicing and aspiration) on the quality and quantity of cattle oocytes, 2) To evaluate the effect of different concentrations of hormones on the maturational rate of cattle oocytes selected by brilliant cresyl blue staining, 3) To evaluate fertilization rate and cleavage/embryonic development of oocytes with or without cumulus cells, and 4) To compare the effect of fresh and frozen thawed semen on the fertilization rate of cattle oocytes. In Experiment 1: oocytes were recovered from abattoir derived ovaries using slicing and aspiration. The recovered oocytes were exposed for 90 minutes to 26μM of brilliant cresyl blue (BCB) stain and classified according to the colour of their cytoplasm: BCB+ (oocytes with blue cytoplasm) and BCB- (unstained oocytes). There was no difference (P>0.05) in the quality of oocytes recovered using slicing (60.7 %) or aspiration (53.7 %) techniques. In experiment 2: The BCB selected and the non-selected immature oocytes were randomly allocated into medium 199 + 10 % fetal bovine serum (FBS) maturation media. The media was supplemented with three different concentrations of hormones as treatments (T). The T1 (0.5 μg/ml of follicle stimulating hormone (FSH), 5mg/ml of luteinizing hormone (LH) and 2 μg/ml of estradiol (E2) as the control group. Then, T2 (1 μg/ml of FSH, 6 mg/ml of LH and 2.5 μg/ml of E2) and T3 (1.5 μg/ml of FSH, 7 mg/ml of LH and 4.5 μg/ml of E2). Maturation rate of oocytes was determined by the protrusion of the first polar bodies 24 hours following in vitro maturation. Treatment 2 yielded higher (P<0.05) maturation rate for both BCB+ (65.6 %) and without BCB (60.3 %) oocytes with T1 giving lower (P<0.05) maturation rate for BCB+ (22 %) and without BCB (16 %) oocytes. However, BCB- oocytes had lower (P<0.05) polar body extrusion (3.03 %, 8.1 % and 2.2 %) for T1, T2 and T3, respectively. In Experiment 3: one group of the presumptive zygotes was denuded of cumulus cells and the other group was cultured with cumulus cells. The presumptive zygotes were in vitro cultured in SOF-BSA and changed to SOF-FBS after 48 hours. High fertilization/cleavage rate was observed in oocytes cultured with cumulus cells (29.0 %) compared to the denuded oocytes (20.0 %) for 2-4 cells stage. Day 7 blastocysts were more (P<0.05) on oocytes cultured with cumulus cells (32 %) compared to denuded oocytes (13 %). In experiment 4: The matured oocytes were fertilized using fresh and frozen thawed semen. The oocytes fertilized with frozen thawed semen obtained a better number of 2-4 cell cleavage (23 %) when compared to fresh semen (19 %). Oocytes that were fertilized with frozen thawed semen also obtained higher morula (13 %) and blastocyst (8 %) compared to fresh semen with morula (3.4 %) and blastocyst (2 %). In conclusion, immature oocytes that were exposed to BCB+ and cultured in M199 supplemented with 10 % FBS, 0.5 μg/ml of FSH, 5 mg/ml of LH and 2 μg/ml of E2 had a higher (P<0.05) number of matured oocytes (extrusion of first polar body) compared to those that were not exposed to BCB (no BCB). Oocytes that were cultured with cumulus cells yielded a higher (P<0.05) number of cleaved embryos compared to the denuded oocytes. Slicing yielded a higher (P<0.05) number of oocytes, however the quality of oocytes recovered was similar compared to those recovered by the aspiration technique (P>0.05). Oocytes fertilized with frozen thawed semen yielded higher (P<0.05) number of 2-4 cell, morula and blastocyst when compared with oocytes that were fertilized using fresh semen. Keywords: ovaries, oocytes, slicing, aspiration, COCs, BCB, polar body and cattle
3
Barkley, Nicole Marie Garverick Henry Allen. "Characterization of apoptosis in the developing bovine fetal ovary association with germ cell loss /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/6105.
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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 9, 2009) Thesis advisor: Dr. H. Allen Garverick. Vita. Includes bibliographical references.
4
Kolath, Sarah Jane. "Ovarian gene expression in heat-stressed dairy cattle /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1426077.
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Liu, Zhilin. "Gene expression profiling of bovine ovarian follicular selection." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4490.
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Thesis (Ph.D.)--University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pf file; the official abstract appears in the short.pf file (which also appears in the research.pf); a non-technical general description, or public abstract, appears in the public.pf file. Title from title screen of research.pf file (viewed on May 6, 2009) Vita. Includes bibliographical references.
6
Calder, Michele D. "Ovarian cysts in dairy cattle : importance of serum LH concentrations in maintenance of cysts and expression of mRNAs for steroidogenic enzymes and gonadotropin receptors /." free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9924869.
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Ribadu, Yusufu. "Ultrasonography and endocrinology of ovarian cysts in cattle." Thesis, University of Liverpool, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386799.
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Burke, Christopher R. "Regulation of Ovarian Follicular Development with Estradiol in Cattle." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1054666226.
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9
Wrathall, Julia H. M. "Inhibin and the regulation of ovarian function in cattle and sheep." Thesis, University of Reading, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304807.
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10
Taylor, Christopher C. "Ovarian activity in postpartum, early pregnant and norgestomet synchronized dairy cattle." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28994.
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Studies to monitor bovine ovarian function with regard to follicular growth and turnover, and corpus luteum (CL) growth and function, were carried out during three different reproductive states: the postpartum anestrus period, early pregnancy and during the artificial control of the estrous cycle with the synthetic progestin norgestomet. Ovarian function was monitored using a combination of ultrasound imaging and progesterone (P₄) profiling.
Growth of large antral follicles (> 10mm) was found to commence very early in the postpartum period and ovulation occurred as early as the first week postpartum. Short first postpartum estrous cycles (< 18 days) were observed in a minority of the animals studied (4/10) and the occurance of a short first cycle was not associated with an early ovulation following parturition. Growth of large antral follicles occurred in a wave-like pattern during the postpartum estrous cycles with most cycles being composed of two waves of growth, the second wave resulting in the growth of the ovulatory follicle.
A wave-like pattern of growth of large dominant follicles
was also seen through the first 60 days of pregnancy. There was no difference between pregnant and non pregnant cows in the size of the dominant follicle found on day 20. In
addition no effect of the CL could be found on the side on which the dominant follicle was found, it was as likely to be on the ipsilateral ovary to the CL as on the contra lateral.
The gonadotrophin ihibitor norgestomet did not effect follicular dynamics in the presence of the CL, however in the absence of a CL the dominant follicle present was maintained for the duration of the norgestomet treatment and then went on to ovulate upon norgestomet removal. In addition there was no new growth of antral follicles in the absence of a CL. Norgestomet did not effect the temporal relationship between the onset of standing estrus, the LH surge and ovulation.
The results of the three studies suggest that a wavelike
pattern of growth of large antral follicles is a characteristic
of the bovine ovary regardless of the reproductive state.Land and Food Systems, Faculty of
Graduate
11
Kayani, Amjad R. "Utility of in vitro models for investigating ovarian follicle function in cattle." Thesis, University of Reading, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.435687.
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Johnson, Cynthia Jeane. "Cystic ovarian disease in cattle on dairies in central and western Ohio ultrasonic, hormonal, histologic, and metabolic assessments /." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5num=osu1072713205.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xiv, 153 p. : ill. Advisor: Joseph S. Ottobre, Dept. of Animal Sciences. Includes bibliographical references (p. 138-153).
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Gregson, Emma. "Functional Competence of the First and Final Wave Dominant Ovarian Follicle in Cattle." Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.523070.
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Hampton, James Howard. "Luteinizing hormone modulation of bovine ovarian follicular growth, selection and pathology /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p3101022.
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Tauck, Shaun Austin. "The biostimulatory effect of bulls on the hypothalamic-pituitary-adrenal and ovarian axes and on temporal aspects of resumption of ovarian cycling activity in primiparous, postpartum, anestrous, suckled, beef cows." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/tauckTauckS1208.pdf.
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Exposing cows to bulls or excretory products of bulls stimulates resumption of ovarian cycling activity in postpartum, suckled, anestrous cows. This biostimulatory effect may be mediated by pheromones produced by bulls that stimulate physiological changes in the hypothalamic-pituitary-ovarian (HPO) and/or -adrenal (HPA) axes of cows. In Experiment 1, the hypothesis tested was that the biostimulatory effect of bulls is associated with adrenal regulation and/or function in anestrous cows. The biostimulatory effect of bulls was associated with mean concentrations of cortisol in postpartum cows. Experiment 2 was designed to determine if acute (5-h daily) bull exposure alters characteristics of patterns of cortisol and luteinizing hormone (LH) concentrations in postpartum, anestrous cows. Cows exposed acutely to bulls exhibited fewer pulses of cortisol and more frequent pulses of LH than cows exposed to steers. However, it was not known if these changes were related to resumption of ovarian cycling activity in postpartum, anestrous cows. Experiment 3 was designed to test the hypothesis that patterns of cortisol concentrations are altered by continuous, 24-h daily, bull exposure, before and after resumption of ovarian cycling activity in postpartum, anestrous cows. Continuous bull exposure decreased cortisol pulse frequency before cows resumed ovarian cycling activity. Experiment 4 tested the hypothesis that the overall shape of patterns of cortisol and/or LH concentrations may differ between cows exposed acutely to bulls or steers in Experiment 2. Cows exposed acutely to bulls had more uneven patterns of LH concentrations than cows exposed to steers and as patterns of cortisol concentrations became smoother, patterns of LH become more uneven in cows exposed acutely to bulls. In Experiment 5, the hypothesis tested was that interval to resumption of ovarian cycling activity may depend upon duration of daily bull exposure. Cows resumed ovarian cycling activity sooner as duration of daily bull exposure increased. In conclusion, as duration of daily bull exposure increases, the biostimulatory effect of bulls alters activity of the HPA axis and this change may facilitate or support the function of the HPO axis and accelerate resumption of ovarian cycling activity in primiparous, postpartum, suckled, anestrous cows.
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Tauck, Shaun Austin. "Factors associated with the biostimulatory effect of bulls on resumption of ovarian cycling activity and breeding performance of first-calf suckled beef cows." Thesis, Montana State University, 2005. http://etd.lib.montana.edu/etd/2005/tauck/TauckS0505.pdf.
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Stevens, Jeffrey David. "LHRH fusion protein vaccines in beef heifers and bovine ectopic ovarian xenografting." Online access for everyone, 2004. http://www.dissertations.wsu.edu/Dissertations/Fall2004/J%5FStevens%5F092204.pdf.
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Garbarino, Eduardo Jose. "Effect of lameness on ovarian activity in post-partum holstein cows." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0004822.
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Thesis (M.S.)--University of Florida, 2004.Typescript. Title from title page of source document. Document formatted into pages; contains 108 pages. Includes Vita. Includes bibliographical references.
19
Salfen, Brent Edward. "Effect of the dominant ovarian follicle on the establishment and regulation of postpartum estrous cycles in dairy and beef animals /." free to MU campus, to others for purchase, 2000. http://wwwlib.umi.com/cr/mo/fullcit?p9974683.
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Johnson, Cynthia J. "Cystic ovarian disease in cattle on dairies in central and western Ohio: ultrasonic, hormonal, histologic, and metabolic assessments." The Ohio State University, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=osu1072713205.
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Machado, Mariana Fernandes [UNESP]. "Expressão e função de membrso das subfamílias FGF-8 e FGF-9 em folículos antrais bovinos." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/102441.
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Fatores de crescimento fibroblástico (FGFs) regulam o desenvolvimento folicular e a maturação oocitária através de ligação aos seus receptores (FGFRs). Os RNAm que codificam o FGFR2c e o FGFR3c foram detectados em folículos antrais bovinos. Com o objetivo de identificar FGFs que poderiam regular a foliculogênese por meios desses, investigou-se os padrões de expressão do FGF16 e FGF20 em folículos antrais bovinos, bem como os níveis de RNAm desses FGFs e seus receptores (FGFR2c e FGFR3c) durante a maturação in vitro de complexos cumulus-oócito (COCs). Além disso, dados preliminares do nosso laboratório indicativos de que a expressão do FGF17 em oócitos é regulada ao longo da maturação oocitária motivaram a investigação da função dessa proteína na maturação de COCs in vitro. Sendo assim, avaliou-se o efeito do FGF17 na expansão do cumulus e no controle da transcrição de fatores EGF-like [ampiregulina (AREG), epiregulina (EREG) e betacelulina (BTC)] e outros genes reguladores da expansão [cicloxigenase 2 (COX2), hialurona sintase 2 (HAS 2), pentraxina 3 (PTX3), proteína indutora do fator de necrose tumoral 6 (TSG6)]. Os RNAm dos FGF16 e FGF20 e as respectivas proteínas foram detectados no ovário bovino. A abundância de RNAm de FGF16 e FGF20 foi maior em células da granulosa e da teca de folículos atrésicos comparados a folículos saudáveis ou transicionais. O tratamento com FSH diminuiu a abundância de RNAm para FGF16 e FGF20 e o IGF1 inibiu FGF16 em células da granulosa cultivadas in vitro. Ao longo da maturação a expressão do FGF16 e do FGF20 foi estável no oócito, enquanto que a expressão dos receptores FGFR2c e FGFR3c foi estimulada nas células do cumulus pelo FSH. A proteína FGF16 foi localizada no oócito, células do cumulus e da teca e o FGF20 em oócitos, células do cumulus, da granulosa e da teca. O FGF17 aumentou a proporção...
Fibroblast growth factors (FGFs) regulate follicular development and oocyte maturation. Messenger RNA encoding receptors FGFR3c and FGFR2c have been detected in bovine antral follicles. Aiming to identify FGFs that can potentially regulate folliculogenesis through these receptors, the expression patterns of FGF16 and FGF20 were assessed in bovine antral follicles. Messenger RNA expression of these FGFs and their receptors (FGFR2c and FGFR3c) was also assessed in oocytes and cumulus cells, respectively, during in vitro maturation. In addition, previous data suggesting that FGF17 mRNA expression is regulated in the oocyte led us to investigate the effects of FGF17 on cumulus expansion and on the expression of EGF-like factors [amphiregulin (AREG), epiregulin (EREG) and betacelullin (BTC)] and other genes that regulate expansion [cyclooxygenase 2 (COX2), hyaluronan synthase 2 (HAS 2), pentraxin 3 (PTX3), protein-inducing tumor necrosis factor 6 (TSG6)]. FGF16 and FGF20 mRNA and proteins were detected in the bovine ovary. Messenger RNA abundance of FGF16 and FGF20 was higher in granulosa and theca cells from atretic follicles compared with healthy or transitional follicles. Treatment with FSH decreased mRNA expression of FGF16 and FGF20 and IGF1 inhibited FGF16 mRNA abundance in cultured granulosa cells. During maturation, mRNA expression of FGF16 and FGF20 was stable in the oocyte, while FGFR2c and FGFR3c were stimulated in cumulus cells by FSH. FGF16 protein was localized to the oocyte, cumulus and theca cells, and FGF20 was detected in the oocyte, cumulus, granulosa and theca cells. Supplementation of maturation medium with FGF17 increased the proportion of fully expanded COCs, but did not alter mRNA expression of COX2, HAS2, PTX3, TSG6, AREG, EREG and BTC in cumulus cells during in vitro maturation. In conclusion, FGF17 enhances bovine cumulus expansion... (Complete abstract click electronic access below)
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Machado, Mariana Fernandes. "Expressão e função de membrso das subfamílias FGF-8 e FGF-9 em folículos antrais bovinos /." Botucatu : [s.n.], 2012. http://hdl.handle.net/11449/102441.
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Orientador: José Buratini JuniorBanca: Fabíola Freitas de Paula Lopes
Banca: Marcelo Nogueira
Banca: Cláudia Lima Verde Leal
Banca: João Carlos Pinheiro Ferreira
Resumo: Fatores de crescimento fibroblástico (FGFs) regulam o desenvolvimento folicular e a maturação oocitária através de ligação aos seus receptores (FGFRs). Os RNAm que codificam o FGFR2c e o FGFR3c foram detectados em folículos antrais bovinos. Com o objetivo de identificar FGFs que poderiam regular a foliculogênese por meios desses, investigou-se os padrões de expressão do FGF16 e FGF20 em folículos antrais bovinos, bem como os níveis de RNAm desses FGFs e seus receptores (FGFR2c e FGFR3c) durante a maturação in vitro de complexos cumulus-oócito (COCs). Além disso, dados preliminares do nosso laboratório indicativos de que a expressão do FGF17 em oócitos é regulada ao longo da maturação oocitária motivaram a investigação da função dessa proteína na maturação de COCs in vitro. Sendo assim, avaliou-se o efeito do FGF17 na expansão do cumulus e no controle da transcrição de fatores EGF-like [ampiregulina (AREG), epiregulina (EREG) e betacelulina (BTC)] e outros genes reguladores da expansão [cicloxigenase 2 (COX2), hialurona sintase 2 (HAS 2), pentraxina 3 (PTX3), proteína indutora do fator de necrose tumoral 6 (TSG6)]. Os RNAm dos FGF16 e FGF20 e as respectivas proteínas foram detectados no ovário bovino. A abundância de RNAm de FGF16 e FGF20 foi maior em células da granulosa e da teca de folículos atrésicos comparados a folículos saudáveis ou transicionais. O tratamento com FSH diminuiu a abundância de RNAm para FGF16 e FGF20 e o IGF1 inibiu FGF16 em células da granulosa cultivadas in vitro. Ao longo da maturação a expressão do FGF16 e do FGF20 foi estável no oócito, enquanto que a expressão dos receptores FGFR2c e FGFR3c foi estimulada nas células do cumulus pelo FSH. A proteína FGF16 foi localizada no oócito, células do cumulus e da teca e o FGF20 em oócitos, células do cumulus, da granulosa e da teca. O FGF17 aumentou a proporção... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Fibroblast growth factors (FGFs) regulate follicular development and oocyte maturation. Messenger RNA encoding receptors FGFR3c and FGFR2c have been detected in bovine antral follicles. Aiming to identify FGFs that can potentially regulate folliculogenesis through these receptors, the expression patterns of FGF16 and FGF20 were assessed in bovine antral follicles. Messenger RNA expression of these FGFs and their receptors (FGFR2c and FGFR3c) was also assessed in oocytes and cumulus cells, respectively, during in vitro maturation. In addition, previous data suggesting that FGF17 mRNA expression is regulated in the oocyte led us to investigate the effects of FGF17 on cumulus expansion and on the expression of EGF-like factors [amphiregulin (AREG), epiregulin (EREG) and betacelullin (BTC)] and other genes that regulate expansion [cyclooxygenase 2 (COX2), hyaluronan synthase 2 (HAS 2), pentraxin 3 (PTX3), protein-inducing tumor necrosis factor 6 (TSG6)]. FGF16 and FGF20 mRNA and proteins were detected in the bovine ovary. Messenger RNA abundance of FGF16 and FGF20 was higher in granulosa and theca cells from atretic follicles compared with healthy or transitional follicles. Treatment with FSH decreased mRNA expression of FGF16 and FGF20 and IGF1 inhibited FGF16 mRNA abundance in cultured granulosa cells. During maturation, mRNA expression of FGF16 and FGF20 was stable in the oocyte, while FGFR2c and FGFR3c were stimulated in cumulus cells by FSH. FGF16 protein was localized to the oocyte, cumulus and theca cells, and FGF20 was detected in the oocyte, cumulus, granulosa and theca cells. Supplementation of maturation medium with FGF17 increased the proportion of fully expanded COCs, but did not alter mRNA expression of COX2, HAS2, PTX3, TSG6, AREG, EREG and BTC in cumulus cells during in vitro maturation. In conclusion, FGF17 enhances bovine cumulus expansion... (Complete abstract click electronic access below)
Doutor
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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 ñ 2.9, 99 ñ 2.8, and 29 ñ 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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Hendricks, Katherine Elizabeth May. "Reproductive strategies in the postpartum dairy cow with reference to anovulation and postpartum uterine health." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0007013.
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Thesis (M.S.)--University of Florida, 2004.Typescript. Title from title page of source document. Document formatted into pages; contains 176 pages. Includes Vita. Includes bibliographical references.
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Silvestre, Flávio Teixeira. "Reproductive, ovarian, and uterine responses to a GnRH-agonist (Deslorelin) implant during and after the postpartum summer heat-stress period in dairy cattle." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0002839.
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Doyle, Lynsey Kerr. "Role of vascular endothelial growth factor (VEGF) in granulosa cell function : involvement of heterotrimeric G-protein signalling pathways." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/4297.
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Vascular Endothelial Growth Factor (VEGF) has been shown to be an absolute requirement for ovarian follicle development. Although VEGF is commonly regarded primarily as an angiogenic factor, granulosa cells are a major site of VEGF synthesis in the follicle and they express VEGF receptors (VEGFR1 and VEGFR2). Further, the development of the dominant follicle is characterised by a substantial increase in granulosa cell expression of VEGF and its receptors. In spite of this, potential non-angiogenic effects of VEGF in these follicles have not been elucidated. The objective of the three studies described in this thesis was to use an in vitro bovine granulosa cell model to investigate the roles of VEGF during development of the dominant follicle. In addition, in light of evidence in other cell types, potential interactions between VEGF signalling and heterotrimeric protein signalling in these follicles were also investigated. In the first study, granulosa cells were obtained from healthy follicles with diameters of 4 to 8 mm (corresponding to just before the selection of a dominant follicle during a follicular wave) or 9 to 14 mm (encompassing all developmental stages of a dominant follicle) and exposed to a range of VEGF concentrations (1 to 100 ng/ml) encompassing concentrations found naturally in bovine dominant follicles. VEGF at 1 ng/ml, but not at higher concentrations (P > 0.1), induced significant proliferation of bovine granulosa cells from 4 to 8 mm follicles (P = 0.024) and increased the proliferative response of these cells to FSH (P = 0.045). VEGF also induced a dose-dependent increase in ERK1/2 activation by granulosa cells from 4 to 8 mm follicles (P < 0.03) but did not have any effect on expression of the steroidogenic enzyme, CYP11A1, by these cells (P > 0.1). VEGF, at a dose of 1 ng/ml (P = 0.003), but not at higher doses (P > 0.1), induced an increase in COX-2 expression by granulosa cells from 9 to 14 mm follicles. In addition, LH stimulation of both ERK phosphorylation (P < 0.05) and COX-2 expression (P < 0.05) in granulosa cells from 9 to 14 mm follicles were prevented (P > 0.1) by specific inhibition of VEGFR2, indicating that VEGF may mediate COX-2 responses to LH in these cells. The second study sought to examine the expression of heterotrimeric G-protein á subunits and PLCâ isoforms by real-time PCR and westen blotting in bovine granulosa cells throughout follicle development to identify specific molecular components of heterotrimeric G-protein pathways that may functionally interact with intracellular VEGF signals. Results showed that GNAS, GNA11 and GNAI2 were all expressed at significantly (P < 0.05) higher levels in granulosa cells of pre-ovulatorysize follicles (10.0 to 13.9 mm) than in cells from smaller follicles (2.0 to 5.9 mm and 6.0 to 9.9 mm). In addition, all PLCB isoforms except PLCB2 were expressed in bovine granulosa cells with PLCB3 being more abundant than PLCB1 and -4. Levels of PLCB3 in granulosa cells from pre-ovulatory-size follicles were much higher (>16-fold; P < 0.005) than in smaller follicles. Immunocytochemical analysis revealed that PLCB3 was located primarily in the cytoplasm, whereas PLCB1 was distributed primarily in the nucleus. These results identified Gs, Gq/11, Gi2 and PLCâ3 as candidates for cross-talk between VEGF and heterotrimeric G-protein signalling during the development of the dominant follicle. The potential involvement of these molecules on VEGF-induced responses in granulosa cells from 9-14 mm follicles was investigated in the third study by determining the effects of specific inhibitors of Gi (pertussis toxin, PTX) or Gq/11 (YM-25489) or PLCB3 siRNAs on VEGF-induced p-ERK. Results showed a 2.3 fold mean increase in p-ERK in response to VEGF in the absence of G protein inhibitors (P < 0.0001) but a VEGF response that was completely or partially abolished, respectively, in the presence of PTX (P > 0.8) or YM-25489 (1.6-fold mean increase relative to untreated controls; P = 0.039). LH induced a 1.6 fold increase in p-ERK1/2 (P < 0.02) and this response was prevented by pre-incubation with PTX (P > 0.4) or YM-25489 (P > 0.5). In contrast, similar EGF-induced phosphorylation of ERK (about 5-fold relative to controls) occurred in the absence (P < 0.003) or presence of PTX (P < 0.003) or YM-25489 (P < 0.003). Transfection of granulosa cells with 3 siRNAs targeting PLCB3 that had been previously validated by western blotting and immunocytochemistry had no effect (P = > 0.7) on phosphorylation of ERK in response to VEGF, LH or EGF in granulosa cells. In conclusion, taken together, these results suggest novel roles of VEGF in stimulating granulosa cell proliferation and expression of COX-2 in bovine dominant follicles and implicate VEGF in synergising and/or mediating the effects of gonadotrophins in these cells. In addition, these results indicate a requirement for Gi2 and Gq/11 in VEGF activation of ERK1/2 and induction of the above responses in granulosa cells.
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Dawuda, Philip Makama. "The effects and mechanisms of action of nutritional changes, differential suckling intensities and time postpartum in causing ovulation failure and ovarian acyclicity in beef cattle." Thesis, University of Aberdeen, 1995. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU079011.
Full textAbstract:
Undernutrition and suckling effects on reproductive performance in cattle were investigated. It was therefore, the aim of this study to (1) evaluate reproductive parameters that were to be used in assessing reproductive function in heifers and postpartum cows; (2) to assess the effect of undernutrition and realimentation on ovulation and ovarian cyclicity in beef heifers; (3) to assess the effect of suckling intensity alone or in combination with undernutrition and the time postpartum in delaying reinitiation of ovulation in lactating beef cows. The results of this experiment showed that following the reduction in feed intake to half maintenance requirements there were four different types of changes in ovarian cyclicity recorded in the ten heifers. Group 1. Three heifers (No.1, 2 & 3) became acyclic without going through an oestrous cycle. Group 2. Four heifers (No. 4, 5, 6 & 7) went through one normal oestrous cycle each before becoming acyclic. Group 3. One heifer (No. 8) underwent two normal oestrous cycles before becoming acyclic. Group 4. Two heifers (No 9 & 10) continued to cycle without becoming acyclic. One of these two heifers (No. 9) had four short oestrous cycles of 8, 9, 11 and 11 days while No. 10 had three short oestrous cycles of 10, 12 and 12 days. During nutritional acyclicity there were no increases in LH concentration over the basal concentration following naloxone challenge irrespective of the dose used. During undernutrition, one heifer (No. 8) failed to exhibit an oestradiol-induced LH surge while the two heifers (NO. 9 & 10) exhibited a oestradiol-induced LH surge. There were no LH surges following PRID withdrawal in nutritionally acyclic heifers.
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Awasthi, Hitesh. "Excessive lipid contents in immature oocytes from repeat breeder dairy heifers /." Uppsala : Dept. of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/10463781.pdf.
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Corte, Júnior Anivaldo Olivio. "Variação do ciclo estral de novilhas Bos taurus indicus (Nelore) em diferentes estações do ano /." Araçatuba : [s.n.], 2009. http://hdl.handle.net/11449/94701.
Full textAbstract:
Orientador: Guilherme de Paula NogueiraBanca: José Luis Moraes Vasconcelos
Banca: Ciro Moraes Barros
Resumo: Seis novilhas Nelore tiveram seus ciclos estrais acompanhados durante diferentes estações do ano (outono n=11; inverno n=8; primavera n=9; verão n=9) com exames ultrassonográficos diários para contar e mensurar folículos ≥3mm. Amostras de sangue foram colhidas a cada 12h para hormônio luteinizante (LH) e progesterona (P4), e a cada 3h do estro até a ovulação para caracterizar o pico de LH. Cinco novilhas ovariectomizadas receberam 17β-estradiol (2μg/kg/p.v.) em cada estação, e amostras de sangue foram colhidas depois disso a cada 3h para quantificação de LH. A diferença percentual mensal ( %) do peso não variou entre as estações. A concentração média de P4 no ciclo estral foi maior (p=0,001) e o número de folículos menor (p=0,001) durante o outono (2,5±0,2ng/mL; 7,8±0,1) e verão (2,9±0,3ng/mL; 6,8±0,2) comparado com o inverno (1,4±0,2ng/mL; 9,6±0,3) e primavera (1,6±0,2ng/mL; 9,7±0,3). Durante o inverno houve mais ciclos estrais com três (5 de 8) e durante o verão somente ciclos com duas ondas foliculares (p=0,009). Como a secreção de LH não variou, apesar da variação sazonal na concentração de P4, e como houve correlação negativa entre os valores máximos de P4 e a variação percentual do fotoperíodo (p=0,0056; r = -0,4465), uma variação sazonal na sensibilidade das células luteínicas ao LH precisa ser avaliada. Nas novilhas ovariectomizadas, a concentração circanual de LH sem o estímulo de estradiol foi significante (p=0,0214). A resposta de LH ao tratamento de estradiol foi menor no verão (0,8±0,2ng/mL vs 1,3±0,5ng/mL). Nós supomos que existe variação sazonal na sensibilidade hipotalâmica ao estradiol.
Abstract: Six Nelore heifers had their estrous cycle followed during different seasons of the year (autumn n=11; winter n=8; spring n=9 and summer n=9) with daily ultrasonographic exams to count and measure follicles ≥3mm. Blood was collected every 12h for luteinizing hormone (LH) and progesterone (P4), and every 3h from estrus until ovulation to characterize the LH peak. Five ovariectomized heifers were injected with 17β-estradiol (2μg/kg/LW) every season and blood samples were collected thereafter at 3h intervals for LH quantification. The monthly body weight percentile difference ( %) did not vary between seasons. Average P4 concentration for the cycle was higher (p=0.001) and follicle number lower during autumn (2.5±.2ng/ml; 7.8±.1) and summer (2.9±.3ng/ml; 6.8±.2) (p=0.001) compared to winter (1.4±.2ng/ml; 9.6±.3) and spring (1.6±.2ng/ml; 9.7±.3). During winter there were more estrous cycles with three follicle waves (5 out of 8) and during summer only cycles with two follicular waves (p=0.009). As LH secretion did not vary despite seasonal variation in P4 concentration and as there was a negative correlation between higher P4 values and daily percentile variation of photoperiod ( %, p=0.0056; r= -0.4465), a seasonal variation in luteal cell sensitivity to LH needs to be evaluated. In the ovariectomized Nelore heifers, the LH circanual concentration without estradiol stimulus was significant (p=0.0214). The LH response to estradiol treatment was lower in summer (0.8±.2ng/ml vs 1.3±.5ng/ml). We hypothesize there exists seasonal variation in hypothalamic sensitivity to estradiol.
Mestre
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Corte, Júnior Anivaldo Olivio [UNESP]. "Variação do ciclo estral de novilhas Bos taurus indicus (Nelore) em diferentes estações do ano." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/94701.
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Seis novilhas Nelore tiveram seus ciclos estrais acompanhados durante diferentes estações do ano (outono n=11; inverno n=8; primavera n=9; verão n=9) com exames ultrassonográficos diários para contar e mensurar folículos ≥3mm. Amostras de sangue foram colhidas a cada 12h para hormônio luteinizante (LH) e progesterona (P4), e a cada 3h do estro até a ovulação para caracterizar o pico de LH. Cinco novilhas ovariectomizadas receberam 17β-estradiol (2μg/kg/p.v.) em cada estação, e amostras de sangue foram colhidas depois disso a cada 3h para quantificação de LH. A diferença percentual mensal ( %) do peso não variou entre as estações. A concentração média de P4 no ciclo estral foi maior (p=0,001) e o número de folículos menor (p=0,001) durante o outono (2,5±0,2ng/mL; 7,8±0,1) e verão (2,9±0,3ng/mL; 6,8±0,2) comparado com o inverno (1,4±0,2ng/mL; 9,6±0,3) e primavera (1,6±0,2ng/mL; 9,7±0,3). Durante o inverno houve mais ciclos estrais com três (5 de 8) e durante o verão somente ciclos com duas ondas foliculares (p=0,009). Como a secreção de LH não variou, apesar da variação sazonal na concentração de P4, e como houve correlação negativa entre os valores máximos de P4 e a variação percentual do fotoperíodo (p=0,0056; r = -0,4465), uma variação sazonal na sensibilidade das células luteínicas ao LH precisa ser avaliada. Nas novilhas ovariectomizadas, a concentração circanual de LH sem o estímulo de estradiol foi significante (p=0,0214). A resposta de LH ao tratamento de estradiol foi menor no verão (0,8±0,2ng/mL vs 1,3±0,5ng/mL). Nós supomos que existe variação sazonal na sensibilidade hipotalâmica ao estradiol.
Six Nelore heifers had their estrous cycle followed during different seasons of the year (autumn n=11; winter n=8; spring n=9 and summer n=9) with daily ultrasonographic exams to count and measure follicles ≥3mm. Blood was collected every 12h for luteinizing hormone (LH) and progesterone (P4), and every 3h from estrus until ovulation to characterize the LH peak. Five ovariectomized heifers were injected with 17β-estradiol (2μg/kg/LW) every season and blood samples were collected thereafter at 3h intervals for LH quantification. The monthly body weight percentile difference ( %) did not vary between seasons. Average P4 concentration for the cycle was higher (p=0.001) and follicle number lower during autumn (2.5±.2ng/ml; 7.8±.1) and summer (2.9±.3ng/ml; 6.8±.2) (p=0.001) compared to winter (1.4±.2ng/ml; 9.6±.3) and spring (1.6±.2ng/ml; 9.7±.3). During winter there were more estrous cycles with three follicle waves (5 out of 8) and during summer only cycles with two follicular waves (p=0.009). As LH secretion did not vary despite seasonal variation in P4 concentration and as there was a negative correlation between higher P4 values and daily percentile variation of photoperiod ( %, p=0.0056; r= -0.4465), a seasonal variation in luteal cell sensitivity to LH needs to be evaluated. In the ovariectomized Nelore heifers, the LH circanual concentration without estradiol stimulus was significant (p=0.0214). The LH response to estradiol treatment was lower in summer (0.8±.2ng/ml vs 1.3±.5ng/ml). We hypothesize there exists seasonal variation in hypothalamic sensitivity to estradiol.
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Manikkam, Mohan. "Atresia of the dominant ovarian follicle in cattle." Thesis, 1996. http://hdl.handle.net/2429/4793.
Full textAbstract:
During each bovine estrous cycle, two to three dominant follicles (DFs) develop. The DF
that develops at the time of corpus luteum (CL) regression ovulates. The first or second DF
reaches an ovulatory size, and is capable of ovulation during the luteal phase, but undergoes
morphological and functional atresia, probably due to a lack of high frequency luteinizing
hormone (LH) pulses which are regulated by high plasma progesterone (P₄) concentrations. The
focus of this thesis was to further investigate some of the causes and mechanisms of atresia of
the DF in cattle. A Norgestomet-maintained proestrus DF was chosen as an experimental model
to study atresia. It was possible to monitor this DF daily, through ultrasonography in a noninvasive
manner, without interference from other follicles. In heifers, P₄ , estradiol-17β (E₂) and
testosterone (T) when administered, caused regression of the DF, which was associated with a
reduction in systemic LH. The role of gonadotropins in the prevention of atresia of the DF was
examined by their deprivation, using bovine follicular fluid (BFF) and luteinizing hormone
releasing hormone antagonist (LHRHa). Both BFF and LHRHa caused regression of the DF, but
there was no FSH suppression by BFF; L H was significantly reduced by LHRHa treatment. The
role of FSH on the maintenance and ovulation of the DF was studied using BFF. The DF
regressed when BFF was given during maintenance phase, although there was no decrease in
FSH. Regression of the DF occurred in one subgroup during the ovulatory phase, and in the
other subgroup ovulation of the DF ensued. BFF injections abolished FSH and L H surges after
implant withdrawal. The mechanism of atresia of the DF was investigated in cows after P₄
treatment. The DF showed a decline in insulin-like growth factors-I and -II (IGF-I and II),
increase in low molecular weight IGF-binding proteins on ligand blots, a drastic reduction in
aromatase activity (AA), reduced E₂ content and increased apoptotic index. High concentrations
of steroids and(or) low concentrations of gonadotropins cause atresia of the DF, and the mechanism of P₄-induced atresia of the DF involves changes in IGF system, and a reduction
AA.
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Filho, Roberto Sartori. "Ovarian function, circulating steroids, and early embryonic development in dairy cattle." 2002. http://www.library.wisc.edu/databases/connect/dissertations.html.
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難波, 陽介, and Yousuke Naniwa. "Roles of hypothalamic kisspeptin in the control of ovarian functions in cattle." Thesis, 2014. http://hdl.handle.net/2237/20257.
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Adams, Gregg Patrick. "Ovarian function in llamas and cattle factors affecting follicular growth and emergence of follicular waves /." 1991. http://catalog.hathitrust.org/api/volumes/oclc/24563016.html.
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Thesis (Ph. D.)--University of Wisconsin--Madison, 1991.Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Chang, Chih-Chung, and 張智重. "Reduce Calving Intervals and Increase Production Life of Dairy Cattle through Endocrine Regulating of the Ovarian Function." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/17436915568679873798.
Full textAbstract:
碩士東海大學
畜產與生物科技學系
95
Reduce calving intervals and increase production life of dairy cattle through endocrine regulating of the ovarian function Reproductive management is very important for the dairy farm business. Effective management can hasten the recovery of postpartum ovarian function and improve the profit in dairy business. The purpose of this study was to investigate the relationship among various postpartum production traits , and to regulate the ovarian function to reduce the calving interval by using exogeneous hormone, hence to increase the lifespan of dairy cattle. Experiment 1 was conducted to observe the relationship among various blood constituents and production profiles. From calving to 45 days postpartum, five primiparous and four multiparous lactating dairy cows were used to measure body condition score(BCS)、dry matter intake(DMI)、and BW on a weekly basis；Milk were collected twice a week and milk constituents were analyzed accordingly；Blood were collected twice a week and serum were harvested for progesterone(P4)、glucose、insulin、and cholesterol analysis. The results showed that DMI、energy balance(EB)、milk yield(MY)、serum glucose、insulin、and cholesterol were starting to increase from week2 or week3 postpartum. BW was decreased after calving until week 4 postpartum. And then the lost BW was gradually recovered until week 7 postpartum. BCS was decreased from calving to week 7 postpartum. Experiment 2 was conducted to study the effects of various systematic breeding programs on reproductive performance of postpartum dairy cattle. The Ovsynch treatment group (n=11) received an injection (100μg) of GnRH at a random stage of estrus cycle , followed 7days later by an injection of 25 mg PGF2α and a second injection of GnRH (100μg) 2 days later .Cows were inseminated at a fix time 24h after final GnRH of Ovsynch. Pregnancy diagnosis was performed 35d later by palpation per rectum of uterine contents. The Presynch treatment group(n=10) started at d24 postpartum, and two PGF2α at a 14 d interval were used to synchronize the estrus , then the Ovsynch program would be followed 12 days later. The initial step of the Resynch program(n=10) was identical to the Presynch program. After TAI, the CIDR driver was inserted and a o.6mg E2 injection was performed 13 days later. The CIDR driver was removed 7 days later and a second E2(0.6mg) injection was performed 24 hours later preparing to detect estrus and AI in 24 hours. Presynch and Resynch groups has a better synchronization rate (P<0.05) than the Ovsynch group. Presynch protocol has higher incidence of ovulation (90% vs. 45.5%, P<0.05)、better conception rate (50% vs. 9.1%, P<0.05), and need less service per conception than Ovsynch treated cows. In conclusion, dairy cows after calving that increase DMI can decrease negative energy balance and resumption of ovarian cyclicity postpartum. And presynchronization before treated cows with Ovsynch protocol has the potential to enhance reproductive efficiency of dairy cattle. Key word：dairy cattle、reproductive efficiency、synchronization、Ovsynch、Presynch、Resynch
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"Development of a non-steroidal aromatase inhibitor-based protocol for the control of ovarian function using a bovine model." Thesis, 2013. http://hdl.handle.net/10388/ETD-2013-06-1065.
Full textAbstract:
Five studies were designed to characterize the effects of a non-steroidal aromatase inhibitor, letrozole, on ovarian function in cattle. The general hypothesis was that non-steroidal aromatase inhibitors have potential as a steroid-free option for the control of ovarian function for the purposes of fixed-time artificial insemination and embryo production. The specific objectives were to determine the effect of route and vehicle, type of aromatase inhibitor, and duration of aromatase inhibitor treatment (short vs prolonged) on ovarian follicles in cattle, and to test the efficacy of an aromatase inhibitor-based protocol to synchronize ovulation in cattle. In the first experiment, heifers were treated with letrozole intravenously (n=10) or intramuscularly (n=10) or allocated in iv and im control groups (n=5/group). During the second experiment, heifers were divided randomly into two groups (n=15/group) and an intravaginal device containing 1 g of letrozole or a blank device (control) was inserted. The third experiment was designed with the goal of formulating and testing an intravaginal device that provides biologically active circulating concentrations of an aromatase inhibitor for a minimum of 4 days. The biological significance of the pharmacokinetic differences between the letrozole intravaginal devices resulting from the third study was evaluated during the fourth study. A final study was designed to determine the effect of stage of the estrous cycle on the proportion of animals that ovulated and the synchrony of ovulation of heifers treated with an aromatase inhibitor-based ovulation-synchronization protocol and to determine subsequent pregnancy outcomes. In all the studies, the effects of aromatase inhibitor on ovarian function were assessed by transrectal ultrasound examination of the ovaries, and blood samples were collected for hormone concentration determination. Results demonstrated that route of administration, or more precisely, the nature of
iii
the vehicle used for the administration of letrozole (intravenous, intramuscular depot, short release intravaginal or prolonged release intravaginal) has an impact on the effects of letrozole on hormonal profiles and ovarian dynamics. The intramuscular route appeared to provide a prolonged release of letrozole from the injection site which had a marked effect on estradiol production, dominant follicle lifespan, and CL form and function. Letrozole treatment during the ovulatory follicle wave by means of a gel-based intravaginal releasing device during the second study resulted in more rapidly growing dominant follicles and larger ovulatory follicles, delayed ovulation (by 24 h) of a single follicle and formation of a CL that secreted higher levels of progesterone. A wax-based vehicle allowed for a steady and continuous delivery of the active compound over the treatment period. During the third study, the addition of a letrozole-containing gel coating increased the rate of initial absorption and hastened the increase on plasma concentrations of the active ingredient, while the letrozole-containing wax-based vehicle prolonged drug-delivery from the intravaginal device. When tested in vivo during the fourth study, we confirmed that letrozole-impregnated intravaginal devices formulated with a wax base plus a gel coat vehicle was most suitable for the application of a letrozole-based protocol for the synchronization of ovulation in cattle, since it effectively delivered elevated concentrations of letrozole, and reduced estradiol production resulting in increased follicular growth and lifespan, without adversely affecting progesterone production. The application of a letrozole-impregnated intravaginal device for 4 days, combined with PGF treatment at device removal and GnRH 24 h post-device removal increased the percentage of ovulations and synchrony of ovulation in cattle, regardless the stage of the estrous cycle at initiation of treatment. As observed in previous studies, the effects observed could be associated with an increase in circulating LH
iv
concentrations. However, the effects of treatment on gonadotropin concentrations are inconclusive, possibly due to inadequate sampling frequency. The impact of letrozole treatment of oocyte fertility remains unknown. The results of the five experiments support our general hypothesis that non-steroidal aromatase inhibitors have potential as a steroid-free option for the control of ovarian function in cattle. However, further research is needed in order to elucidate the effects of letrozole treatment during the proestrous on oocyte competence and fertility of the resulting ovulations in cattle.
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Aali, Muhammad. "Ovarian follicular dynamics, LH profiles, corpus luteum function and pregnancy following two ovulation synchronization/timed artificial insemination protocols in cattle." Thesis, 2003. http://hdl.handle.net/2429/15011.
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The reduced fertility following earlier estrus synchronization protocols made it necessary to develop new protocols based on our understanding of ovarian follicular dynamics and corpus luteum (CL) function in cattle. "Ovsynch" and "CIDR" are emerging protocols for ovulation synchronization that would facilitate artificial insemination at a fixed time (TAI) without estrus detection. Unfortunately, the limited and available literature on Ovsynch and CIDR treatment protocols focuses mainly on ovarian follicular dynamics during treatment and ovulation synchronization success. Therefore, the objectives of this study were to compare L H profiles, follicular dynamics, CL function and pregnancy rates (PR), following treatment with Ovsynch and CIDR ovulation synchronization/TAI protocols. In the first experiment, ultrasonography was performed throughout the treatment protocols and following ovulation for one complete cycle to monitor ovarian follicular and CL dynamics. Serial blood samples were taken to determine the L H profile and progesterone (P₄) concentrations throughout the treatment protocols and for one complete cycle following ovulation. Prolonged duration and larger diameter of the ovulatory follicle in the Ovsynch compared to CIDR protocol did not affect post synchronization LH profiles, follicular dynamics and P₄ concentrations, which were similar between Ovsynch and CIDR ovulation synchronization protocols. In experiment 2, CL's formed after Ovsynch and CIDR ovulation synchronization protocols were incubated with four different hormone treatments; LH, PGF[sub 2α] LH + PGF[sub 2α], and control (no treatment) to determine in vitro P₄ secretion. Corpora lutea formed after Ovsynch and CIDR ovulation synchronization protocols yielded similar in vitro P₄ concentrations at different stages of the synchronized cycle. The response to LH, PGF[sub 2α], and LH + PGF[sub 2α] was also not different between the two ovulation synchronization protocols. In experiment 3, the focus was to compare in vivo P₄ profiles and PR in lactating dairy cows following treatment with the Ovsynch and CLDR ovulation synchronization/TAI protocols. In vivo P₄ production and PR were similar between the Ovsynch and CIDR treatment protocols. Similar post synchronization LH profiles, follicular dynamics, P₄ profiles and PR following Ovsynch and CIDR ovulation synchronization protocols suggest that both protocols can be equally effective in synchronization of ovulation, elimination of estrus detection and enhancement of pregnancy in heifers as well as in cows. However, based on frequency of handling, cost, and industry approval, this study favors the use of the Ovsynch over the CIDR for ovulation synchronization in cows and heifers.
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"VITRIFICATION AND CHORIOALLANTOIC MEMBRANE (CAM) CULTURE OF BOVINE OVARIAN TISSUE." Thesis, 2015. http://hdl.handle.net/10388/ETD-2015-05-2051.
Full textAbstract:
The overall objectives of this thesis were to develop a short-term culture system and to examine the effects of vitrification and short-term culture on the viability of fresh and vitrified bovine ovarian tissue and the follicles within.
The first objective was to compare the health and development of preantral follicles in bovine ovarian tissue, as well as the neovascularization of these tissues, subjected to avian chorioallantoic membrane (CAM) culture with the traditional in vitro culture system. We hypothesized that the chorioallantoic membrane (CAM) of the chicken embryo is a
more suitable culture system than traditional in vitro culture. Bovine ovaries were retrieved from a local abattoir and cortical pieces (1-2mm3) were randomly assigned to one of the following groups; control (fixed immediately), CAM or in in vitro culture. Ovarian tissue fragments from both groups were removed on D1, D3 and D5 of culture, fixed, sectioned (5μm) and stained with H&E. The numbers of healthy and degenerated follicles, primordial and activated preantral (primary and secondary), and the number of infiltrated bovine and avian blood vessels were determined using standard stereological procedures. All grafts placed on the traumatized CAM demonstrated increased neovascularization over time. The healthy primordial follicle density decreased over time concomitant with an increase in degenerated (primordial and activated preantral) follicles in both treatment groups. Healthy activated preantral follicle density did not differ between the two culture systems at a given time. In CAM group, blood vessel density increased over time (p = 0.015).
The second objective of this thesis was to develop a suitable vitrification protocol for bovine ovarian tissue. The viability of bovine ovarian tissue vitrified using two non-permeating cryoprotectants (sucrose and trehalose) and two cryodevices (cryotop and cryovial) was assessed. We hypothesized that during vitrification the higher cooling rate on the cryotop (open vitrification method) will yield better post-thaw viability of bovine ovarian tissue as compared to the cryovial (closed vitrification method). We also hypothesized that trehalose is a superior non-permeating cryoprotectant to sucrose for vitrification of bovine ovarian tissue. The ovarian tissue was fragmented (1-2mm3) and divided into 6 different treatment groups. Tissues were vitrified in TCM199 supplemented with 15% EG, 15% DMSO, 20% calf serum and 0.5M sucrose or trehalose then placed in a cryovial or on a cryotop. After warming, the vitrified tissues were either immediately placed in 10% formalin (control) or on the chorioallantoic membrane of a 10-day old chicken embryo for 5 days. Follicles from control and vitrified tissue were observed under a light microscope for normal morphology and the total, normal and degenerated follicle densities were determined by standard stereological procedures. Sucrose and trehalose did not differ, nor was a difference observed between the cryovial and the cryotop for total, healthy or degenerated follicle density. Proportion of healthy follicles was higher in the control than all treatment tissues grafted to the CAM. All grafts placed on the traumatized CAM demonstrated presence of avian erythrocytes in the blood vessels after 5 days, but no difference was observed for blood vessel density among treatments. Lastly, the cooling rate of bovine ovarian tissue subjected to open and closed system devices for vitrification was evaluated. A thermocouple wire was used to determine the cooling velocity of 1-2mm3 fragments of bovine ovarian tissue placed on a cryotop (open system) or in a sealed cryovial (closed system). The cooling rate of tissues on the cryotop and in the cryovial was 7481±205.9° C/min and 664±26.0° C/min respectively.
In conclusion, the CAM supported the bovine ovarian tissue, thus the CAM culture system may be considered an acceptable alternative to traditional in vitro culture system for bovine ovarian tissue. Furthermore, angiogenesis may be an additional indication of ovarian tissue health. The hypotheses of our second study were refuted. Results indicated that sucrose and trehalose, and the cryotop and cryovial were equally effective in vitrifying bovine ovarian tissue.
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Wu, Tsung-Hsin, and 吳宗信. "The Application of Holstein Cattle Derived Placental Stem Cells and Amniotic Membrane Stem Cells on the Treatment of Ovarian Follicular Cyst." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/f4t5j7.
Full textAbstract:
碩士國立屏東科技大學
動物科學與畜產系所
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Taiwan is located in the subtropical and tropical zone. Hence, Holstein is prone to heat stress at high temperature and humidity. The negative energy balance which is caused by the decreasing of feed intake reduced the estrogen synthesis. Ovarian follicular cyst is the common reproductive disorder in lactating cows, and occupying approximately 6-19 % of dairy cows. The therapy of Gonadotropin-releasing hormone (GnRH) was conducted in the past. Nowadays, the problem of drug resistance and food safety draw attention. In recent years, studies have shown that stem cells hold the capability of self-renew and differentiation, and it shares the promise to replace the damaged tissues or produce the cytokines to promote the repairing of injured tissues. Therefore, this experiment is mainly to explore the feasibility of treating follicular cysts by infusion of cattle placenta stem cells (CPSCs) and cattle amniotic membrane stem cells (CAMSCs). The experiment of follicular cyst test was divided into four major groups (control group, hormone group, placental stem cells group, and amniotic stem cells group). The experimental cattle were raised in a concrete grounded barn with cow beds. The cattle were fed total mixed ration (TMR) twice a day, mineral salt, and drinking water during the experimental period. The experimental cattle were scanned the ovaries to identify the changes by means of ultrasound once a week and serum from the tail veins of the cattle were collected to analyze progesterone and estradiol concentration. The experimental periods were 49 days (two estrus cycles). If the estrus detector pedometer system showed that the cow is in heat, artificial insemination was performed 8 to 12 hours later. Therefore, the results demonstrated that the surface antigen analysis of placental stem cells and amniotic stem cells showed high levels of CD44 (98.6 % vs. 97.6 %) and a little amount of CD4 (2.0 % vs. 2.5 %) and CD105 (3.2 % vs. 0.2 %). The proliferation rate of amniotic stem cells at 48, 72, and 96 hours were significantly higher (P < 0.05) than placental stem cells respectively. By the approach of placental stem cells and amniotic stem cells for the treatment of follicular cysts shared extinguished outcomes. Injection of 1 and 6 million placental stem cells, the recovery rate occupies 75% and the estrus detection rate is reaching to 75%. Injection of 6 million amniotic stem cells also held better recovery rate than the injection of 1 million amniotic stem cells (100 % vs. 66.6 %) and the estrus rate (100 % vs. 33.3 %). Injection of 6 million placental stem cells and amniotic stem cells shared better recovery rate (100 % vs. 75 %) and estrus rate (100 % vs. 75 %) than the hormone groups. In conclusion, the infusion of 6 million placenta and amniotic stem cells therapy may hold the promise to replace traditional hormone therapy to improve the reproductive disorders of follicular cysts in dairy cows.
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Siphugu, Steven Mbonalo. "The efficiency of ultrasonorgraphy in monitoring ovarian structures and foetal development in goats, sheep and cattle as verified through laparoscopy and laparotomy." Diss., 2018. http://hdl.handle.net/11602/1148.
Full textAbstract:
MSCAGR (Animal Science)Department of Animal Science
The main purpose of this study was to assess the efficiency of ultrasonography in monitoring reproductive organs, pregnancy diagnosis, and foetal gender identification and to verify its reliability by laparoscopy and laparotomy, where applicable. Reproductive organs, pregnancy diagnosis and gender of the foetus were examined by A-mode ultrasound using 3.0 - 8.0 MHz trans-rectal transducer. A Sony Olympus Model laparoscope with a camera transducer was used to monitor the reproductive organs and pregnancy diagnosis. In monitoring the follicular dynamics, daily ultrasonography (ULTS) scanning was done for 17 days in sheep and for 21 days in both goats and cattle. Follicles of diameter ≥ 3 mm were selected for analysis of growth, ovulation and regression. For determining the efficiency of the techniques, laparoscopy (LAPSC) and laparotomy (LAPT) were used on days 3 and 10 of the goats and sheep oestrous cycle. The follicles were grouped into three categories according to their diameter as 3 - 4.9 mm, 5 - 7.9 mm and ≥ 8 mm, whereas the follicles of cattle were grouped as 3 - 4.9 mm, 5 - 9.9 mm and ≥ 10 mm. Early pregnancy diagnosis examinations were carried out from day 18 post insemination until pregnancy was confirmed. Foetal gender examinations were conducted from day 40 of pregnancy until the day the gender of the foetus was confirmed. Follicular development was accompanied by the occurrence of waves of follicular growth at different period of the oestrous cycle. The first follicular wave emerged on day 1.0 ± 0.4 in goats, 1.2 ± 0.4 in sheep and 2.2 ± 0.4 in cattle. The maximum diameter of the dominant follicles of observed follicular waves in goats was 7.3 ± 0.4 mm, 6.6 ± 0.2 mm, 7.3 ± 0.2 mm; in sheep was 6.4 ± 0.4 mm, 6.6 ± 0.4 mm and 6.7 ± 0.7 mm and in cattle was 13.1 ± 0.8 mm, 14.2 ± 0.6 mm and 15.7 ± 0.6 mm in wave 1, 2 and 3, respectively. However, the maximum size of the dominant follicle of the ovulatory wave in cattle was larger than the dominant follicles of both first and second waves, but in goats and sheep the dominant follicles were of similar size throughout the waves. In cattle, the ovulatory wave was shorter (p ˂ 0.05) than the duration of the first and second waves, while in sheep and goats were similar throughout the waves. In goats the total number of follicles counted in right and left ovaries under category 3 - 4.9 mm was lower with ULTS and LAPSC than with LAPT method (p ˂ 0.05). In sheep the mean number of follicles between 3 - 4.9 mm category in both right and left ovaries were different (p ˂ 0.05) between ULTS and LAPT. However, for categories 5 - 7.9 mm and ≥ 8 mm in both goats and sheep the mean numbers of follicles observed by all techniques were similar (p ˃ 0.05). In goats, pregnancy diagnosis accuracy improved from zero percent on day 18 to 100% on day 26 - 28, in sheep pregnancy diagnosis was 40% on day 18 and improved to 100% on day 20 - 22 vi of gestation. In cattle accuracy of pregnancy diagnosis was not possible at day 18 and gradually increased to 100% on day 30 - 32 of gestation. Out of 5 (100%) goat’s foetuses whose gender was determined, the diagnosis was correct in 100% (3/3) of the male foetuses and 100% (2/2) of the female foetuses. In sheep two foetuses were sexed as males while the other three were sexed as females and were both 100%. Out of 60% (3/5) of foetuses examined in cattle, 1 (100%) was identified as male and the remaining 2 (100%) were identified as females. The results obtained confirmed that the accuracy for foetal gender by ultrasonography was 100% in all foetuses observed. The current study demonstrated that trans-rectal ultrasonography examination is an efficient method for monitoring follicular dynamics, diagnosing pregnancy and foetal gender identification and that it is as reliable as laparoscopy and laparotomy where they were applied together.
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