Academic literature on the topic 'Bovine males'

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Journal articles on the topic "Bovine males"

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Mulder, Ann M., Paul A. Connellan, Christopher J. Oliver, Carol A. Morris, and Lesley M. Stevenson. "Bovine lactoferrin supplementation supports immune and antioxidant status in healthy human males." Nutrition Research 28, no. 9 (September 2008): 583–89. http://dx.doi.org/10.1016/j.nutres.2008.05.007.

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Jones, Arwel W., Simon J. S. Cameron, Rhys Thatcher, Marikka S. Beecroft, Luis A. J. Mur, and Glen Davison. "Effects of bovine colostrum supplementation on upper respiratory illness in active males." Brain, Behavior, and Immunity 39 (July 2014): 194–203. http://dx.doi.org/10.1016/j.bbi.2013.10.032.

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Shropshire, J. Dylan, Edward J. van Opstal, and Seth R. Bordenstein. "An optimized approach to germ-free rearing in the jewel waspNasonia." PeerJ 4 (August 9, 2016): e2316. http://dx.doi.org/10.7717/peerj.2316.

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Development of aNasonia in vitrogerm-free rearing system in 2012 enabled investigation ofNasonia-microbiota interactions and real-time visualization of parasitoid metamorphosis. However, the use of antibiotics, bleach, and fetal bovine serum introduced artifacts relative to conventional rearing ofNasonia. Here, we optimize the germ-free rearing procedure by using filter sterilizationin lieuof antibiotics and by removing residual bleach and fetal bovine serum. Comparison of these methods reveals no influence on larval survival or growth, and a 52% improvement in adult production. Additionally, adult males produced in the new germ-free system are similar in size to conventionally reared males. Experimental implications of these changes are discussed.
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Rouco, C., C. Jewell, K. S. Richardson, N. P. French, B. M. Buddle, and D. M. Tompkins. "Brushtail possum (Trichosurus vulpecula) social interactions and their implications for bovine tuberculosis epidemiology." Behaviour 155, no. 7-9 (2018): 621–37. http://dx.doi.org/10.1163/1568539x-00003512.

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Abstract The brushtail possum is the main reservoir of bovine tuberculosis in New Zealand. Disease prevalence is generally higher in males than in females. This has conventionally been assumed due to greater infection rates of males, but recent work has raised the hypothesis that it may instead be driven by survival differences. With bovine tuberculosis transmission among possums most likely occurring between individuals in close proximity, here we analyse social networks built on data from wild possums collared with contact loggers inhabiting a native New Zealand forest, to investigate whether there is mechanistic support for higher male infection rates. Our results revealed that adult female possums were generally just as connected with adult male possums as other adult males are, with male–female connection patterns not being significantly different. This result suggest that the new ‘survivorship’ hypothesis for the sex bias is more likely than the conventional ‘infection rate’ hypothesis.
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Motta-Delgado, Pablo Andrés, Ricardo Alberto Martínez-Tovar, Marliyanini Londoño-Giraldo, Erika Paola Rojas-Vargas, and Wilmer Herrera-Valencia. "Sero-prevalence of brucellosis (Brucella abortus) in bovines from Caquetá state, Colombia." Ciencia y Agricultura 17, no. 1 (February 9, 2020): 19–30. http://dx.doi.org/10.19053/01228420.v17.n1.2020.9917.

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Brucellosis is a disease with implications in the public health due both to its zoonotic character as its easy transmission trough of dairy products contaminated with the microorganism Brucella sp. The aim of this article was determinate the prevalence of bovine brucellosis in nine municipalities that carrying the 75% of bovine population in the Caquetá state, Colombia. Blood samples were collected in 100 herds dedicates to dual-purpose cattle, obtained blood serum from 1000 animals, of which 882 corresponding to cows. Rose Bengal Plate Test was performed and the confirmations of positive cases were made by competitive Elisa. The sero-prevalence of bovine brucellosis in Caquetá state was of 3.23% (95%, CI: 0-6.53%), in males 2.6% and females 3.29% respectively. At the municipal level, the sero-prevalence varied of 0 to 6.06%. The prevalence of brucellosis at herd level was of 22% (95%, CI: 12.24-31.76%). In conclusion, the sero-prevalence is low in bovines but moderate at the level of herds, therefore, it is necessary to increase the performance of the official control entities at the level of herds to reduce the high prevalence of the disease for guaranteed the safety of milk and thus the health of consumers.
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Timurkan, Mehmet Ozkan, Hakan Aydin, and Ahmet Sait. "Identification and molecular characterisation of bovine parainfluenza virus-3 and bovine respiratory syncytial virus - first report from Turkey." Journal of Veterinary Research 63, no. 2 (June 1, 2019): 167–73. http://dx.doi.org/10.2478/jvetres-2019-0022.

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AbstractIntroduction:Bovine parainfluenza virus-3 (BPIV3) and bovine respiratory syncytial virus (BRSV) are the cause of respiratory disease in cattle worldwide. With other pathogens, they cause bovine respiratory disease complex (BRDC) in ruminants. The aim of the study was the detection and molecular characterisation of BPIV3 and BRSV from nasal swabs and lung samples of cows in and around the Erzurum region of eastern Turkey.Material and Methods:In total, 155 samples were collected. Of animals used in the study 92 were males and 63 females. The age of the animals was between 9 months and 5 years, mean 1.4 years. Most males were in the fattening period and being raised in open sheds; females were in the lactating period and kept in free stall barns. All samples were tested for the presence of viral genes using RT-PCR. Gene-specific primers in a molecular method (RT-PCR) identified BRSV (fusion gene) and BPIV3 (matrix gene) strains at the genus level.Results:RNA from BRSV and BPIV3 was detected in two (1.29%) and three (1.93%) samples, respectively, one of each of which was sequenced and the sequences were aligned with reference virus strains. Phylogenetic analyses clustered the strains in genotype C/BPIV3 and subgroup III/BRSV.Conclusion:The results indicate that BRSV and BPIV3 contribute to bovine respiratory disease cases in Turkey. This is the first report on their detection and molecular characterisation in ruminants in Turkey.
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Pietersen, T., G. G. Bruwer, M. C. Smit, W. Bok, R. T. Naudé, and W. A. Vosloo. "Secondary sexual development (Masculinity) of bovine males: 2. Influence on certain meat quality characteristics." Meat Science 31, no. 4 (January 1992): 451–62. http://dx.doi.org/10.1016/0309-1740(92)90027-2.

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Atwill, Edward R., Sergio Maldonado Camargo, Ralph Phillips, Laura Herrera Alonso, Kenneth W. Tate, Wayne A. Jensen, Joe Bennet, Scott Little, and Terrell P. Salmon. "Quantitative Shedding of Two Genotypes of Cryptosporidium parvum in California Ground Squirrels (Spermophilus beecheyi)." Applied and Environmental Microbiology 67, no. 6 (June 1, 2001): 2840–43. http://dx.doi.org/10.1128/aem.67.6.2840-2843.2001.

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ABSTRACT Sixteen percent of California ground squirrels (Spermophilus beecheyi) were found to be shedding an average of 53,875Cryptosporidium parvum oocysts/g of feces. Male squirrels had a higher prevalence and higher intensity of shedding than did female squirrels. The majority of C. parvum isolates matched a bovine-murine genotype, with a few isolates resembling a porcine genotype. Higher intensities of shedding by males may enhance dissemination and genotypic mixing of this protozoa given males' proclivity to disperse to nonnatal colonies.
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Dobbs, K. B., D. Gagné, E. Fournier, I. Dufort, C. Robert, J. Block, M. A. Sirard, L. Bonilla, A. D. Ealy, and P. J. Hansen. "93 SEX-SPECIFIC DEVELOPMENTAL PROGRAMMING OF THE BOVINE EMBRYO BY COLONY STIMULATING FACTOR 2 (CSF2)." Reproduction, Fertility and Development 26, no. 1 (2014): 160. http://dx.doi.org/10.1071/rdv26n1ab93.

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Competence of the bovine embryo to establish pregnancy can be enhanced by treatment with colony stimulating factor 2 (CSF2) from Days 5 to 7 post-insemination. The mechanism is unknown but could involve developmental reprogramming. Here, we questioned whether treatment with CSF2 from Days 5 to 7 alters growth, interferon-τ (IFNT) secretion, and the methylome of extra-embryonic membranes (EEM) at Day 15. In vitro-produced embryos were treated with either 0 or 10 ng mL–1 bovine CSF2 from Days 5 to 7. Expanded blastocysts were transferred into synchronized recipients. On Day 15, conceptuses were recovered by flushing the uterus and sex determined by PCR (n = 4 males and 4 females per treatment). Statistical analysis of IFNT and length was performed using analysis of variance with the general linear models procedure of SAS (SAS Institute Inc., Cary, NC, USA). There was a sex × treatment interaction for conceptus length (P < 0.003) and IFNT in uterine flushing (P < 0.05) (as determined by antiviral activity). CSF2 increased length in males (least squares means ± s.e.m.: 93 ± 19 mm v. 20 ± 19 mm) and decreased length in females (22 ± 19 mm v. 103 ± 19). Similarly, CSF2 increased IFNT in males (45 483 ± 22 615 IU mL–1 v. –2536.27 ± 13 385 IU mL–1) and decreased IFNT in females (–14 012 ± 13 642 IU mL–1 v. 35 404 ± 7514.91 IU mL–1). The EmbryoGENE DNA Methylation Array (Edmonton, AB, Canada) was used to assess CSF2 effects at 418 805 positions across the genome in a subset of EEM (n = 2 for vehicle and 4 for CSF2 in males; n = 3 for vehicle and n = 3 for CSF2 in females). CSF2 caused hypermethylation for 9842 probes in males and 6227 probes in females and hypomethylation for 9322 probes in males and 3292 probes in females. An analysis was conducted to evaluate if clusters of differentially-methylated probes were non-randomly distributed spatially in 5 Mb regions of individual chromosomes using a 500-kb moving window. Statistical significance was determined using chi-squared tests for each 500-kb window. Differential methylation was not uniformly distributed but rather there were regions or hyper- and hypomethylation that varied with sex. The most common situation was where a region was differentially methylated in one sex but not the other. In some cases, a region was differentially methylated in opposite directions for males and females. For example, a region of BTA1 between positions 67 Mb–77.5 Mb contained 1632 probes, of which 59 probes were hypo-methylated in males and 35 were hypermethylated in females. In conclusion, changes in developmental programming of the bovine embryo caused by CSF2 occur in a sex-specific manner. This result suggests a possible mechanism by which environmental effects on the female affect male embryos differently than female embryos. Support was provided by U.S. Department of Agriculture (USDA) National Institute of Food and Agriculture (NIFA) grant 2011-67015-30688.
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Guerra, Neurisvan Ramos, Bruno Henrique Leal e. Silva Alves, Márcia Paula Oliveira Farias, Rinaldo Aparecido Mota, and Leucio Câmara Alves. "Frequency of Toxoplasma gondii antibodies in bovines in the state of Pernambuco, Brazil." Revista Brasileira de Parasitologia Veterinária 23, no. 3 (September 2014): 417–19. http://dx.doi.org/10.1590/s1984-29612014056.

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Toxoplasmosis is a parasitic disease caused by Toxoplasma gondii that affects homeothermic animals, including humans. Felines are considered the definitive host of this parasite, while other animals act as intermediate hosts. The purpose of this study was to assess the frequency of anti-T. gondii IgG antibodies in bovines in the state of Pernambuco, Brazil. Serum samples (n = 427) from animals in 13 municipalities of the coastal forest/plantation region of the state were analyzed using the immunofluorescent antibody test (IFAT). The overall results revealed a prevalence rate of 16.63% (27/427). High percentages of positivity were found among animals aged 25 to 36 months (28.57%; 30/42) and in males (22.22%; 2/9). The present findings suggest that bovine toxoplasmosis is endemic in the area under study.
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Dissertations / Theses on the topic "Bovine males"

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Jones, Arwel W. "Effects of bovine colostrum on immune responses to prolonged exercise and upper respiratory illness in active males." Thesis, Aberystwyth University, 2014. http://hdl.handle.net/2160/658e92e5-7728-46bd-9d96-62dbf88e7acc.

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It is now well established that exercise of a strenuous and/or prolonged nature can lead to transient perturbations in immune function. The clinical significance of participating in such acute bouts of exercise in combination with other life stressors (e.g. inadequate nutrition) may be an increased incidence of upper respiratory illness (URI) (e.g. sore throat, runny nose). Many proposed nutritional countermeasures to exercise-induced immune dysfunction have been shown to be ineffective. The aims of this thesis were to determine the effects of bovine colostrum (COL) on in vitro and in vivo measures of immunity taken at rest and/or following prolonged (≥ 2 h) exercise and the incidence of URI during regular training in active males. Study 1 (Chapter 3) demonstrated that acute COL supplementation improved the recovery of bacterial stimulated neutrophil degranulation and enhanced salivary lysozyme concentration following 2.5 h of cycling. There was also greater fMLP-stimulated oxidative burst throughout the COL trial compared to PLA. These effects are suggested to be partly due to components and/or metabolites of COL that become bioavailable following digestion of the supplement which may explain why Study 2 (Chapter 4) demonstrated a greater effect on fMLP-stimulated oxidative burst with 4 weeks of COL supplementation. Study 3 (Chapter 5) found a lower proportion of URI days and lower number of URI episodes with 12 weeks of COL supplementation. Although there was no effect on selected measures of in vitro immune function taken at rest (fMLP oxidative burst, salivary secretory IgA and antimicrobial peptides), COL did blunt increases in salivary bacterial load over the winter period, which may provide a novel marker of in vivo immunity. Despite no effect of prior infection with Epstein-Barr virus (EBV) on URI incidence in Study 4 (Chapter 6), those who were seropositive and undergoing COL supplementation had a lower number of URI days vii than seronegative counterparts. Study 5 (Chapter 7) observed a lack of effect of COL supplementation on the overall magnitude of an in vivo measure of T-cell-mediated immunity to a novel antigen following prolonged exercise but there was evidence that COL may increase the sensitivity of responses to such antigenic challenge.
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Huddleston, Gloria Gradine. "Steroid Sensitive Neurons and Male Rat Mating Behavior." Digital Archive @ GSU, 2006. http://digitalarchive.gsu.edu/biology_diss/12.

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Male rat mating is a suite of individual behaviors mediated by the actions of two metabolites of testosterone (T), dihydrotestosterone (DHT) and estradiol (E2), on the brain. Individually, neither metabolite fully maintains or restores mating in castrated males, but both combined are as effective as T. Two hormone-responsive areas of the brain, the medial preoptic area (MPO) and the medial amygdala (MEA), are crucial for mating. These studies ask: by what mechanism(s) does E2 act in the MPO and MEA? We blocked the conversion of T to E2 in the MEA of intact male rats and sexual behavior was not maintained. We then infused antisense oligodeoxynucleotides (ODNs) to estrogen receptor-alpha (ER-á) mRNA bilaterally to the MPO or the MEA of intact male rats to block ER-á expression. ODN infusion of the MPO attenuated mating but infusion of the MEA had no effect. These results suggest that ER-á is the behaviorally relevant estrogen receptor (ER) in the MPO but not in the MEA. ER was originally described in the cytoplasm and nucleus of cells. Recently plasma membrane associated ERs (mER) have been reported. We conjugated E2 to Bovine Serum Albumin (BSA-E2), a large protein that will not penetrate the plasma membrane, thus restricting the action of E2 to mER, and chronically delivered it to the MPO and MEA. BSA-E2 maintained mating if put in the MPO, but not in the MEA, suggesting a surface action of E2 is sufficient in the MPO. The MPO and MEA are reciprocally connected and probably constitute elements of a larger, steroid-responsive neural network that mediates male mating behavior. To begin to describe this purported circuit, we injected Pseudorabies virus (PRV) into the prostate gland and dually labeled PRV-immunoreactive cells for ER or androgen receptors. We found dual labeling in a forebrain diencephalic circuit that includes the MPO, the medial preoptic nucleus, bed nucleus of stria terminalis, the zona incerta, the periaqueductal gray and other areas that presumably mediate both autonomic and motor aspects of male mating. Together, the results of these studies begin to elucidate locations and mechanisms of E2 mediation of male sexual behavior.
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Suyatno. "Establishment of Long-Term Culture of Bovine Undifferentiated Germ Cells Isolated from Adult and Immature Testes." Kyoto University, 2018. http://hdl.handle.net/2433/232367.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第21166号
農博第2292号
新制||農||1061(附属図書館)
学位論文||H30||N5140(農学部図書室)
京都大学大学院農学研究科応用生物科学専攻
(主査)教授 今井 裕, 教授 久米 新一, 准教授 南 直治郎
学位規則第4条第1項該当
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Moro, Guidiane. "Processamento do milho ou sorgo em dietas de alto grão, na terminação de bovinos mestiços leiteiros." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/4381.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
In order to assess the use of high grain diets, corn or sorghum offered as the entire form or ground, the termination in male animals in confinement, crossbred dairy origin, an essay was conducted at the Escola de Medicina Veterinária e Zootecnia (EMVZ) the Universidade Federal do Tocantins (UFT), in the municipality of Araguaína, in the North region of Brazil, between October 2013 and January 2014, lasting 109 days. It was used 28 crossbred steers whole, from crosses of European breeds with zebu breeds, with an average age of 30 months and average weight of 238 ± 6,1 kg. Four treatments were tested: MGI) whole corn; MGM) Grounded Corn; SGI) Whole Sorghum; and SGM) Grounded sorghum. These diets were formulated targeting an average daily weight gain of 1,5 kg/day/animal, with 100 % concentrate, on a dry matter basis. After a period of 109 days, the animals were slaughtered and subsequently to this period, were made evaluations of temperature, pH, carcass conformation, based on muscular expression and physiological maturity, based on ossification of the vertebrae and ribs. The marbling assessments, color and texture of meat were held. Chemical composition of the meat was performed on sample taken from caudal face of the Longissimus dorsi. The steaks were undergone by evaluators trained in sensory analysis panel. It was evaluated the levels of dry matter, crude protein, ether extract, neutral detergent fiber, acid detergent fiber, non-fiber carbohydrate, total carbohydrates and total digestible nutrients, and their respective apparent digestibility. It was also evaluated the total weight gain, average daily gain, feed efficiency and feed conversion. The experiment was conducted as a completely randomized design with the treatments distributed in a factorial arrangement 2 x 2, being used seven replications (animals) per treatment. According to analyzes carried out by this study, it is concluded that the best performances of average daily intake, feed conversion and body condition score were obtained in diets that used kernel of corn in the ground form, while the meat and carcass performance, treatment with sorghum grain in the entire form, obtained better results.
Com o objetivo de avaliar o uso de dietas de alto grão, milho ou sorgo, fornecidos nas formas inteira ou moída, na terminação em confinamento de animais machos, mestiços de origem leiteira, foi realizado um experimento na Escola de Medicina Veterinária e Zootecnia (EMVZ) da Universidade Federal do Tocantins (UFT), localizada no município de Araguaína, situada na região Norte do Brasil, entre outubro de 2013 e janeiro de 2014, com duração de 109 dias. Utilizou-se 28 novilhos mestiços inteiros, provenientes de cruzamentos de raças taurinas com raças zebuínas, com idade média de 30 meses e peso médio inicial de 238 ± 6,1 Kg. Foram testados quatro tratamentos, MGI) Milho inteiro; MGM) Milho Moído; SGI) Sorgo inteiro; e SGM) Sorgo Moído, essas dietas foram formuladas visando um ganho de peso médio diário de 1,5 kg/dia/animal, apresentando 100% de concentrado, com base na matéria seca. Depois do período de 109 dias os animais foram abatidos, e posteriormente a este período foram feitas avaliações de temperatura, pH, conformação, baseada na expressão muscular e maturidade fisiológica, baseada na ossificação das vértebras e costelas. Foram realizadas as avaliações de marmoreio, coloração e textura da carne. A composição química da carne foi realizada em amostra retirada da face caudal do Longíssimus dorsi. Os bifes foram submetidos a avaliações através de avaliadores treinados no painel de análise sensorial. Avaliou-se os níveis de matéria seca, proteína bruta, extrato etéreo, fibra em detergente neutro, fibra em detergente ácido, carboidratos não fibrosos, carboidratos totais e nutrientes digestíveis totais, além de suas respectivas digestibilidades aparentes. Também foram avaliados o ganho de peso total, ganho médio diário, eficiência alimentar e conversão alimentar. O experimento foi realizado com delineamento inteiramente casualizado, sendo os tratamentos distribuídos em arranjo fatorial 2 x 2, sendo utilizado sete repetições (animais) por tratamento. De acordo com análises realizadas através desse estudo, conclui-se que os melhores desempenhos de consumo médio diário, conversão alimentar e escore de condição corporal foram obtidos nas dietas que utilizaram grão de milho na forma moída, enquanto que no desempenho de carne e carcaça, o tratamento com grão de sorgo na forma inteira, obteve melhores resultados.
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Perrier, Jean-Philippe. "Epigénétique de la semence bovine : analyse moléculaire de la qualité de la semence et impact potentiel sur le développement embryonnaire." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLA037/document.

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La présence de taureaux sub-fertiles sur le marché de l’Insémination Animale (IA) influence négativement l’efficacité des élevages. L’évaluation de la fertilité des taureaux, basée sur l’analyse combinée de marqueurs génétiques, morphologiques, cinétiques et métaboliques de la semence, n’est pas suffisante pour identifier les taureaux sub-fertiles avant leur entrée en production. Cela suggère l’implication d’autres facteurs, notamment d’origines épigénétiques. Parmi les marques épigénétiques, la méthylation de l’ADN tient une place essentielle : son remaniement est en effet indispensable aux processus fondamentaux que sont la différenciation des cellules germinales, la spermatogénèse et le développement embryonnaire précoce. Alors que chez l’Homme, de nombreuses études ont montré que des altérations des profils de méthylation spermatiques sont associées à la sub-fertilité, très peu de données existent chez le bovin. L’objectif de ce travail de thèse est la caractérisation du méthylome de la semence bovine et l’identification de nouveaux marqueurs fiables de la fertilité mâle à un stade précoce. Cette étude s’inscrit dans un large projet intitulé SeQuaMol (pour « Qualité Moléculaire de la Semence »), mis en place au sein d’un laboratoire commun entre l’INRA et la fédération ALLICE. La caractérisation du méthylome spermatique bovin a été réalisée en utilisant une approche multi-échelle (globale, pangénomique et séquence-spécifique). Les analyses ont permis de révéler l’hypométhylation très marquée du spermatozoïde bovin. L’hypométhylation affecte des gènes importants pour la différenciation de la lignée germinale, les fonctions spermatiques, ainsi que des séquences satellites. L’identification de biomarqueurs de la fertilité a été réalisée en utilisant une approche pangénomique (Reduced Representation Bisulfite Sequencing, RRBS). L’analyse a été effectuée sur une cohorte de 94 taureaux, dont les individus de races Holstein et Montbéliard ont été catégorisés en fonction de l’adéquation entre un indicateur génétique de la fertilité et leur fertilité réelle. Le dispositif inclus également des taureaux de 4 autres races pour obtenir une estimation de la variabilité épigénétique liée à la race. Cette analyse a nécessité l’optimisation et l’automatisation du protocole pour la préparation des banques RRBS à haut-débit, ainsi que la mise au point de l’ensemble de la procédure de traitement bio-informatique et statistique des données. Plusieurs milliers de biomarqueurs de la fertilité ont été identifiés et permettent de prédire de façon robuste le statut de fertilité. De plus, une démarche d’intégration des données de génotype et d’épigénotype a été amorcée, soulignant les interactions potentielles en ces strates d’informations. Enfin, nous avons mis en évidence l’influence de l’âge à la production de semence sur le méthylome. L’ensemble de ces données souligne que les modifications du méthylome spermatique peuvent affecter des gènes impliqués dans les processus précoces et plus tardifs du développement, ainsi que quelques voies du fonctionnement du spermatozoïde. L’ensemble des biomarqueurs identifiés serviront de base à la poursuite du projet SeQuaMol, dont l’aboutissement sera le développement d’outils technologiques et statistiques pouvant être utilisés en routine pour améliorer la prédiction de la fertilité mâle
The presence of subfertile bulls in the market of Animal Insemination negatively influences the efficacy of breeding farms. The evaluation of bull fertility, based on the combined analysis of genetic, morphological, kinetic and metabolic markers of the semen, is not sufficient to identify subfertile bulls before entering semen production. It suggests the implication of other factors, especially epigenetic ones. Within the epigenetic markers, DNA methylation holds a crucial position: indeed, its reprogramming is indispensable to the fundamental processes that are germinal cell differentiation, spermatogenesis and the embryonic development. Whereas several studies have showed that the alteration of spermatic methylation profiles are associated with subfertility in humans, only a little data exists concerning bovines. The aim of this thesis is the characterization of the methylome of bovine semen and the identification of new reliable markers of male fertility at an early stage. This study is part of a larger project called SeQuaMol (Molecular Quality of Semen) which rely on a common laboratory between INRA and the ALLICE federation. The characterization of the bovine sperm methylome was achieved by using a multiscale approach (global, pangenomic and sequencespecific). The analyses made it possible to observe the hypomethylation of the bovine semen. Hypomethylation affects genes that are crucial for the differentiation of the germline, spermatic functions, and also on satellite sequences.The identification fertility biomarkers was carried out by using a pangenomic approach (Reduced Representation Bisulfite Sequencing, RRBS). The analysis has been performed on a cohort of 94 bulls, including subjects of the Holstein race and Montbeliard race, categorized according to the adequacy between a genetic indicator of fertility and their actual fertility. The process also includes bulls from 4 other breeds in order to obtain an estimate of the genetic variability linked to the breed. This analysis has required the optimization and the automation of the protocol for the high throughput preparation of RRBS libraries, as well as the development of the whole bioinformatic pipeline and data statistics. Several thousands of biomarkers of fertility have been identified, which allow to predict in a robust way the fertility status. Furthermore, a process of integration of genotype and epigenotype data has been started, which underlines the potential interaction between these levels of information. Finally, we have highlighted the influence of the age of semen production on the methylome. Altogether, theses data suggest that modifications of the semen methylome can affect genes that are involved in the process of early and late embryo development, and parts of the functioning of the sperm cell. The biomarkers identified will form a basis for the pursuit of the SeQuaMol project, of which the completion will be the development of technological and statistical tools that may be used routinely to improve male’s fertility prediction
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Menezes, Leonardo de Melo. "Bioestimulação na eficiência reprodutiva em bovinos de corte." Universidade Federal de Pelotas, 2010. http://repositorio.ufpel.edu.br/handle/ri/2639.

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The objective of this study was to evaluate the reproductive performance of beef heifers, in a range breeding system, exposed or not to different sexual biostimulation treatments. Was used 220 heifers, Aberdeen Angus breed, with 273 average kg and age of 24 months. Heifers were divided into three groups: One group using teaser bull, and consisted of 73 heifers exposed for 60 days previous AI to vasectomized previously males. The second group consisted of 73 heifers exposed to the same period to androgenized cows. The third group was 74 heifers as a control group and did not receive biostimulation treatments. The three groups were remained separate, allocated on average 600 meters distant from each other. All heifers were submitted to gynecological exam in the beginning of biostimulation, and were diagnosed sexually mature or immature. After the treatments, all heifers began to be managed as a single group, and started the breeding season, using conventional artificial insemination method for 45 days. After the end of this period, the breeding season was complemented using natural breeding for 45 days. Variables analyzed were the weight at the beginning at the end of treatment, the diary gain average, the pregnancy rate, and the interval between the start of breeding season to conception. Fixed factors considered were the three treatments. 10 Frequency of heifers within treatments and within factor pregnancy rate was analyzed using the chi-square. Weights at the beginning and end of treatment and conception moment were analyzed by analysis of variance (ANOVA) followed by Tukey test. There was no difference between treatments for the variables weight and pregnancy rate. Heifers biostimulatated with androgenized cow had a earlier conception , than thosed bioestimulated with teaser bull.
Objetivou-se avaliar o desempenho reprodutivo de novilhas de corte, criadas em condições extensivas, quando expostas ou não a distintos tratamentos bioestimulatórios. Foram utilizadas 220 novilhas de corte, da raça Aberdeen Angus, com peso médio de 273 kg e idade média de 24 meses. Os animais foram separados em três grupos: O primeiro grupo, denominado rufião, foi formado por 73 animais, expostos por 60 dias pré-inseminação artificial a machos previamente submetidos à cirurgia de caudectomia epididimária. O segundo grupo, formado por 73 animais expostos pelo mesmo período a vacas androgenizadas. O terceiro grupo, formado por 74 animais foi o grupo controle e não recebeu exposição de tratamentos bioestimulatórios. Os três grupos foram mantidos separados, em potreiros alocados em média 600 metros distantes entre si. Todos os animais passaram por avaliação ginecológica no início do período de bioestimulação, onde foram diagnosticadas as novilhas sexualmente maturas ou imaturas. Após os tratamentos, os animais passaram a ser manejados como um único grupo, e iniciou-se a estação de acasalamento, através de inseminação artificial convencional, por 45 dias. Após o término deste período, a estação de acasalamento foi complementada utilizando-se monta natural por mais 45 dias, na proporção macho fêmea de 1:25. As variáveis estudadas foram o peso vivo ao início ao fim dos tratamentos, a taxa de prenhez, medida pelo diagnóstico de gestação por palpação retal 60 dias após o fim do 8 acasalamento, e o intervalo entre o início do acasalamento até a concepção. Para calcular este intervalo, foram regredidos 283 dias da data de parto (período médio da gestação da raça), em seguida ajustando-se à data de inseminação das novilhas. Os fatores fixos considerados foram os três tratamentos. A freqüência de novilhas dentro dos tratamentos e dentro do fator taxa de gestação foi analisada através do teste de Qui-quadrado. Os pesos ao início e fim dos tratamentos e o momento de concepção foram analisados por análise de variância (ANOVA), seguida de teste de Tukey. Não houve diferença entre os tratamentos, para as variáveis peso e taxa de prenhez. Novilhas bioestimuladas por vacas androgenizadas apresentaram concepção mais precoce, sendo preferencial ao método por rufiões machos caudectomizados.
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7

Huamán, Gonzáles Juan Carlos. "Prevalencia del virus de la diarrea viral bovina, y animales persistentemente infectados con el virus, en hatos productores de leche de la irrigación de Majes, Arequipa." Bachelor's thesis, Universidad Nacional Mayor de San Marcos, 2006. https://hdl.handle.net/20.500.12672/686.

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El objetivo del presente estudio fue determinar la prevalencia del virus de la diarrea viral bovina (VDVB) y de animales persistentemente infectados (PI), en bovinos productores de leche en la Irrigación de Majes, provincia de Caylloma, Arequipa. El estudio fue efectuado en tres fases consecutivas. En la primera, se colectaron 204 muestras de leche de tanque (uno por hato) en la planta de procesamiento de la empresa Gloria S.A., para la detección de anticuerpos contra el VDVB mediante la prueba de ELISA indirecta. En la segunda fase se seleccionaron de modo arbitrario 57 hatos positivos a anticuerpos contra el VDVB con densidades ópticas (DO) iguales o mayores a 0.900, de los animales de estos hatos se colectaron 286 muestras de suero sanguíneo, para conocer el status serológico de cada animal y la búsqueda de animales PI mediante ELISA indirecta y ELISA de captura respectivamente. En la tercera fase se obtuvieron muestras de suero de la totalidad de terneras y vaquillas (n igual a 20) de tres hatos que tuvieron animales PI en busca de más animales PI. El 98.04 ± 1.90% (200/204) de las muestras de leche resultaron positivas a anticuerpos contra el VDVB con DO que fluctuaron entre 0.300 a 2.350.
--- The aim of this study was to determine the prevalence of bovine viral diarrhoea virus (BVDV) and persistently infected (PI) animals, in dairy herds located in Majes Arequipa, Peru. The study was carried out in three steps. In the first step, 204 bulk tank milk samples corresponding to 204 herds were taken at Gloria S.A. processing plant in Majes for detection of antibodies against BVDV by indirect ELISA test. In the second step, 286 blood samples were taken from 57 strong positive (Optical Density [OD] ³ 0.900) herds for antibodies against BVDV and PI animals’ detection by indirect and capture ELISAs respectively. In the third step, blood samples were taken from all the animals up to 6 to 24 months old from three herds that have at least one PI animal. The prevalence of BVDV in the 204 herds was 98.04 ± 1.90% (200/204), the levels of antibodies ranged from 0.300 to 2.350 OD.
Tesis
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Silva, Luiz Henrique Pereira. "Effect of castration and maturity on body glucose sensitivity, carcass composition, meat quality traits and muscle proteome and phosphoproteome of Nellore male cattle." Universidade Federal de Viçosa, 2018. http://www.locus.ufv.br/handle/123456789/21004.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
O presente trabalho consiste de quatro manuscritos desenvolvidos usando os mesmos animais. O objetivo do primeiro estudo foi avaliar o efeito de castração sobre as características de carcaça e qualidade da carne de Nelore abatidos em diferentes pesos corporais (PC). Trinta e seis bezerros Nelore (Bos taurus indicus) com média inicial de 256,1 ± 3,05 kg de PC e 8,2 ± 0,07 meses de idade foram utilizados, sendo que a metade foi aleatoriamente selecionada para a castração cirúrgica uma semana antes do desmame. Os bezerros desmamados foram confinados recebendo uma mesma dieta, e seis bezerros de cada condição sexual foram distribuídos aleatoriamente para serem abatidos quando a média do PC atingisse 280, 380 e 480 kg. Portanto, este estudo foi realizado seguindo delineamento inteiramente casualizado com tratamentos arranchados em esquema fatorial com 2 condições sexuais (castrado vs. inteiro) e 3 pesos de abate (280, 380, e 480 kg). As características de qualidade da carne foram avaliadas aos 1, 7 e 14 dias postmortem. O efeito de interação foi encontrado (P <0,01) para a gordura intramuscular e para a gordura renal, pélvica e cardíaca. A carcaça de boi inteiro foi mais pesada (P <0,05) do que de castrados. A carcaça do boi inteiro teve maior (P <0,05) espessura de cobertura. Castração reduziu a força de cisalhamento e aumentou o índice de fragmentação miofibrilar aos 14 dias postmortem. As carcaças do abate aos 480 kg apresentaram um resfriamento mais lento, um sarcômero mais longo e uma menor força de cisalhamento quando avaliada a 1 dia postmortem. A redução na força de cisalhamento de 1 para 14 dias post-mortem foi reduzida (P <0,05) à medida que se aumentou o peso corporal ao abate. Conclui-se que, excetuando a gordura da carcaça, a castração e o peso corporal na colheita afetam as características de carcaça e carne independentemente. O segundo estudo teve como objetivo avaliar a sensibilidade à glicose de bovinos Nelore castrados e inteiros ao longo do desenvolvimento corporal. Além disso, foram avaliadas a expressão gênica de biomarcadores relacionados ao metabolismo da glicose, crescimento muscular e tal, enquanto o pesodeposição de lipídios. Para tanto, os mesmos animais do primeiro estudo foram utilizados, e este estudo foi realizado seguindo delineamento inteiramente casualizado com tratamentos arranchados em esquema fatorial com 2 condições sexuais (castrado vs. inteiro) e 3 pesos de abate (280, 380, e 480 kg). Dois testes de tolerância à glicose (TTG) foram realizados aos 380 e 480 kg de PC. Longissimus dorsi (LD) foi amostrado logo após a sangria para a expressão gênica. A composição da carcaça e o desempenho animal foram avaliados. Animais não castrados tiveram maior PC final (P = 0,02) e tendência para aumentar a eficiência alimentar (P = 0,08) em relação aos castrados. Os bovinos inteiros tiveram maior rendimento de carne magra (P = 0,02) e proteína (P = 0,01) do que os castrados. Efeito de interação foi encontrado para o ganho de gordura de carcaça (P = 0,01), e os castrados ganharam mais gordura de carcaça do que os inteiros apenas de 380 a 480 kg de PC. A taxa fracional de acumulação de proteína da carcaça (FAR) diminuiu à medida que os bovinos aumentaram o PC (P <0,01). Nem o nível basal da glicose nem a área sob a curva (AUC) pós-infusão foram afetados pela castração ou PC dos bovinos (P > 0,05). A expressão de genes relacionados ao metabolismo da glicose no LD não foi afetada pela castração ou PC dos bovinos (P> 0,05). Foi observada uma tendência de aumento na expressão de LD de acetil-CoA carboxilase alfa (ACACA) pela castração (P = 0,086). Efeitos de interação (P <0,05) foram encontrados para a expressão do receptor de IGF-1 (IGF1R) e da proteína F-box 32 (FBXO32) no LD, e para ambos os genes, os novilhos apresentaram a maior abundância de mRNA aos 380 kg de PC, enquanto os inteiros tiveram a maior abundância aos 480 kg de PC. A expressão de serpin A3-6 no LD tendeu (P = 0,08) a reduzir com aumento do PC de 280 para 480 kg. Em conclusão, apesar do aumento na gordura da carcaça pela castração e aumento do PC, a sensibilidade corporal de bovinos Nelore à glicose não muda. Para o terceiro estudo, as amostras de LD coletadas no momento do abate foram utilizadas para comparar o proteoma e o fosfoproteoma de bovinos Nelore castrados ou não durante os diferentes estádios de crescimento. A proteína muscular extraída foi separada em 2D-PAGE e corada sequencialmente com Pro-Q Diamond e Coomassie coloidal. Posteriormente, realizou-se uma análise comparativa do perfil protéico, e os spots diferencialmente abundantes foram excisados para identificação de proteínas por MALDI-TOF/TOF. A castração afetou (P <0,05) a abundância de 6 fosfoproteínas e 10 spots de proteína total, enquanto o peso corporal afetou (P <0,05) abundância de 34 fosfoproteínas e 29 spots de proteína total. A castração diminuiu (P <0,05) a abundância de duas enzimas glicolíticas da fase de produção de energia, sugerindo que o aumentou na via da glicólise promove síntese de glicerol-3P para dar suporte a uma maior deposição de gordura em novilhos. Em relação ao estágio de crescimento, além das proteínas estruturais da cadeia leve reguladora de miosina 2 (MYLPF) e da actina alfa 1 (ACTA1), a maioria das proteínas identificadas estão relacionada ao metabolismo energético, incluindo o metabolismo do glicogênio, glicólise, fosforilação oxidativa, metabolismo da creatina-fosfato, e metabolismo citosólico de NADH. Esses resultados sugerem que a diminuição da taxa de crescimento muscular reduz a glicólise e a geração de ATP no músculo. No quarto estudo utilizou-se apenas os doze bovinos Nelore abatidos aos 480 kg de PC. O objetivo deste estudo foi avaliar as diferenças no proteoma e fosfoproteoma entre bovinos Nelore castrados e inteiros durante a conversão do músculo em carne, bem como após 14 dias de maturação. Foram utilizados 12 bezerros machos Nelore (247 kg e 8 meses) e seis bezerros foram selecionados aleatoriamente para a castração cirúrgica uma semana antes do desmame. Os bezerros desmamados foram alimentados com a mesma dieta e foram abatidos após 230 dias de confinamento. O músculo Longissimus foi amostrado logo após a sangria (0d pós- morte), na desossa (1d pós-morte) e após a maturação (14d pós-morte) para análise de proteoma. As características de carcaça foram avaliadas na desossa e a força de cisalhamento da carne foi medida ao 1, 7 e 14 dias postmortem. O extrato de proteína muscular foi separado por 2D-PAGE e corado sequencialmente para fosfoproteína (Pro- Q Diamond) e para proteína total (Coomassie coloidal). Os spots diferencialmente abundantes entre a condição sexual ou entre os tempo pós-morte foram excisados para identificação de proteínas por MALDI-TOF/TOF. A castração aumentou (P <0,05) a abundância de enzimas glicolíticas, enquanto que a proteína da fosforilação oxidativa ATP5B foi reduzida (P <0,05). Além disso, a abundância de troposina T isoforma rápida (TNNT3) foi aumentada pela castração (P <0,05), enquanto a isoforma lenta (TNNT1) tendeu a diminuir (P <0,10). A creatina quinase tipo-M foi marcadamente fragmentada no postmortem. A abundância de PGM1 fosforilada aumentou durante as primeiras 24 horas pós-morte e foi altamente correlacionada com o pH da carcaça. A abundância de uma proteína de choque termico 71 kDa (HSC70) aumentou marcadamente após a maturação. Além disso, a abundância das proteínas miofibrilares fosforiladas ACTA1 e MYLPF foram positivamente correlacionadas com o encurtamento do sarcômero. Em conclusão, nossos dados demonstraram que a abundância e a fosforilação das enzimas glicolíticas afetam a qualidade da carne durante a conversão do músculo em carne. No geral, a castração aumentou acentuadamente a gordura da carcaça e a gordura intramuscular, enquanto que a sensibilidade corporal à glicose e a conversão do músculo na carne parecem ser semelhantes entre bovinos castrados e não castrados.
The current work consists of four manuscripts developed using the same animals.The objective of the first study aimed to evaluate the castration effect on carcass and meat traits of Nellore cattle harvested at different body weights (BW). Thirty-six Nellore (Bos taurus indicus) calves averaging 256.1 ± 3.05 kg of BW and 8.2 ± 0.07 months old were used, within then half was randomly selected for surgical castration one-week prior weaning. Weaned calves were fed with the same diet, and then six calves from each sex condition were randomly assigned to be harvested when the average BW of both sex conditions reaches 280, 380, and 480 kg. Therefore, this study was carried out as a complete randomized design following a 2 (sex condition) by 3 (weight at harvest) factorial arrangement of treatments. Beef traits were evaluated at 1, 7, and 14 d postmortem. Interaction effect was found (P < 0.01) for intramuscular fat and for kidney, pelvic and heart fat. Bull carcass was heavier (P < 0.05) than steer. Steer carcass had greater (P < 0.05) backfat thickness. Castration reduced shear force and increased myofibrillar fragmentation index at 14 d postmortem. Carcasses from cattle harvested at 480 kg had slower chilling, longer sarcomere, and lower shear force at 1 d postmortem. Shear force change from 1 d to 14 d postmortem reduced (P < 0.05) as harvest body weight increased. In conclusion, despite of carcass fatness, castration and body weight at harvest affect carcass and meat traits independently. The second study aimed to evaluate the glucose sensitivity of bulls and steers throughout body development. In addition, it was evaluated gene expression of biomarkers related to glucose metabolism, muscle growth and lipid deposition. Therefore, the same animals from the first study were used, and this study was carried out as a complete randomized design following a 2 (sex condition) by 3 (weight at harvest) factorial arrangement of treatments. Two glucose tolerance tests (GTT) were performed at 380 and 480 kg. Longissimus dorsi (LD) was sampled just after stunning for gene expression. Carcass composition and animal performance were evaluated. Bulls had greater final BW (P = 0.02) and tended to increase G:F ratio (P = 0.08) compared with steers. Bulls had greater carcass yield of lean (P = 0.02) and protein (P = 0.01) than steers. An interaction effect was found for carcass fat gain (P = 0.01), and steers gained more carcass fat than bulls only from 380 to 480 kg of BW. Carcass protein fractional accretion rate (FAR) decreased as cattle BW increased (P < 0.01). Neither glucose basal level nor area under the curve (AUC) post-infusion were affected by castration or cattle BW (P > 0.05). Expression of genes related to glucose metabolism in the LD were not affected by castration or cattle BW (P > 0.05). Castration tended (P = 0.086) to upregulate LD expression of Acetyl-CoA carboxylase alpha (ACACA). Interaction effects (P < 0.05) were found for LD expression of IGF-1 receptor (IGF1R) and F-box protein 32 (FBXO32), and for both genes steers had the greatest mRNA abundance at 380 kg while bulls had the greatest abundance at 480 kg of BW. The LD expression of serpin A3-6 tended (P = 0.08) to be downregulated as cattle BW increased from 280 to 480 kg. In conclusion, despite of the carcass fatness enhancement by castration and increasing BW, Nellore cattle whole-body sensitivity to glucose does not change. For the third study, the LD sampled at the harvest were used to compare the proteome and phosphoproteome of Nellore bulls and steers during different growth stages. Extracted muscle protein was separated in a 2D-PAGE and stained sequentially with Pro- Q Diamond and Colloidal Coomassie. Afterward, a comparative analysis of protein profile was performed, and differentially abundant protein spots were excised for protein identification by MALDI-TOF/TOF. Castration affected (P < 0.05) abundance of 6 phosphoproteins and 10 protein spots, while body weight affected (P < 0.05) abundance of 34 phosphoproteins and 29 protein spots. Castration decreased (P < 0.05) the abundance of two glycolytic enzymes of the energy-yielding phase, suggesting that glycolysis pathway enhanced glycerol-3P supply for a greater fat deposition on steers. Regarding the growth stage, despite the structural proteins myosin regulatory light chain 2 (MYLPF), and actin alpha 1 (ACTA1), most of identified proteins were related to energy metabolism, including glycogen metabolism, glycolysis, oxidative phosphorylation, creatine- phosphate metabolism, and cytosolic NADH metabolism. These results suggest that decreasing muscle growth rate decreases muscle glycolysis and ATP generation. The fourth study used only the twelve Nellore cattle harvested at 480 kg of BW. The aim of this study was to evaluate the differential proteome and phosphoproteome between bulls and steers during conversion of muscle to meat, as well as after 14 d of aging. Twelve male Nellore calves were used (247 kg, and 8 months old) and six calves were randomly selected for surgical castration one week before weaning. Post-weaning calves were fed the same diet and were harvested after 230 d on feeding. Longissimus muscle was sampled just after stunning (0d postmortem), at deboning (1d postmortem) and after aging (14d postmortem) for proteome analysis. The carcass traits were evaluated at deboning and meat shear force was measured at 1, 7, and 14 d postmortem. Muscle protein extract was separated by 2D-PAGE and stained sequentially for phosphoprotein (Pro-Q Diamond) and for total protein (Colloidal Coomassie). Differentially abundant protein spots between sex condition or across postmortem time were excised for protein identification by MALDI- TOF/TOF. Castration upregulated (P < 0.05) the abundance of glycolytic enzymes, while the oxidative phosphorylation protein ATP5B was downregulated (P < 0.05). In addition, abundance of troponin T fast isoform (TNNT3) was upregulated by castration (P < 0.05), while the slow isoform (TNNT1) tended to decrease (P < 0.10) abundance. The creatine kinase M-type was markedly fragmented postmortem. Abundance of phosphorylated PGM1 increased during the first 24 h postmortem and was highly correlated with carcass pH. The abundance of one spot of heat shock cognate 71 kDa protein (HSC70) markedly increased after aging. Further, abundance of the phosphorylated myofibrillar proteins ACTA1 and MYLPF were positively correlated with sarcomere shortening. In conclusion, our finds demonstrated that abundance and phosphorylation of glycolytic enzymes affect meat quality during conversion of muscle to meat. Overall, castration markedly increased carcass fatness and intramuscular fat, whereas whole body glucose sensitivity and conversion of muscle to meat seems to be similar between bulls and steers.
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(9778061), William Aspden. "Molecular and endocrine responses of the anterior pituitary gland and testes in male bovine treated with the Gonadotrophin releasing hormone Agonist Deslorelin." Thesis, 1998. https://figshare.com/articles/thesis/Molecular_and_endocrine_responses_of_the_anterior_pituitary_gland_and_testes_in_male_bovine_treated_with_the_Gonadotrophin_releasing_hormone_Agonist_Deslorelin/13463867.

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Project aims to determine "mechanisms of anterior pituitary gland function and testicular steroidogenesis which result in the increased testosterone secretion observed in male bovine treated with the GnRh agonist deslorelin".
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Books on the topic "Bovine males"

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Allchin, Douglas. Sacred Bovines. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190490362.001.0001.

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Some assumptions about biology are so deeply rooted in our thinking that they seem beyond question. These concepts - expressed in playful jargon - are our sacred bovines. With a light-hearted spirit, Douglas Allchin sets out to challenge many of these common beliefs about science and life. Allchin draws on fascinating insights from science to illustrate the ironies in many widespread beliefs. Be prepared to challenge the notion that male and female are fixed natural categories. Or that evolution implies cutthroat competition in human society. Or that we struggle against a fundamental immoral nature. Or that genes establish our identity. Or that science progresses through rare leaps of genius. Or that politics and emotions inevitably taint good science. Sacred Bovines revels in revelations about the nature of science. Reflecting on the many errors in commonly accepted, everyday ideas also fosters creative thinking. How do we challenge assumptions? How do we "think outside the box"? The many examples here provide inspiration and guidance, further elaborated in a retrospective epilogue. An additional "Afterword for Teachers" highlights how the essays can foster learning about the nature of science and describes some practical classroom strategies.
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Book chapters on the topic "Bovine males"

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Black, Samuel J., and Cynthia L. Baldwin. "Impact assessment of immunology and immunoparasitology research at ILRAD and ILRI." In The impact of the International Livestock Research Institute, 164–207. Wallingford: CABI, 2020. http://dx.doi.org/10.1079/9781789241853.0164.

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Abstract This book chapter assesses the research on bovine immunology and immunoparasitology conducted over 42 years, from 1973 to 2015, first at ILRAD (1973-1994) and subsequently at ILRI, which was formed by merging ILRAD and the International Livestock Centre for Africa (ILCA) in 1995. This assessment covers the approaches taken, the performance of research teams, the scientific truths uncovered, the cost-effectiveness of the research undertaken and the practical outcomes achieved, notably, the development of monoclonal antibodies (mAbs) and other tools to better define the bovine immune system. The chapter makes extensive use of citation data along with the personal reflections of scientists who participated in the research and surveys of opinion leaders in the field. The specific scientific goals and achievements of ILRI and its predecessors were as follows: making a substantive contribution to bovine immunology was realistic and has been substantially achieved, measuring the diversity of strains of Theileria parva, Trypanosoma brucei, Trypanosoma vivax and Trypanosoma congolense was realistic and has been substantially achieved, identifying mechanisms of immunity that kill parasites or limit the growth of the above parasites was realistic and has been substantially achieved, and developing an effective subunit vaccine against any of the parasites was an ambitious goal and so far has not been achieved.
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Allchin, Douglas. "Male, Female, and/ or — ?" In Sacred Bovines. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190490362.003.0024.

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Intersex individuals are coming out of the closet. Witness, for example, the 2003 Pulitzer Prize in Fiction for Jeffrey Eugenides’s Middlesex. The story follows someone with 5-alpha-reductase deficiency, or late-onset virilization. Imagine yourself raised as a girl, discovering at puberty (through cryptic, piecemeal clues) that you are male instead. Or male also? Or male only now? Or “just” newly virile? The condition confounds the conventionally strict dichotomy between male and female, masculine and feminine. It teases a culture preoccupied with gender. What are male and female, biologically? How does nature define the sexes, and sex itself? The questions seem simple enough. Seeking answers, however, may yield unexpected lessons—about the role of biological definitions; about assumptions concerning universals, rarities, and “normality”; and about the power of mistaken conceptions of nature to shape culture. Conceptualizing sex as male and female seems straightforward. In the standard version (familiar even to those unschooled in biology), females have two X chromosomes, while males have an X and a Y. They have different gametes: one moves, one stays stationary. These differences seem foundational. They seem to explain why male and female organisms have contrasting gonads, contrasting hormone-mediated physiologies, and contrasting secondary sex characteristics. Once-homologous organs follow divergent developmental trajectories. Perhaps even contrasting behaviors express the purported evolutionary imperative of each gamete: the “promiscuous,” uncaring male of cheap sperm, and the cunning, protective female of big-investment eggs. The apparent alignment of the two sexes through all levels of biological organization seems to validate this categorization as scientifically sound. Good biologists know better. First, sex may be determined in many ways. Birds use a “reversed,” WZ system, where females have the distinctive chromosome. Many insects have a haplodiploid system, where sex is determined by having a single or double set of all the chromosomes. Crocodiles and turtles develop their sex in response to temperature cues, not genes alone. The spoonworm Bonellia responds instead to whether females are absent or already present in the area.
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S. Kulkarni, Mrudula. "Mechanical Properties and Elasticity Model for Bovine Hard Tissue." In Bovine Science [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98410.

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This chapter aims at establishing engineering material properties of bovine hard tissue cut out of long bone. The study and design of implants, medical devices, and their bone material necessitate the knowledge of mechanical properties of bone to be evaluated. Braces or steel plates are used as fixation devices in animals who are treated for the fracture to bone or cracked bone. Braces or steel plates are fixed to the bone by rods and screws. For checking the stability of these inserted metallic parts, they have to be compatible with bone. The metal and bone form composite action for the load transfer mechanism. To ensure proper biomechanics and design of these inserts and accessories, we need to know the elastic properties of bone. This chapter establishes the modulus of elasticity, poisons ratio of Bovine femur bone. The experimental study establishes the orthotropic behavior of Bovidae femur bone. This experimental research provides comprehensive mechanical properties of Bovidae femur bone, through series of mechanical tests. By performing compression tests on a bone specimen, stress, strain, elastic modulus, poison’s ratio, and yielding point of bone are established. The bovine long bone exhibits orthotropic or transversely isotropic nature of femur bone as expected. The data presented here is for samples derived from goat and water buffalo. The solid mechanics approach using stiffness matrix is adopted to establish elastic constants. The data of elastic constants, compliance, and stiffness coefficients obtained can be used for finite element analysis to simulate stability of composite, femur bone, and metallic fixation. The values of compression strength, Young’s modulus, Poisson’s ratio, and shear modulus are higher for water buffalo male than that of female showing gender difference. This may be attributed to lower bone density in females due to hormone secretion.
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Allchin, Douglas. "A More Fitting Analogy." In Sacred Bovines. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190490362.003.0013.

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In our culture no one needs a biology class to learn about “survival of the fittest.” Yet one might need instruction to unlearn the misconceptions engendered by the analogy’s potent imagery. In popular perspectives, this single phrase conjures images of humans—however civilized—as brutish organisms vying for jobs, status, and power. Maybe they also compete for prime mates. The language of “survival” resonates with “survivor” contests on television: “Outwit. Outplay. Outlast.” Mention of the “fittest” implies that physical “fitness” and athletic prowess are ideals. At the same time, the extremeness of reference to only the “fittest” implies that a human’s fate seems to be life versus death, fit versus unfit, winning versus losing. In all, cooperation and coexistence give way to warfare, conflict, and backstabbing gossip: “society, red in tooth and claw,” to adapt Tennyson’s phrase. Mostly, life reduces to competition. Cutthroat competition. Through just one expression, all these interpretations seem to have a biological basis. None of them are scientifically justified. “Survival of the fittest” is not a neutral phrase, idly describing natural selection. Instead, through unintended metaphors the language fosters major misconceptions. One might hope to remedy these many confusions. But how? “Survival of the fittest” seems to describe both organic evolution and human culture. So first, one must carefully distinguish the processes of each, functioning at different levels (essay 6). Second, one needs to understand how ideology can be unduly naturalized (or improperly inscribed in “nature”). The phrase was never purely descriptive. It expressed cultural values (essay 7). Even with both these pitfalls resolved, however, problems may persist because of the very language itself. The connotations of the phrase seem inescapable. Here, I consider the misconceptions latent in each individual term: “survival” and “fit”—as well as the “-est” suffix. That may help us craft a more fitting analogy or catchphrase to describe natural selection. Consider first the implications of the word “survival.” What matters to evolution is differences in survival rate at a population level. Differential survival leads to differential reproduction, the essence of natural selection.
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Allchin, Douglas. "A Comedy of Scientific Errors." In Sacred Bovines. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190490362.003.0016.

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William Shakespeare may well have foreshadowed the modern television sitcom. His comic misadventures were expertly crafted. In A Comedy of Errors, for example, twins with twin servants, each pair separated at birth, converge unbeknownst to each other in the same town. Mistaken identity leads to miscommunication. More mistaken identity follows, with more misdelivered messages and yet more misinterpretations. Hilarious consequences ensue. It is a stock comedic formula in modern entertainment: A character first makes an unintentional error. Then ironically, as he tries to correct it, things only get laughably worse. Science, we imagine, is safeguarded against such embarrassing episodes. In the lore of scientists, echoed among teachers, science is “self-correcting.” Replication, in particular, ensures that errors are exposed for what they are. Research promptly returns to its fruitful trajectory. Serious stuff, science. But just such a case of compounded error occurred in late eighteenth-century science. Joseph Priestley (Figure 10.1) discovered that plants can restore the “goodness” of air that had been fouled by animals or combustion. But others could not replicate his results. Not even Priestley himself. After further work, Priestley attributed the observed restorative effect to a different causal factor—only to find later that the new conclusion itself was mistaken! For us now, the story seems amus­ing, but nonetheless instructive. The case invites us to reconsider the sacred bovine that science is self-correcting, and especially that replication is central to exposing errors. Indeed, this reassessment leads us deeper into reflecting on our romantic idealizations of science, an enduring legacy of Priestley’s Enlightenment period, centuries ago. The story begins in the early 1770s, in Leeds, England. Joseph Priestley—minister, avid experimentalist, and self-taught chemist—had been investigating various kinds of air. At this time, he was examining various ways of making air noxious: by the putrefaction of dead mice or cabbage, by burning charcoal in it, by mice breathing it, or by candles burning out in it (all processes that exhaust the oxygen, in today’s terms).
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Allchin, Douglas. "Hands- Off Dissection?" In Sacred Bovines. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190490362.003.0036.

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Amid the mantra-like rhetoric of the value of “hands- on” learning, the growth of computer “alternatives” to dissection in biology education is a striking anomaly. Instead of touching and experiencing real organisms, students now encounter life as virtual images. Hands-on, perhaps, but on a keyboard instead. Or on a computer mouse, not the living kind. This deep irony might prompt some to hastily redesign such alternatives. Or to find and adopt others. However, one could—far more deeply and profitably—view this as an occasion to reflect on the aims in teaching biology. What do computer programs and models teach? By not sacrificing any animal, one ostensibly expresses respect for life. Nothing seems more important—or moral—for a biology student to learn. Yet using this standard—respect for life—many alternatives to dissection seem deeply flawed. First, most alternatives share a fundamental destructive strategy of taking organisms apart. Each organ is removed and discarded in turn. That might seem to be the very nature of dissection. Yet some contend that “the best dissection is the one that makes the fewest cuts.” Here, the aim is discovery, not destruction. One tries to separate and clarify anatomical structures: trace pathways, find boundaries, encounter connections—quite impossible if things are precut and disappear as preformed units in a single mouse click. The “search and destroy” strategy, once common, is now justly condemned. Such dissections were never well justified. They reflect poor educational goals and fundamentally foster disrespect toward animals. Indeed, dissections may be opportunities to monitor and thus guide student attitudes. Search-and-destroy alternatives to dissection merely echo antiquated approaches. Better no dissections at all than such ill-conceived alternatives. Second, prepackaged images or take-apart models are not much better. They reduce the body to parts. No more than pieces in a mechanical clock. They neatly parcel the body into discrete units. However, a real body is messy. It is held together with all sorts of connective tissue.
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Allchin, Douglas. "Science Con Artists." In Sacred Bovines. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190490362.003.0022.

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Deception abounds in nature. Some species are first-rate con artists. Anglerfish with appendages that mimic squiggling morsels to lure unsuspecting prey. Carnivorous pitcher plants that emit the aroma of rotting flesh and attract flies to their doom. Orchids that resemble female wasps, decoys for male wasp pollinators. Cuttlefish whose color and pattern change with the background as a disguise against predators. Deceptive patterns, smells, or sounds in organisms wonderfully reflect the adaptive response to opportunity. So, too, in human culture? Humans can take advantage of cultural conditions and deceive others to promote their own interests. So if science receives cultural authority, it should surprise no one that those seeking power or profit might try to mimic it. Indeed, the more authority we give to science, the greater the likelihood of science impostors—and the more sophisticated their deceptive tactics. Cultural anthropologist Chris Toumey likens the process to a magician’s illusions. Imitators “conjure” science, he says, “from cheap symbols and ersatz images.” It is an apt and vivid label. We could just as easily call them science con artists (Figure 15.1). Liars. Cheats. Predictable opportunists who seek our confidence using a semblance of science. Many proponents of science endeavor to inform citizens and consumers so that they do not succumb to such wiles. The typical posture, too easily adopted I think, is that simple knowledge of the scientific method or of how to evaluate scientific evidence will suffice. By learning about what defines science and what pseudoscience, one supposedly is empowered to debunk the charades. Yet one may well question this sacred bovine. A sampling of recent historical cases may indicate how prevalent science con artists are in modern society. They are far more significant than commonly assumed. Science and what counts as science publicly can diverge sharply (essay 13). Specific skills may help one sort experts from nonexperts (essay 14). But con artists use various psychological stratagems to gain trust by bypassing questions of expertise.
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SAOUD, M. F. A. "HERMAPHRODITIC MALES OF SCHISTOSOMES WITH PARTICULAR REFERENCE TO SCHISTOSOMA BOVIS." In Proceedings of the First International Congress of Parasitology, 742–43. Elsevier, 1999. http://dx.doi.org/10.1016/b978-0-08-011427-9.50106-2.

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Adesanya, Adetayo, and Victor Adesanya. "A Laboratory-Scale Study: Biodegradation of Bisphenol A (BPA) by Different Actinobacterial Consortium." In Actinobacteria - Diversity, Applications and Medical Aspects [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.105546.

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The unique diversity of microbes makes them ideal for biotechnological purposes. In this present study, 16 actinobacterial isolates were screened on media supplemented with Bisphenol A (BPA). Three out of 16 isolates exhibited high biocapacity to degrade BPA as a carbon source. Four different mixed actinobacterial consortia were developed using the above strains and the effect of each consortium on biomass growth; laccase production and BPA degradation were examined. At 100-mg/L BPA concentration, the three-member consortium grew well with maximum laccase activity as well as maximal degradation rate of Bisphenol A than the other two-member consortium. The consortium of Actinomyces naeslundii, Actinomyces bovis, and Actinomyces israelii degraded 93.1% with maximum laccase activity of 15.9 U/mL, followed by A. naeslundii and A. israelii with 87.3% and 9.5 U/mL. This was followed by A. naeslundi and A. bovis with 80.4% and 8.7 U/mL, while A. bovis and A. israelii degraded 76.0% with laccase activity of 7.0. The gas chromatography–mass spectrometry (GC–MS) analysis of biodegraded BPA showed the presence of oxalic acid and new products like 1,2,4-trimethylbenzene and 2,9-dimethyldecane.
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Sánchez Dávila, Fernando, and Gerardo Pérez Muñoz. "Reproduction in Small Ruminants (Goats)." In Animal Reproduction in Veterinary Medicine [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.93481.

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The exploitation of small ruminants (goat and sheep) has always been linked to the development of human civilizations, where they have mainly fed on their derived products such as milk and meat. Currently, the sheep population is around 1 billion head concentrated above 50% in three countries, China, Australia, and New Zealand, contrary to goats with around 720 million heads, distributed mainly in Asia, Africa, and South America. Both species have similar characteristics in some anatomical aspects (a pair of nipples), gestation period (150 days), and presence of seasonal anestrus, differing in terms of magnitude and depth and presence of the male effect. However, they are completely different in feeding habits, nutrient needs, and grazing systems, with differences in terms of the female’s reproductive tract, among other characteristics. Currently, the study of reproduction has intensified over the years in the goats and its counterpart that is the buck. Therefore, in the following topics, the importance of global reproduction of the goat will be discussed, considering that progress has been made today in the application of third generation reproductive techniques and that today they are already consolidated and developed in the bovine species.
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Conference papers on the topic "Bovine males"

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LOREDO NETO, Francisco Antonio, Gabriela Santos FREITAS, Raquel Varella SERAPIÃO, Leticia Patrão GOMES, and Thiago Luiz Pereira MARQUES. "ANALYSIS OF THE SEXUAL BEHAVIOR OF BULLS OF THE TABAPUÃ BREED." In SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 2021 INTERNATIONAL VIRTUAL CONFERENCE. DR. D. SCIENTIFIC CONSULTING, 2022. http://dx.doi.org/10.48141/sbjchem.21scon.43_abstract_loredo.pdf.

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Beef cattle is one of the main sectors that drive the national economy, given the great generation of employment, presence in the consumer market, and exports. Among the various services generated, technical assistance to producers stands out, who work in several areas and, especially reproduction, which is a great ally to bovine production, because through it it is possible to monetize the creation with the use of reproducers with high fertility potential boosting livestock productivity. Therefore, the andrological evaluation in the sires is an important factor in selecting superior animals, seeking to improve the fertility of the herd. The present study aimed to analyze the sexual behavior of bulls of the Tabapuã breed, through the libido test, as part of the andrological examination. Ten young bulls of the Tabapuã breed were used, aged between 24-43 months, with an average weight of 375kg, without sexual experience. The libido test was performed from the contact of males with females in estrus and out of estrus to assess sexual interest. It was observed that half of the animals were classified with low libido (50%) and the other part with medium (30%) and high (20%) libido. In addition, it was observed that the most frequent sexual events were the identification of estrus. Finally, given the results of animals classified with low libido, it is suggested that sexual inexperience is correlated, and it is recommended to insert these cattle with high libido bulls so that they can observe the behaviors and gain experience.
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Ramzanpour, Mohammadreza, Mohammad Hosseini-Farid, Mariusz Ziejewski, and Ghodrat Karami. "Particle Swarm Optimization Method for Hyperelastic Characterization of Soft Tissues." In ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-11829.

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Abstract Hyperelastic constitutive models such as Ogden and Mooney-Rivlin are commonly used for nonlinear characterization of soft materials and especially biomaterials such as brain tissue. The parameters of these models are usually found by curve-fitting to the experimental or in some cases, the numerical data. Most of the times, common non-linear least square curve fitting method known as Levenberg-Marquardt (LM) is employed for this purpose. In this paper, we show that the result of this method is highly dependent to the initial guesses. In some cases, the approximated curve-fitting solution can be very close to the experimental data, however, the hyperelastic parameters can be very different to the actual ones despite the fact that a very good curve-fitting solution (high coefficient of correlation) may be achieved. To overcome this problem, we demonstrate the application of a derivative free (black box) optimization method called particle swarm optimization (PSO) for hyperelastic characterization of nonlinear materials using least square method. Using multiple search agents in PSO makes this method highly inclined to end up with global optimum points in the search space. In this study, the hyperelastic parameters for Ogden and Mooney-Rivlin hyperelastic models are found for bovine brain tissue by using the experimental uniaxial compression test data. The PSO method yields high coefficient of correlation for curve fitting and its results is comparable to the LM method in terms of accuracy of parameters. It is concluded that PSO can be successfully used for nonlinear hyperelastic characterization of soft materials such as brain tissue.
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Yeung, Edward S., Wei Tong, and Sheri Lillard. "Cell Imaging by Laser-Induced Native Fluorescence Microscopy." In Laser Applications to Chemical and Environmental Analysis. Washington, D.C.: Optica Publishing Group, 1998. http://dx.doi.org/10.1364/lacea.1998.lma.2.

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The high degree of heterogeneity of the nervous and endocrine systems makes it extremely important for real-time monitoring of dynamic chemical changes at the single-cell level to gain a better understanding of the interaction of cells with their environment. Secretion mediated by exocytosis is one of the fundamental phenomena whose mechanism mimics the release of neurotransmitters at synaptic sites. Although the regulation of the secretory pathway has been studied extensively, its molecular mechanism is still not clear. It is important to develop methods that can follow real-time secretory processes with both high temporal and high spatial resolution. The native fluorescence of some proteins and neurotransmitters excited by a deep-UV laser has been shown to be a powerful probe for single-cell analysis. The advantages of direct native fluorescence detection include: (1) no chemical derivatization with fluorescent dyes is needed so no contamination or additional background will be introduced; (2) uncertainties about the efficiencies of the derivatization reaction are eliminated to ensure fast and quantitative response, without influences from slow reaction kinetics or incomplete equilibrium; and (3) the biological integrity of the cells will not be unnecessarily disturbed by having additional reagents or from exposure to artificial environments. We report the coupling of laser-induced native fluorescence detection with capillary electrophoresis (CE) to quantitatively monitor the secretion of insulin, serotonin and catecholamines from single cells. The uptake of serotonin by single living astrocytes was also recorded by native fluorescence imaging microscopy. The catecholamine (mainly epinephrine and norepinephrine) secreting adrenal chromaffin cells have been used as “model nerve terminals” to elucidate the molecular mechanism of neurotransmitter secretion at the nerve terminal. The in vitro dynamics of catecholamine release from bovine adrenal chromaffin cells was monitored with both high spatial and high temporal resolution.
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Lobel, P., M. Palmer, and K. Schor. "CHRONIC ORAL DEFIBROTIDE STIMULATES VASCULAR PGI2 AND INHIBITS ATHEROSCLEROTIC PLAQUE FORMATION IN CHOLESTEROL-FED RABBITS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643150.

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Defibrotide (DEF) is a polydeoxyribonucleotide fraction from bovine lung, possessing profibrinolytic and PGI2 stimulating properties. Male rabbits were fed for 4 months a standard laboratory diet (150 g/day) without (A) or with (B) DEF or a cholesterol (1%) supplemented diet without (C) or with (D) DEF (60 mg/kg x day) was administered orally (drinking water) and withdrawn 24-36 h prior to the acute experiments.DEF did not change the elevated serum cholesterol: 18 ± 2 (C) vs. 26 ± 5 (D) mM but significantly reduced the plaque formation in the aorta from 4.5 ± 0.3 (C) to 3.3 ± 0.2 (D) (subjective score). Collagen induced (0.6 pg/ml) thromboxane formation and ATP release was significantly reduced by DEF: 55+2 (C) vs. 42 ± 2 (D) ng/ml TXB2; 152 ± 11 (C) vs. 74±5 (D) AU ATP (platelet rTch plasma). DEF significantly increased the basal and bradykinin (Bk, 30 nM) stimulated PGI2 release from rabbit aorta preparations in Krebs buffer, while the PGI2 forming capacity (arachidonic acid, AA, 30 pg/ml) was unchanged Furthermore, the iloprost (30 nM) stimulated cAMP was significantly elevated by DEF in both control: 115 ± 10 (A) vs. 155 ± 18 (B) pmoles/1 and cholesterol-fed rabbits: 120 ± 14 (C) vs. 172 ± 9 (D). DEF, directly added to the platelets in vitro did not inhibit platelet activation up to 100 pg/ml.The data demonstrate a 2-3-fold stimulation of basal and hormone (Bk) induced PGI2 formation of control and sclerotic rabbit aorta after 4 months DEF treatment while the atherosclerosis per se does not significantly change these parameters. DEF treatment also significantly reduces platelet hyperreactivity at unchanged serum ch() lesterol. Both properties might be useful to prevent complication’s of atherosclerosis, such as myocardial infarction and stroke.
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Holmes, W. E., H. R. Lijnen, and D. Collen. "CHARACTERIZATION OFα2-ANTIPLASMIN.REACTIVE SITE VARIANTS PRODUCED BY SITE-DIRECTED MUTAGENESIS." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644766.

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α2-Antiplasmin (α2AP) is the primary physiological plasmin inhibitor in human plasma. The inhibition is rapid (second order rate constants (k1) are expressed as M−1 s−1 ) (k1 = 2 × 107) and occurs as the consequence of an irreversible 1:1 stoichiometric complex formation; the exact nature of and the forces involved in complex formation are not fully understood. In fact, what makes α2AP an inhibitor, rather than simply a substrate remains unresolved. Recently, we deduced the primary structure of α2 AP from the sequence of its cDNA. 95%of this sequence was confirmed by amino acid (aa) sequence analysis of naturalα2 AP (α2 AP)? The 452 aa molecule contains 2 disulfide bonds and 4 glycosylated Asn residues, aa sequence alignment confirmed α2AP's membership in the Serpin family. The reactive site sequence as determined by NH2 - and COOH-terminal aa sequence analysis of the plasmin-modified inhibitor and the released M−r ∼ 8000 peptide is Met362-Ser363-Arg364-Met365-Ser366, P3-P2-P1-P'1-P'2, respectively.Natural and engineered P1 residue substitutions in the Serpin α2 -antitrypsin ( α2 AT) have shown altered specificities and efficiencies. To further examine the role of P and P' residues in determining Serpin specificity, in the present study we have by site-directed mutagenesis, deleted (△) the P'l-Met365 residue of a AP thereby producing a recombinant (r) inhibitor (r α2 AP△Met365) whose putative new reactive site mimics that of antithrombin III (ATIII) and a AT-Pittsburgh (Pl-Arg-P'1-Ser). A second variant was constructed (ra2AP△Arg364) in which the Pl-Arg364 residue was deleted, producing the new sequence Met362-Ser363-Met364-Ser365, containing 2 potential sites analogous to the Pl-P'l, Met-Ser reactive site of α2 AT. The variants and r α2 AP were expressed in CH0 cells, purified and compared with n α2 AP, α2AT and ATIII for the ability to inhibit plasmin, thrombin, trypsin and elastase. n α2 AP and r α2 AP had nearly identical inhibition constants and like ATIII did not inhibit neutrophil elastase. Without heparin both α2 APs and ATIII inhibited thrombin moderately (k1 = 2 to 4× 103 ). Bovine trypsin was neutralized by the α2 APs with k1 = 3 × 106 and by ATIII with k1 = 1 × 105. The α2APs inhibited plasmin (k1 = 2 ×107 ) much more efficiently than ATIII (K1 =2 × 103 ). In contrast, was a highly effective antielastase (k1 = 1 × 107 ), a poor plasmin and thrombin inhibitor ancl inhibited bovine trypsin with = 2 × 10. As reported by others, α2 AT-Pittsburg has greatly reduced antielastase activity and greatly enhanced antithrombin activity. Analysis of ra APAMet365 revealed little change in activity toward plasmin, trypsin and elastase. Thus, α2 AP has no absolute requirement for Met .in the P'l position in order to effectively inhibit plasmin and trypsin. The other P^ subsites appear to be spatially flexible as deletion of the natural P'l residue must displace them. Contrary to prediction a 20-fold decrease in antithrombin activity was observed rather than an enhanced activity. Analysis of rα2 AP△Arg364 showed that it is unreactive with plasmin, trypsin and thrombin, but that it has acquired a significant antielastase activity (k1 = 1.5 × 105). The exact PI residue(s) has not been determined but removal of the bulky basic Arg364 may have resulted in accessibility of the predicted reactive site(s) peptide bond(s) Met362-Ser363 or Met364-Ser365 to the active site cleft of elastase. α2AP'Enschede', a natural mutant with deficient antiplasmin activity, was shown to contain an Ala insertion between aa 353 and 357, 7 to 10 positions NH2-terminal to its reactive site (Holmes et al., this meeting). This mutation results in conversion of α2 AP'Enschede' from an inhibitor to a substrate that retains a high affinity for the active site of plasmin.
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