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1.
J Vet Med Educ ; : e20220072, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36706018

RESUMO

A review of current literature provides ample evidence that Student Evaluation of Teaching, as currently practiced, can be a biased and flawed evaluation of educator performance and student learning. Due to this, many institutions have developed their own internal multimodal approach for faculty evaluation and professional advancement review that removes the underlying bias associated with survey results. Ross University School of Veterinary Medicine created a taskforce to evaluate the current teaching assessment practices and provide an alternative method. Based on an extensive literature review, an institutional policy was created using a multimodal approach, combining student evaluations of teaching scores with peer review of teaching, review of teaching materials, mentorship, self-ratings, and self-reflection. The implementation plan for this policy is described to allow for a teaching evaluation process built on a philosophy of mentorship, guidance, and self-reflection; as well as the use of external professional exam metrics to review the institutional academic quality at large.

2.
J Dairy Sci ; 102(4): 3754-3765, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30772031

RESUMO

Diseases of postpartum dairy cows impair reproductive processes, resulting in prolonged anestrus, reduced conception, and increased pregnancy attrition, regardless of whether the initial disease precedes insemination (even by many weeks), occurs close to insemination, or follows fertilization. Bacteria and their products activate pattern recognition receptors that respond to pathogen-associated molecular patterns (PAMP). These receptors include toll-like receptors (TLR), nucleotide-binding oligomerization domain (NOD)-like receptors and others, and their activation culminates in upregulation of proinflammatory cytokines such as IL-1ß, IL-18, and tumor necrosis factor-α. These may have direct effects on the uterus and conceptus. Importantly, however, these inflammatory mediators, as well as the bacterial products, make their way to the ovary via the general circulation (even from distant sites) or possibly by using the countercurrent vascular mechanism that normally transports endometrial prostaglandin to the ipsilateral ovary. Endotoxin reaches concentrations in follicular fluid that exceed those found in the circulation or even in the infected uterus. Ovarian follicular cells also express TLR and can respond directly to bacterial products including endotoxin, impairing their function. Inflammation is accompanied by increased oxidative stress. The process of oocyte development from activation of primordial oocytes to potential ovulation spans 4 mo. Competence by an oocyte encompasses the ability to undergo not only fertilization but also a complex cytoplasmic maturation that lays the foundation for completion of meiosis at the appropriate time, the transition to mitosis in the zygote, and further development of the conceptus. Oocyte maturation relies on intimate association between cumulus cells and the oocyte, characterized by gap junctions through which molecules of various sizes pass. Signaling also occurs in the oocyte-to-cumulus cell direction. Because both granulosa and theca interna cells are capable of responding to inflammatory mediators, with observed alterations in some functions, it seems likely that disturbed ovarian follicular function may contribute to failure of oocytes to become fully competent, even if the insult occurs well before ovulation. Therefore, interruption of normal fertility by uterine infections may be mediated at the level of the uterine environment but the effect on the ovary and oocyte is likely to be even more important.


Assuntos
Infecções Bacterianas/veterinária , Doenças dos Bovinos , Infertilidade Feminina/veterinária , Transtornos Puerperais/veterinária , Infecções do Sistema Genital/veterinária , Animais , Infecções Bacterianas/complicações , Bovinos , Doenças dos Bovinos/microbiologia , Feminino , Fertilidade/fisiologia , Fertilização/fisiologia , Líquido Folicular , Infertilidade Feminina/microbiologia , Oócitos/fisiologia , Folículo Ovariano/fisiopatologia , Ovário/fisiopatologia , Ovulação , Gravidez , Transtornos Puerperais/microbiologia , Infecções do Sistema Genital/complicações , Infecções do Sistema Genital/microbiologia
3.
Proc Natl Acad Sci U S A ; 112(17): 5431-6, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25870286

RESUMO

Successful mammalian reproduction requires that sperm migrate through a long and convoluted female reproductive tract before reaching oocytes. For many years, fertility studies have focused on biochemical and physiological requirements of sperm. Here we show that the biophysical environment of the female reproductive tract critically guides sperm migration, while at the same time preventing the invasion of sexually transmitted pathogens. Using a microfluidic model, we demonstrate that a gentle fluid flow and microgrooves, typically found in the female reproductive tract, synergistically facilitate bull sperm migration toward the site of fertilization. In contrast, a flagellated sexually transmitted bovine pathogen, Tritrichomonas foetus, is swept downstream under the same conditions. We attribute the differential ability of sperm and T. foetus to swim against flow to the distinct motility types of sperm and T. foetus; specifically, sperm swim using a posterior flagellum and are near-surface swimmers, whereas T. foetus swims primarily via three anterior flagella and demonstrates much lower attraction to surfaces. This work highlights the importance of biophysical cues within the female reproductive tract in the reproductive process and provides insight into coevolution of males and females to promote fertilization while suppressing infection. Furthermore, the results provide previously unidentified directions for the development of in vitro fertilization devices and contraceptives.


Assuntos
Colo do Útero , Tubas Uterinas , Fertilidade/fisiologia , Motilidade dos Espermatozoides , Espermatozoides , Tritrichomonas foetus/metabolismo , Aborto Animal/metabolismo , Aborto Animal/patologia , Animais , Bovinos , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/patologia , Colo do Útero/anatomia & histologia , Colo do Útero/fisiologia , Tubas Uterinas/anatomia & histologia , Tubas Uterinas/fisiologia , Feminino , Masculino , Infecções por Protozoários/metabolismo , Infecções por Protozoários/patologia
4.
Trop Anim Health Prod ; 50(5): 1171-1173, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29430608

RESUMO

Trichomonosis is an endemic disease in cattle that are reared under extensive conditions and bred by natural mating. It causes profound economic losses to the producers by increasing calving interval, increasing embryo losses, and decreasing pregnancy rates. The aim of this study was to determine whether Tritrichomonas foetus infections were absent from cattle in St. Kitts. Using the modified hypergeometric method, preputial samples from bulls (n = 78) were tested using the InPouch™ culture for presence of T. foetus. Results highlighted an absence of trichomoniasis in bulls on St. Kitts with a 95% confidence.


Assuntos
Doenças dos Bovinos/epidemiologia , Infecções Protozoárias em Animais/epidemiologia , Tritrichomonas foetus , Animais , Bovinos , Feminino , Masculino , Gravidez , Infecções por Protozoários , São Cristóvão e Névis/epidemiologia
5.
Biol Reprod ; 94(1): 18, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26632612

RESUMO

Most dairy cows develop the first dominant follicle postpartum within 2 wk after calving, but only about 40% of these follicles produce sufficient estradiol to stimulate ovulation despite having normal ultrasound appearance and growth. This study aimed to characterize metabolic, endocrine, and follicular fluid profiles of cows in which the first dominant follicle postpartum will become ovulatory and those with nonovulatory follicles. Luteinizing hormone pulse frequency, follicular fluid androstenedione, and follicular fluid estradiol concentrations were lower in nonovulatory cows suggesting that the function of theca cells is impaired. In addition, nonovulatory cows had more severe negative energy balance and greater insulin resistance postpartum. This study describes for the first time the steroid hormone profile of early postpartum follicles and shows that a steroidogenic defect most likely occurs in theca cells limiting the amount of androgen precursor available for estradiol production that impairs their ovulatory outcome.


Assuntos
Folículo Ovariano/fisiologia , Ovulação/fisiologia , Período Pós-Parto/fisiologia , Androstenodiona/metabolismo , Animais , Metabolismo dos Carboidratos , Bovinos , Metabolismo Energético , Estradiol/metabolismo , Feminino , Fertilidade , Líquido Folicular/metabolismo , Teste de Tolerância a Glucose , Resistência à Insulina , Hormônio Luteinizante/sangue , Proteínas/metabolismo , Células Tecais
6.
Can Vet J ; 55(5): 462-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24790232

RESUMO

Two late gestation Holstein cows about to begin the third lactation developed massive vulvar edema. These were the only affected animals in the herd of 500 milking cows. The vulvar edema spontaneously regressed postpartum for both cows. Massive vulvar swelling is seldom observed in dairy cows in advanced pregnancy and is not described in the literature.


Edème vulvaire massif chez deux vaches laitières prépartum. Deux vaches Holstein en fin de gestation s'apprêtant à commencer la troisième lactation ont développé un œdème vulvaire massif. Il s'agissait des seuls animaux touchés dans le troupeau de 500 vaches laitières. L'œdème vulvaire a spontanément régressé postpartum pour les deux vaches. L'enflure vulvaire massive est rarement observée chez les vaches laitières aux stades avancés de la gestation et elle n'est pas décrite dans la littérature.(Traduit par Isabelle Vallières).


Assuntos
Doenças dos Bovinos/patologia , Edema/veterinária , Doenças da Vulva/veterinária , Animais , Bovinos , Doenças dos Bovinos/sangue , Edema/sangue , Edema/patologia , Estradiol/sangue , Feminino , Período Periparto , Gravidez , Progesterona/sangue , Doenças da Vulva/sangue , Doenças da Vulva/patologia
7.
Trop Anim Health Prod ; 44(7): 1567-73, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22395793

RESUMO

The aim of this study was to evaluate the effect of postpartum mastitis between first calving and subsequent conception on production and reproduction performance as well as culling of Holstein cows. A data set of 9,183 first lactation cows was used. Results showed that the first cumulative 100 days' milk production and the milk yield standardized to 305 days were affected by the interval from calving to first mastitis (P < 0.05). Cows with one episode of mastitis produced more milk than those with repeated episodes of mastitis (P < 0.01). Increase in the number of mastitis episodes and also decrease in interval between first calving and mastitis increased services per conception (P < 0.001). Mastitis episode and the interval between calving and first mastitis had no apparent impact on the calving to conception interval (P > 0.05). Calving year, calving difficulty score, and cumulative first 60 days milk production had significant impacts on mastitis risk (P < 0.05). The interval from calving to the first incidence of mastitis decreased over the period studied (P < 0.001). Productive life tended to be decreased due to mastitis (P = 0.07). Survival analysis showed a significant difference between the lengths of productive life for cows with different intervals from calving to first mastitis (P < 0.01). The results demonstrated that clinical mastitis between first calving and conception reduced production and reproduction performance with an increase in chance of culling.


Assuntos
Fertilização , Lactação , Mastite Bovina/epidemiologia , Reprodução , Animais , Bovinos , Indústria de Laticínios , Feminino , Incidência , Irã (Geográfico)/epidemiologia , Mastite Bovina/diagnóstico , Mastite Bovina/microbiologia , Leite/microbiologia , Paridade , Período Pós-Parto , Análise de Regressão , Análise de Sobrevida
8.
Animals (Basel) ; 12(4)2022 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-35203165

RESUMO

The overpopulation of donkeys is recognized as a problem in many parts of the world. The main concerns with uncontrolled donkey populations are habitat degradation and competition for feed resources between donkeys and other species. One of the most effective and humane solutions is the use of immunocontraception. Therefore, this study sought to evaluate the stress imposed by the use of two formulations of a zona pellucida (ZP) vaccine, a recombinant (reZP) and a native porcine (pZP) vaccine, both formulated with a Freund's adjuvant. The stress was objectively measured using fecal cortisol concentrations and physical examination parameters at fixed points before and after vaccination. We hypothesized that fewer changes in physical exam parameters and lower fecal cortisol concentrations would be stimulated in jennies treated with the reZP vaccine due to the selection of specific proteins. Twenty-five reproductively sound jennies were randomly assigned to reZP (n = 9), pZP (n = 8) or control (n = 8) groups. The vaccines were administered at five-week intervals. Physical exam parameters and body wall thickness of injection sites were recorded for each jenny for four days post-injections. Fecal samples were obtained every other day from day 0 (first vaccination) through day 6 and on days 35 to 41 after booster. Injection site reactions were common in all groups with the reZP and pZP groups being overrepresented. Lameness was observed in the pZP and reZP groups that were affected by injection site reactions and open abscesses. The present study showed an increase in fecal cortisol concentrations within 4 days after the first vaccination with ZP vaccines and, thereafter, a decrease in cortisol 35 days later after the second vaccination, especially in donkeys with open abscesses. Our results suggest that acute stress (increased cortisol) was induced after the first vaccination, and chronic stress (decreased cortisol) occurred thereafter in association with open abscesses. In conclusion, reZP and pZP formulated with Freund's adjuvant induced local inflammatory reactions with a differential degree of acute and chronic stress in donkeys.

9.
Animals (Basel) ; 12(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35049751

RESUMO

We aimed to characterize early embryo development and changes in corpus luteum (CL) development and progesterone profile in pregnant vs. non-pregnant jennies. Eight jennies were enrolled in the study. In the first two cycles, the jennies were monitored by transrectal ultrasonography and had blood harvested for hormone profile assay. In the third cycle, jennies were bred by a jack of proven fertility. Jennies were then monitored and sampled for up to 30 days of pregnancy. Data were evaluated by random-effects multiple linear regression, and correlations were expressed as Pearson's correlation coefficient. Progesterone concentration rose rapidly from ovulation (D0) until D7, plateaued until D12-14, then precipitously declined between D14 and 15, remaining low until the next ovulation in non-pregnant cycles. In the pregnant jennies, the progesterone concentration rose to maximal concentrations on D7-11, being higher at this stage than in non-pregnant cycles, then declined gradually up to D30. In all cycles, the volume of the CL increased steadily until D6, when it plateaued in pregnant jennies. For non-pregnant jennies, CL volume decreased slowly from D6 to D11 and then had a faster drop. Uterine tone increased following ovulation, becoming turgid around the day of embryo fixation (D15.0 ± 0.9). An embryonic vesicle (EV) was first detected on D9.3 ± 0.5 (2.4 ± 0.5 mm). The EV remained spherical until D18.6 ± 1.4. The embryo proper was first detected ventrally in the vesicle on D20.8 ± 1.1 and the embryonic heartbeat by D22.0 ± 0.9. The allantoic sac was identified at D24.0 ± 0.9, and at D30, the allantoic sac filled the ventral half of the EV. This study provides evidence that higher cumulative concentrations of progesterone are correlated to size of the EV, and there were changes in the luteal dynamics and progesterone profiles in pregnant vs. non-pregnant jennies.

10.
Animals (Basel) ; 13(1)2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36611684

RESUMO

Eight non-bred, non-pregnant, regularly cycling Caribbean jennies were examined daily via transrectal ultrasound to define the ovarian and uterine dynamics during four consecutive estrous cycles. Blood samples were collected every other day for progesterone analysis. The mean (±SD) overall inter-ovulatory interval across all donkeys and cycles was 22.93 ± 1.99 days. The maximum follicular diameter was 34.6 ± 2.9 mm. A two-wave pattern was evident in 97% (30/31) of the cycles. The emergence of the future dominant follicle and the largest subordinate follicle of the major primary wave coincided on Day 5.7 ± 3.6 post-ovulation, whereas the secondary wave emerged on Day 19.8 ± 2.9 during estrus of the previous cycle or early diestrus. The secondary wave was often minor (93%, 28/30 cycles). Follicular deviation occurred 8.2 ± 1.4 days before the subsequent ovulation. Luteal volume increased for the first four days after ovulation and reached a maximum volume of 8.5 ± 2.7 mm3 at Day 5.4 ± 0.4, before gradually regressing after Day 15. Serum progesterone concentration increased from Day 1 after ovulation, peaking at 27.0 ± 9.6 ng/mL between 7 and 10 days after ovulation. Progesterone concentration dropped precipitously around Day 15 after ovulation and was below 2 ng/mL around Day 17 ± 2. A day effect (p < 0.0001) was observed for corpus luteum's volume, progesterone concentration, and uterine tone, but not for endometrial edema (p > 0.05). This study helps to clarify and define normal estrous characteristics of jennies in the Eastern Caribbean.

11.
Reprod Biol Endocrinol ; 9: 63, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21569635

RESUMO

BACKGROUND: PreImplantation Factor (PIF), a novel peptide secreted by viable embryos is essential for pregnancy: PIF modulates local immunity, promotes decidual pro-adhesion molecules and enhances trophoblast invasion. To determine the role of PIF in post-fertilization embryo development, we measured the peptide's concentration in the culture medium and tested endogenous PIF's potential trophic effects and direct interaction with the embryo. METHODS: Determine PIF levels in culture medium of multiple mouse and single bovine embryos cultured up to the blastocyst stage using PIF-ELISA. Examine the inhibitory effects of anti-PIF-monoclonal antibody (mAb) added to medium on cultured mouse embryos development. Test FITC-PIF uptake by cultured bovine blastocysts using fluorescent microscopy. RESULTS: PIF levels in mouse embryo culture medium significantly increased from the morula to the blastocyst stage (ANOVA, P = 0.01). In contrast, atretic embryos medium was similar to the medium only control. Detectable - though low - PIF levels were secreted already by 2-cell stage mouse embryos. In single bovine IVF-derived embryos, PIF levels in medium at day 3 of culture were higher than non-cleaving embryos (control) (P = 0.01) and at day 7 were higher than day 3 (P = 0.03). In non-cleaving embryos culture medium was similar to medium alone (control). Anti-PIF-mAb added to mouse embryo cultures lowered blastocyst formation rate 3-fold in a dose-dependent manner (2-way contingency table, multiple groups, X2; P = 0.01) as compared with non-specific mouse mAb, and medium alone, control. FITC-PIF was taken-up by cultured bovine blastocysts, but not by scrambled FITC-PIF (control). CONCLUSIONS: PIF is an early embryo viability marker that has a direct supportive role on embryo development in culture. PIF-ELISA use to assess IVF embryo quality prior to transfer is warranted. Overall, our data supports PIF's endogenous self sustaining role in embryo development and the utility of PIF- ELISA to detect viable embryos in a non-invasive manner.


Assuntos
Bovinos/embriologia , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Modelos Animais , Peptídeos/metabolismo , Animais , Bovinos/metabolismo , Células Cultivadas , Técnicas de Cultura Embrionária , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/análise , Camundongos/embriologia , Camundongos Endogâmicos C57BL , Concentração Osmolar , Peptídeos/análise , Gravidez , Fatores de Tempo
12.
Reprod Fertil Dev ; 24(1): 252-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22394966

RESUMO

Endometritis is common in post partum dairy cows and is associated with impaired reproductive performance reflected in reduced first service conception, reduced hazard of pregnancy over the breeding period and increased risk of reproductive culling. The observed effects may be mediated directly by bacterial products, such as lipopolysaccharide (LPS, endotoxin), or indirectly by inflammatory mediators, such as cytokines, eicosanoids, nitric oxide and oxidative stress affecting sperm, ovarian, uterine and embryonic function. An inflammatory milieu in the uterus has been associated with changes in sperm motility and function as well as increased sperm phagocytosis. Zygotes resulting from fertilisation of oocytes with sperm subjected to oxidative stress are less likely to develop to the blastocyst stage. In addition, LPS and tumour necrosis factor-α (TNFα) impair follicular steroidogenesis, growth and ovulation. Oocytes exposed to LPS or prostaglandin (PG) F(2α) during maturation are less likely to develop to blastocyst stage after fertilisation. Embryos exposed to inflammatory mediators during development have fewer trophoectoderm cells. Nitric oxide impairs development of preimplantation embryos and TNFα increases blastomere apoptosis. Endometritis in women has been associated with higher rates of implantation failure. Extragenital inflammation (e.g. mastitis) is also associated with an increased rate of embryonic loss in cattle. These observations make it clear that direct and indirect effects of endometritis, and inflammation in general, can interrupt successful reproduction at several crucial stages.


Assuntos
Bovinos/fisiologia , Endometrite/fisiopatologia , Prenhez/fisiologia , Animais , Desenvolvimento Embrionário/fisiologia , Feminino , Fertilização/fisiologia , Ovulação/fisiologia , Gravidez
13.
Reprod Biol Endocrinol ; 7: 55, 2009 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-19476661

RESUMO

BACKGROUND: Contamination of the uterine lumen with bacteria is ubiquitous in cattle after parturition. Some animals develop endometritis and have reduced fertility but others have no uterine disease and readily conceive. The present study tested the hypothesis that postpartum cattle that develop persistent endometritis and infertility are unable to limit the inflammatory response to uterine bacterial infection. METHODS: Endometrial biopsies were collected several times during the postpartum period from animals that were subsequently infertile with persistent endometritis (n = 4) or had no clinical disease and conceived to first insemination (n = 4). Quantitative PCR was used to determine the expression of candidate genes in the endometrial biopsies, including the Toll-like receptor (TLR 1 to 10) family of innate immune receptors, inflammatory mediators and their cognate receptors. Selected proteins were examined by immunohistochemistry. RESULTS: The expression of genes encoding pro-inflammatory mediators such as interleukins (IL1A, IL1B and IL6), and nitric oxide synthase 2 (NOS2) were higher during the first week post partum than subsequently. During the first week post partum, there was higher gene expression in infertile than fertile animals of TLR4, the receptor for bacterial lipopolysaccharide, and the pro-inflammatory cytokines IL1A and IL1B, and their receptor IL1R2. The expression of genes encoding other Toll-like receptors, transforming growth factor beta receptor 1 (TGFBR1) or prostaglandin E2 receptors (PTGER2 and PTGER4) did not differ significantly between the animal groups. Gene expression did not differ significantly between infertile and fertile animals after the first week postpartum. However, there were higher ratios of IL1A or IL1B mRNA to the anti-inflammatory cytokine IL10, during the first week post partum in the infertile than fertile animals, and the protein products of these genes were mainly localised to the epithelium of the endometrium. CONCLUSION: Cattle may maintain fertility by limiting the inflammatory response to postpartum bacterial infection in the endometrium during the first week after parturition.


Assuntos
Doenças dos Bovinos/genética , Doenças dos Bovinos/imunologia , Endométrio/imunologia , Fertilidade/imunologia , Período Pós-Parto/imunologia , Doenças Uterinas , Animais , Biópsia , Bovinos , Doenças dos Bovinos/patologia , Citocinas/genética , Endométrio/patologia , Feminino , Fertilidade/genética , Expressão Gênica/imunologia , Infecções/imunologia , Infecções/patologia , Infecções/veterinária , Infertilidade Feminina/genética , Infertilidade Feminina/imunologia , Infertilidade Feminina/patologia , Antígenos Comuns de Leucócito/genética , Receptores de Lipopolissacarídeos/genética , Antígeno 96 de Linfócito/genética , Proteína Adaptadora de Sinalização NOD1/genética , Proteínas Serina-Treonina Quinases/genética , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Prostaglandina/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores Toll-Like/genética , Doenças Uterinas/genética , Doenças Uterinas/imunologia , Doenças Uterinas/veterinária
14.
J Vet Med Educ ; 36(1): 16-21, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19435986

RESUMO

Food supply veterinarians who intend to enter dairy cattle practice or other related career activities are in need of up-graded skills to better serve the dairy industry as it continues to evolve. The time available for students to increase their abilities within the conventional professional curriculum is scarce, especially as those with food-supply interests are a minority of students competing for time and resources. The dairy industry has need of skilled veterinarians who are not only well versed in their traditional capabilities, but who also have an understanding of the complete picture of that industry as a "farm-to-fork" experience. Society at large also stands to benefit from the presence of skilled dairy veterinarians contributing to the production of safe, affordable dairy foodstuffs in a manner deemed sustainable and humane. Veterinarians in practice can and do acquire the necessary skills to make themselves relevant to their clients and consumers; however, better preparation of entry-level veterinarians could increase their value to their employers, clients, themselves, and society in a more timely manner. Cornell University's College of Veterinary Medicine developed the Summer Dairy Institute to provide an avenue for advancing the skills of new veterinarians as a means to address the current and future needs of the dairy industry. This article describes the need for, concept of, and experience with that program.


Assuntos
Competência Clínica , Indústria de Laticínios/educação , Educação em Veterinária , Internato não Médico , Médicos Veterinários/psicologia , Medicina Veterinária , Animais , Bovinos , Currículo , Feminino , Inspeção de Alimentos , Abastecimento de Alimentos/normas , Humanos , Estudantes/psicologia , Ensino/métodos , Ensino/normas , Recursos Humanos
15.
Am J Vet Res ; 80(3): 306-310, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30801209

RESUMO

OBJECTIVE To evaluate use of flunixin meglumine as a treatment to postpone ovulation in mares, mare fertility after flunixin meglumine treatment during estrous cycles, and effects of flunixin meglumine on function of the corpus luteum after ovulation. ANIMALS 13 healthy mares. PROCEDURES A single-blinded, placebo-controlled, crossover study was conducted. Flunixin meglumine (1.1 mg/kg, IV, q 24 h) or lactated Ringer solution (placebo treatment) was administered for 2 days to mares with a dominant follicle (≥ 35 mm in diameter) and behavioral signs of estrus. Mares then were bred by artificial insemination. Number of days to ovulation from initial detection of a follicle ≥ 30 mm in diameter, uterine edema score, and pregnancy were determined by ultrasonography; the examiner was unaware of the treatment of each mare. Serum progesterone concentrations were evaluated 5 and 12 days after ovulation by use of radioimmunoassay. RESULTS Data were available for 45 estrus cycles of the 13 mares. Number of days to ovulation from initial detection of a follicle ≥ 30 mm was not significantly affected by administration of flunixin meglumine versus the placebo. Per-cycle pregnancy rate was not significantly different between flunixin meglumine (20/24 [83%] breedings) and the placebo (13/19 [68%] breedings). Flunixin meglumine did not significantly affect behavioral signs of estrus, uterine edema, or serum progesterone concentrations. CONCLUSIONS AND CLINICAL RELEVANCE Findings did not support the use of flunixin meglumine to postpone ovulation in mares.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Clonixina/análogos & derivados , Cavalos , Ovulação/efeitos dos fármacos , Animais , Clonixina/farmacologia , Corpo Lúteo/efeitos dos fármacos , Estudos Cross-Over , Ciclo Estral/efeitos dos fármacos , Estro/efeitos dos fármacos , Feminino , Inseminação Artificial/veterinária , Gravidez , Progesterona , Método Simples-Cego
16.
Anim Reprod Sci ; 202: 87-95, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30772105

RESUMO

Augmentation of parturition can be used to advance labor in mares to occur at a time when personnel is available to assist if necessary. We performed a retrospective study to determine the efficacy and safety of augmentation to manage foalings. Augmentation was performed with 3 IU oxytocin i.v. when mammary calcium concentrations were ≥250 ppm, mammary secretion pH ≤ 6.5, and the mare showed impending signs of parturition. Augmented parturitions (n = 19) were compared with three different control groups. The three control groups were: 1) Time Match control (n = 37) which were non-augmented foalings in the barn during the same time period; 2) Mare Match control (n = 32) which were the non-augmented parturitions of the augmented mares in previous years; and 3) Historic Match control (n = 165) consisted of foalings that occurred from 2006 to 2016 in the facility. All augmented mares foaled within two h with an average of 44 min (range 20-75) after oxytocin injection. The interval between foaling and the foal standing was shorter in augmented parturitions compared with historic match controls. The interval between foaling and the foal nursing was longer with augmented parturitions compared with time match and historic match controls. Duration of fetal membrane retention was not different between all groups. Augmentation of imminent parturition is potentially a safe and effective treatment for mares and foals. Implementation of augmentation as a routine procedure may increase the likelihood of enteral administration of colostrum to foals.


Assuntos
Cálcio/metabolismo , Glândulas Mamárias Animais/metabolismo , Ocitócicos/farmacologia , Ocitocina/farmacologia , Parto , Resultado da Gravidez/veterinária , Animais , Animais Recém-Nascidos , Cruzamento , Feminino , Cavalos , Concentração de Íons de Hidrogênio , Gravidez , Estudos Retrospectivos , Fatores de Tempo
17.
Arch Biochem Biophys ; 477(2): 239-43, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18554499

RESUMO

Tritrichomonas foetus is a serious veterinary pathogen, causing bovine trichomoniasis and affecting cattle herds world-wide, resulting in inflammation of the genital tract, infertility and huge economic losses. The parasite secretes a cysteine protease (CP8), which induces cytotoxicity and apoptosis in bovine vaginal and uterine epithelial cells. Mallinson et al. [D.J. Mallinson, J. Livingstone, K.M. Appleton, S.J. Lees, G.H. Coombs, M.J. North, Microbiology 1995, 141 (12) 3077-3085.] originally reported a partial DNA sequence of T. foetus CP8 based on PCR cloning of T. foetus genomic DNA. Here we report the biochemical properties of the CP8 enzyme. Kinetic properties and the substrate specificity profile of T. foetus CP8 were studied using positional scanning synthetic combinatorial libraries and Michaelis-Menten kinetic analysis of three synthetic fluorogenic substrates. The preferred substrate Z-Leu-Arg-MCA prevented host-cell death/apoptosis induced by CP8. In addition, the DNA sequence was completed by 3' and 5' rapid amplification of cDNA ends (RACE) and the full-length amino acid sequence was obtained.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Cisteína Endopeptidases/administração & dosagem , Cisteína Endopeptidases/química , Tritrichomonas foetus/enzimologia , Animais , Cisteína Endopeptidases/genética , Ativação Enzimática , Estabilidade Enzimática , Cinética
20.
PLoS One ; 12(5): e0177356, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542500

RESUMO

The objective of this study was to determine the effects of uterine and systemic inflammatory responses to uterine bacterial contamination at calving in dairy cows on the growth and ovulatory outcomes of the first dominant follicle postpartum. Ovulatory capability of the first dominant follicle postpartum was predicted in 53 multiparous cows by using a combination of follicle growth characteristics and circulating estradiol concentrations. Endotoxin levels were assayed in follicular fluid samples that were aspirated the day after ovulatory outcome prediction. Plasma levels of haptoglobin, a proinflammatory acute phase protein, and paraoxonase, a negative acute phase protein were determined. Uterine bacteria and inflammation were evaluated in three uterine fluid samples from each cow collected on the day of calving, the day after follicle aspiration, and at 35 days postpartum. Cows that had a strong initial uterine inflammatory response (robust recruitment of polymorphonuclear leukocytes of ≥ 35% and cows with uterine pH < 8.5 on the day of calving) were more likely to have an ovulatory first dominant follicle. Follicular fluid endotoxin levels were higher in non-ovulatory cows compared with ovulatory cows. Endotoxin levels in circulation were not different between ovulatory groups but were higher prepartum than on day 7 and 14 postpartum. Systemic inflammation characterized by elevated haptoglobin concentrations was higher in non-ovulatory cows despite similar bacterial contamination and circulating endotoxin levels. Paraoxonase activity in follicular fluid was significantly associated with the paraoxonase activity in plasma, however, plasma paraoxonase concentrations were not different between non-ovulatory and ovulatory cows. Cows with a higher uterine bacterial load on the day of calving had slower ovarian follicle growth. In summary, a robust uterine inflammatory response on the day of calving was positively associated with ovarian function while elevated systemic inflammation during the early postpartum period was negatively associated with the ovulatory status of the first dominant follicle postpartum.


Assuntos
Indústria de Laticínios , Folículo Ovariano/fisiopatologia , Período Pós-Parto/fisiologia , Doenças Uterinas/veterinária , Animais , Bovinos , Feminino , Inflamação/fisiopatologia , Inflamação/veterinária , Ovulação , Doenças Uterinas/fisiopatologia
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