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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.

3.
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.

4.
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.

5.
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.

6.
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
7.
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
8.
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
9.
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
11.
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
12.
Oncotarget ; 8(20): 32419-32432, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28423690

RESUMO

Recurrent pregnancy loss (RPL) affects 2-3% of couples. Despite a detailed work-up, the etiology is frequently undefined, leading to non-targeted therapy. Viable embryos and placentae express PreImplantation Factor (PIF). Maternal circulating PIF regulates systemic immunity and reduces circulating natural killer cells cytotoxicity in RPL patients. PIF promotes singly cultured embryos' development while anti-PIF antibody abrogates it. RPL serum induced embryo toxicity is negated by PIF. We report that PIF rescues delayed embryo development caused by <3 kDa RPL serum fraction likely by reducing reactive oxygen species (ROS). We reveal that protein disulfide isomerase/thioredoxin (PDI/TRX) is a prime PIF target in the embryo, rendering it an important ROS scavenger. The 16F16-PDI/TRX inhibitor drastically reduced blastocyst development while exogenous PIF increased >2 fold the number of embryos reaching the blastocyst stage. Mechanistically, PDI-inhibitor preferentially binds covalently to oxidized PDI over its reduced form where PIF avidly binds. PIF by targeting PDI/TRX at a distinct site limits the inhibitor's pro-oxidative effects. The >3kDa RPL serum increased embryo demise by three-fold, an effect negated by PIF. However, embryo toxicity was not associated with the presence of putative anti-PIF antibodies. Collectively, PIF protects cultured embryos both against ROS, and higher molecular weight toxins. Using PIF for optimizing in vitro fertilization embryos development and reducing RPL is warranted.


Assuntos
Aborto Habitual/terapia , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/farmacologia , Aborto Habitual/metabolismo , Aborto Habitual/prevenção & controle , Animais , Bovinos , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Humanos , Camundongos , Peptídeos/metabolismo , Gravidez , Proteínas da Gravidez/metabolismo
13.
J Vet Diagn Invest ; 29(5): 696-699, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28423988

RESUMO

An aged mixed-breed goat doe was presented with a 9-mo history of serosanguineous vaginal discharge. Vaginal speculum examination revealed serosanguineous discharge but otherwise no abnormalities. Transrectal ultrasonography showed normal ovaries and multifocal cystic lesions within the uterus. Ovariohysterectomy was recommended because of a strong suspicion of neoplasia. Multiple, non-resectable masses were noted in and around the uterus intraoperatively, and euthanasia was elected. Autopsy revealed multiple masses within the uterus, cervix, and lung parenchyma. Histologically, the masses within the uterus represented a likely collision tumor of primary adenocarcinoma and leiomyosarcoma. Our report highlights the importance of obtaining biopsy samples of all masses because the lesions described showed significantly different biological behavior. This information is vital to guide treatment and prognosis.


Assuntos
Adenocarcinoma/veterinária , Doenças das Cabras/diagnóstico , Leiomiossarcoma/veterinária , Neoplasias Uterinas/veterinária , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Animais , Feminino , Doenças das Cabras/diagnóstico por imagem , Doenças das Cabras/patologia , Cabras , Leiomiossarcoma/diagnóstico , Leiomiossarcoma/patologia , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/patologia
14.
Vet Clin North Am Food Anim Pract ; 32(2): 387-410, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27324451

RESUMO

Postpartum diseases are common in dairy cows, and their incidence contributes to reduced fertility and increased risk of culling, making their prevention and management extremely important. Reproductive efficiency has a major impact on economic success of any dairy production unit. Optimizing reproductive efficiency contributes to overall efficiency of production units, minimizing environmental impacts and contributing to sustainability of food production. Additionally, control of reproductive diseases is important for maintenance of health and welfare of dairy cows; for minimizing use of antibiotics; and ensuring a wholesome, safe, and nutritious product.


Assuntos
Criação de Animais Domésticos , Doenças dos Bovinos/prevenção & controle , Indústria de Laticínios , Endometrite/veterinária , Transtornos Puerperais/veterinária , Animais , Bovinos , Endometrite/prevenção & controle , Feminino , Transtornos Puerperais/prevenção & controle , Reprodução
15.
Theriogenology ; 85(8): 1367-74, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26944540

RESUMO

Endometrial samples were obtained from 56 consecutively calving dairy cows examined for endometrial cytology and for aerobic and anaerobic bacterial growth. Changes over time, correlations between different cell types and between cell and bacterial populations and with fertility measures were calculated. The proportion of neutrophils in cytologic preparations decreased with time postpartum. Other cell types did not change significantly with time. The proportion of neutrophils early (Day 0 and 7) postpartum was negatively correlated with neutrophil proportion at 5 or 7 weeks postpartum and positively correlated with fertility. Cows with high proportion of neutrophils at 7 days postpartum (>40%) were significantly more likely to become pregnant than those with lower proportions of neutrophils. Escherichia coli were the bacteria most frequently isolated at 0 or 7 days postpartum but were uncommon after that. Trueperella pyogenes were most prevalent at 3 weeks postpartum and were more likely to infect cows that had previously been infected with E coli. The presence of T pyogenes at 3 weeks postpartum increased the risk of concomitant or later infection with gram-negative anaerobes. The presence of T pyogenes at 3 weeks postpartum significantly reduced the risk of pregnancy at 150 days in milk. The presence of alpha-hemolytic Streptoccus spp. at 7 days postpartum was associated with improved reproductive performance. The proportion of neutrophils at 5 and 7 weeks postpartum was related to concomitant bacterial infection. These findings suggest that rapid mobilization of neutrophils to the postpartum uterus is a beneficial response for uterine health in dairy cows.


Assuntos
Endometrite/veterinária , Endométrio/patologia , Fertilidade , Período Pós-Parto , Actinomycetales/classificação , Actinomycetales/isolamento & purificação , Infecções por Actinomycetales/complicações , Infecções por Actinomycetales/epidemiologia , Infecções por Actinomycetales/veterinária , Animais , Contagem de Células Sanguíneas , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Endometrite/complicações , Endometrite/microbiologia , Endométrio/microbiologia , Escherichia coli/classificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/veterinária , Feminino , Neutrófilos/citologia
16.
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
17.
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
18.
PLoS One ; 9(7): e100263, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24983882

RESUMO

BACKGROUND: Endogenous PIF, upon which embryo development is dependent, is secreted only by viable mammalian embryos, and absent in non-viable ones. Synthetic PIF (sPIF) administration promotes singly cultured embryos development and protects against their demise caused by embryo-toxic serum. To identify and characterize critical sPIF-embryo protein interactions novel biochemical and bio-analytical methods were specifically devised. METHODS: FITC-PIF uptake/binding by cultured murine and equine embryos was examined and compared with scrambled FITC-PIF (control). Murine embryo (d10) lysates were fractionated by reversed-phase HPLC, fractions printed onto microarray slides and probed with Biotin-PIF, IDE and Kv1.3 antibodies, using fluorescence detection. sPIF-based affinity column was developed to extract and identify PIF-protein interactions from lysates using peptide mass spectrometry (LC/MS/MS). In silico evaluation examined binding of PIF to critical targets, using mutation analysis. RESULTS: PIF directly targets viable cultured embryos as compared with control peptide, which failed to bind. Multistep Biotin-PIF targets were confirmed by single-step PIF-affinity column based isolation. PIF binds protein disulfide isomerases a prolyl-4-hydroxylase ß-subunit, (PDI, PDIA4, PDIA6-like) containing the antioxidant thioredoxin domain. PIF also binds protective heat shock proteins (70&90), co-chaperone, BAG-3. Remarkably, PIF targets a common RIKP [corrected] site in PDI and HSP proteins. Further, single PIF amino acid mutation significantly reduced peptide-protein target bonding. PIF binds promiscuous tubulins, neuron backbones and ACTA-1,2 visceral proteins. Significant anti-IDE, while limited anti-Kv1.3b antibody-binding to Biotin-PIF positive lysates HPLC fractions were documented. CONCLUSION: Collectively, data identifies PIF shared targets on PDI and HSP in the embryo. Such are known to play a critical role in protecting against oxidative stress and protein misfolding. PIF-affinity-column is a novel utilitarian method for small molecule targets direct identification. Data reveals and completes the understanding of mechanisms involved in PIF-induced autotrophic and protective effects on the embryo.


Assuntos
Embrião de Mamíferos/metabolismo , Peptídeos/fisiologia , Dobramento de Proteína , Sequência de Aminoácidos , Animais , Sítios de Ligação , Simulação por Computador , Desenvolvimento Embrionário , Cavalos/embriologia , Camundongos , Modelos Moleculares , Estresse Oxidativo , Peptídeos/química , Peptídeos/metabolismo , Estrutura Terciária de Proteína , Tiorredoxinas/metabolismo
19.
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
20.
Vet J ; 197(2): 324-8, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23384437

RESUMO

The major objective of this study was to determine whether short-term preovulatory progestagen treatment of mares could effectively delay ovulation. Secondary objectives were to determine the effect such supplementation had on signs of estrus, follicular growth, postovulatory luteal function and pregnancy rate. Thirteen cyclic mares of different breeds were used in this study during the natural breeding season. Once mares were confirmed in estrus with a follicle of 35 mm in diameter, they were assigned in random order to receive no treatment (control), placement of a progesterone-impregnated controlled intravaginal drug releasing device (CIDR) for 2 days, or oral altrenogest treatment (0.044 mg/kg/d) for 2 days. Transrectal ultrasonography and teasing with a vigorous stallion were performed daily. Mares were inseminated every 48 h after the end of experimental treatment (progestagen groups) or beginning when the follicular diameter was 35 mm (control group) with fresh extended semen of a single fertile stallion. Each mare was followed for 3-5 cycles, allowing each treatment to be applied one or two times. Neither CIDR nor altrenogest treatment delayed ovulation. Treatment had no effect on follicular growth rate or the size of the ovulatory follicle immediately preceding ovulation. Both forms of progestagen treatment effectively abolished estrous behavior within 24h. Estrous response to the stallion returned to the control level after cessation of treatment. Similarly, a reduction in endometrial edema was detected during progestagen treatment, which returned to normal after cessation of treatment. Altrenogest treatment tended to reduce the chance of pregnancy (P=0.09) compared to the control group. The use of progestagens to delay ovulation in mares lacks efficacy and may threaten successful establishment of pregnancy.


Assuntos
Cavalos/fisiologia , Ovulação/efeitos dos fármacos , Progesterona/farmacologia , Progestinas/farmacologia , Acetato de Trembolona/análogos & derivados , Animais , Preparações de Ação Retardada , Esquema de Medicação , Sincronização do Estro , Feminino , Ovulação/fisiologia , Gravidez , Progesterona/administração & dosagem , Progestinas/administração & dosagem , Acetato de Trembolona/administração & dosagem , Acetato de Trembolona/farmacologia
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