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We report the case of a bilateral and multilocular spermatocele and sperm granuloma in a dog that was vasectomized 5 years before. Clinical examination revealed scrotal dermatitis and benign prostatic hyperplasia. Orchiectomy was performed, and gross and histological examination showed testicular degeneration associated with epididymal sperm granuloma. In relation to this case, the literature about long-term effects of vasectomy in dogs has been reviewed. On the basis of these results, a preventive sonogram and physical assessment in prostate and other reproductive structures before vasectomy is recommended.  相似文献   
83.
With the commercial release in Australia in 2004 of a vaccine against feline immunodeficiency virus (FIV; Fel‐O‐Vax FIV®), the landscape for FIV diagnostics shifted substantially. Point‐of‐care (PoC) antibody detection kits, which had been the mainstay for diagnosing FIV infection since the early 1990s, were no longer considered accurate to use in FIV‐vaccinated cats, because of the production of vaccine‐induced antibodies that were considered indistinguishable from those produced in natural FIV infections. Consequently, attention shifted to alternative diagnostic methods such as nucleic acid detection. However, over the past 5 years we have published a series of studies emphasising that FIV PoC test kits vary in their methodology, resulting in differing accuracy in FIV‐vaccinated cats. Importantly, we demonstrated that two commercially available FIV antibody test kits (Witness? and Anigen Rapid?) were able to accurately distinguish between FIV‐vaccinated and FIV‐infected cats, concluding that testing with either kit offers an alternative to PCR testing. This review summarises pertinent findings from our work published in a variety of peer‐reviewed research journals to inform veterinarians (particularly veterinarians in Australia, New Zealand and Japan, where the FIV vaccine is currently commercially available) about how the approach to the diagnosis of FIV infection has shifted. Included in this review is our work investigating the performance of three commercially available FIV PoC test kits in FIV‐vaccinated cats and our recommendations for the diagnosis of FIV infection; the effect of primary FIV vaccination (three FIV vaccines, 4 weeks apart) on PoC test kit performance; our recommendations regarding annual testing of FIV‐vaccinated cats to detect ‘vaccine breakthroughs’; and the potential off‐label use of saliva for the diagnosis of FIV infection using some FIV PoC test kits. We also investigated the accuracy of the same three brands of test kits for feline leukaemia virus (FeLV) diagnosis, using both blood and saliva as diagnostic specimens. Based on these results, we discuss our recommendations for confirmatory testing when veterinarians are presented with a positive FeLV PoC test kit result. Finally, we conclude with our results from the largest and most recent FIV and FeLV seroprevalence study conducted in Australia to date.  相似文献   
84.
The objective of this study was to investigate differences on the endometrial immunoexpression of type I IFN receptor subunit 1 (IFNAR1) and oxytocin receptor (OTR) during the time of maternal recognition of pregnancy in sheep, when oestrus is synchronized with either prostaglandin analogues (group PG) or conventional progestagens (group P). Plasma progesterone was measured from day 0 to 21 post‐coitus (pc) (day 0 = day of oestrus). Immunohistochemistry was performed in samples of uterine horns from pregnant sheep on days 9pc, 13pc, 15pc, 17pc and 21pc to locate IFNAR1 and OTR expression in different endometrial compartments. Mean levels of plasma progesterone were different between treatments, obtaining higher levels in the PG group than in the P group (p < 0.05). Comparing days of pregnancy, IFNAR1 protein expression was different in the luminal epithelium (LE) (p < 0.05), while OTR was different in the LE and in the superficial glandular epithelium (SG) (p < 0.05). Temporal variation on the expression of both proteins from day 9pc to 21pc has been evidenced. IFNAR1 and OTR expression did not show significant differences between treatments. However, the response observed in the endometrium was highly inconsistent when prostaglandin analogues were used. Therefore, the protocol based on prostaglandin analogues still needs to be optimized before being considered as a better alternative to progestagens for oestrous synchronization in sheep.  相似文献   
85.
This study was conducted to characterize the daily profile of testosterone secretion and its mean concentrations in the four seasons as well as to evaluate the semen characteristics and testicular biometry of Mangalarga Marchador stallions throughout the year in a tropical region. Three stallions were submitted to semen collections and evaluation of testicular biometry every 14 days along a year. Blood samples were collected once at the middle of each season, in a 20‐min interval during 24 hr in order to evaluate the testosterone secretion profiles among seasons. Testosterone concentrations along the day were higher at the beginning of the afternoon (from 12:00 to 15:00 hr), but a circadian secretion was not clearly observed. Mean testosterone concentrations did not differ among seasons (p > .05), but a pattern of secretion along the day showed variations with higher concentrations in the afternoon during the winter. Ejaculate volume was higher during summer; however, sperm motility decreased in summer and spring. Total sperm in ejaculate, sperm morphology and testicular biometry kept constant along the year showing no differences among the seasons. The results demonstrated that in a tropical region, reproductive aspects of stallions did not show a clearly defined seasonal variation, and months of autumn and winter were not unsuitable for reproduction of the males.  相似文献   
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SUMMARY The effects of induced parturition on calf mortality rates were studied in 24 winter-calving, pasture-fed, dairy herds in south-western Victoria. Parturition was induced when most cows were between 27 and 35 weeks of pregnancy. Control groups were selected from cows in the same herds in which calving was not induced. The incidence of mortality within 7 days of birth was much higher among calves from cows in induced groups relative to those in control groups (estimated median herd mortality incidence 72% and 7%, respectively). The incidence of calf mortality was high among groups induced at all stages of pregnancy that were investigated. However, differences in calf mortality incidence, relative to controls, were increased among groups induced at earlier stages of pregnancy.  相似文献   
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