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91.
Spinal dermoid sinus in a Burmese cat with paraparesis   总被引:1,自引:1,他引:0  
A 2-year-old, male, Burmese cat was evaluated for chronic progressive hindlimb weakness, ataxia and urinary incontinence. Radiographic examination, myelography and magnetic resonance imaging defined congenital vertebral anomalies and a space-occupying intradural, extramedullary mass. A dermoid sinus was subsequently identified dorsal to the affected spine. Surgical excision of the tract necessitated a dorsal laminectomy and removal of a 1-cm diameter intradural dermoid sinus 'cyst' that contained hair and sebaceous debris. The cat recovered hindlimb function after surgery and remains asymptomatic 50 months after surgery except for a persistent inability to urinate voluntarily.  相似文献   
92.
The objective of this study was to simplify two-step addition of cryoprotectant for vitrification of bovine embryos by developing a one-step procedure. Survival was calculated as a percentage of non-vitrified controls developed from the same batch of oocytes. In experiment 1, bovine blastocysts were vitrified following one- or two-step addition of cryoprotectant. Exposure of embryos to cryoprotectant in one-step resulted in survival rates not significantly lower (p > 0.1) than those obtained by two-step addition (85% vs 98%, respectively). Based on these results, experiments 2-4 were designed to test one-step addition of cryoprotectant more rigorously. Experiment 2 exposed day 7 blastocysts to 6, 7 or 8 M ethylene glycol for 2.5 or 3.5 min. At 24 h post-vitrification, survival of embryos was similar, irrespective of ethylene glycol concentration or exposure time (6 M 38%, 7 M 51%, 8 M 59%; 2.5 min 54%, 3.5 min 45%). In experiment 3, blastocysts were exposed to 7 M ethylene glycol for shorter times (30 or 60 s); 30 s exposure resulted in decreased survival (8% vs 31%, p < 0.05). Experiment 4 concerned one-step addition of cryoprotectant to day 6 bovine morulae, exposed to 7 M ethylene glycol for 1 or 1.5 min. There was no difference in survival between exposure times of 1 or 1.5 min (28% vs 45%, respectively; p > 0.1). It is unclear why many embryos survive vitrification with one-step addition of cryoprotectant, but others do not. Although, one-step addition of cryoprotectant simplifies the vitrification procedure, survival rates were inadequate for routine cryopreservation of in vitro-produced bovine embryos.  相似文献   
93.
A study was conducted to evaluate the effects of postpartum prostaglandin treatment on reproduction in 3 seasonal calving dairy herds. Recently calved lactating dairy cows were paired on herd, age, calving date and previous production index. One cow in each of the 196 pairs received a single intramuscular injection of 25 mg of the prostaglandin analogue, dinoprost, between 14 and 28 days after calving. Subsequent reproduction was monitored. Within each herd and overall, there was no significant effect of treatment on the intervals from calving to first service, mating start date to first service, calving to conception, mating start date to conception and first service to conception. Treatment also had no significant effect on 21-day submission and pregnancy rates, on the proportion of each group not pregnant at the end of mating, and on first service pregnancy rates. Responses to treatment did not vary between cows calving within 50 days of mating start date and earlier calving cows or between cows aged less than 5 years and older cows.  相似文献   
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To meet weekly breeding targets, it is occasionally necessary to inject exogenous gonadotrophins to induce oestrus in prepubertal gilts. However, the gilt oestrus response to equine chorionic gonadotrophin (eCG) either alone or in combination with human chorionic gonadotrophin (hCG) can be unpredictable. The objective of the present study was to examine possible reasons for this unpredictability. Prepubertal gilts (90 kg and 153 days of age, n = 109) received an injection of either 600 IU eCG or a combination of 400 IU eCG and 200 IU hCG (PG600), or were non-injected controls, and were then exposed to a mature boar for 15 min daily for 7 days for oestrus detection. At the time of injection, real-time ultrasound revealed that the gilt ovaries had primarily 1–2 mm follicles. Blood samples were obtained at time of hormone injection (day 0) and at days 3, 7 and 10 for assay of serum progesterone concentrations. The oestrus responses by 7 days were15.5%, 73.3% and 0%, for eCG, PG600, and control gilts, respectively (p < 0.001). The oestrus response improved (p < 0.05) with increasing body weight. Based on circulating progesterone levels, all oestrous gilts ovulated except for four of the PG600 gilts. Failure to express oestrus in PG600 gilts was not associated with a premature rise in progesterone.  相似文献   
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ABSTRACT

This review outlines the processes followed by New Zealand Thoroughbred Racing (NZTR) when developing its Thoroughbred Welfare Assessment Guidelines. It accepted that guidance on welfare management must be based on up-to-date knowledge of how animal welfare is understood scientifically. NZTR established an expert panel to facilitate this process. First, major changes in animal welfare science thinking over the last 40 years were considered. For example, the separate biological function and affective state orientations were later accepted as dynamically interacting elements within the body operating as an integrated whole entity; conceptual problems with the Five Freedoms framework led to the formulation of the Five Provisions and Welfare Aims paradigm and development of the Five Domains Model for assessing nutritional, environmental, health, behavioural and mental facets of animal welfare; and the initial major focus on negative experiences evolved to include both negative and positive experiences. The Five Domains Model was very effective for illustrating up-to-date understanding of animal welfare and its use demonstrated how comprehensive animal welfare assessments may be conducted. The NZTR panel followed a sequential approach that included an update on animal welfare thinking and the Five Provisions and Welfare Aims paradigm; the generic Five Domains Model was refocused specifically on equids; a detailed model assessment of equine welfare practices was conducted; enhanced equine welfare practices were emphasised by comparing them to inadequate welfare practices; guidelines were framed in terms which provide domain-specific advice on provisions that achieve positive welfare; other domain-specific guidelines were focused on welfare-compromising consequences of inadequate provisions; and welfare-appropriate conditions were clarified for all stages of a Thoroughbred’s life cycle (in work and rest) to facilitate exercising a life-long duty of care. Finally, the guidelines were expressed in general terms to avoid them becoming overly detailed and unwieldy. They therefore do not address specific welfare issues such as use of whips, bits, spurs and tight nosebands, however the Five Domains Model may also be used for these specific purposes. The guidelines, and the way they were formulated, provide an example of one approach which other organisations may find immediately useful, or which may stimulate them to devise their own approaches when progressing such equine welfare initiatives.  相似文献   
99.
The distribution and prevalence of Thelleria buffeli in Queensland cattle were investigated using serum samples and blood films collected primarily for brucellosis surveillance and tick fever diagnosis. Serums from 8654 cattle from 357 farms throughout Queensland were examined by an indirect fluorescent antibody test for antibody to T buffeli. In addition, 347 peripheral blood films collected from 147 farms in south-eastern Queensland were examined for piroplasms of T buffeli. The overall herd and animal prevalences for T buffeli were 75% and 41%, respectively. There was significant variation among regions in both herd and animal prevalences (P less than 0.001). Herd and animal prevalences were highest in the north and east decreasing westward. The results indicate that T buffeli is more widespread in Queensland than previously thought.  相似文献   
100.
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