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11.
OBJECTIVE: To evaluate the cytopathic effects of Tritrichomonas foetus and a purified cysteine protease (ie, CP30) of T foetus on cultured bovine uterine epithelial cells (BUECs) in vitro. SAMPLE POPULATION: 10 reproductive tracts were obtained from late-term bovine fetuses at a commercial abattoir. PROCEDURE: An in vitro culture system of BUECs was developed to study the cytopathic effects of T foetus and purified CP30 of T foetus on host cells. Cytotoxicity of T foetus or CP30 on exposed BUECs was determined. Fluorescence microscopy and flow cytometry analyses were used to detect apoptosis. A fluorometric assay was used to detect BUEC caspase 3 activation. The CP inhibitor E-64 and a caspase inhibitor were used to inhibit apoptosis. RESULTS: Cytopathic effects were observed in BUECs treated with parasites or CP30 and were concentration and time dependent. The BUECs underwent apoptosis in the presence of parasites or CP30. The specific CP inhibitor E-64 abolished the induction of apoptosis in BUECs by CP30. The caspase inhibitor reduced the amount of apoptosis in BUECs. CONCLUSIONS AND CLINICAL RELEVANCE: T foetus and its CP30 induce apoptosis in cultured BUECs in vitro. Induction of apoptosis by CP30 is correlated with protease activity. Endometrial cell death as a result of a T foetus infection is likely to be more important in mediating infertility than a direct effect on the conceptus. Provoking an apoptotic reaction in the host may mitigate an inflammatory reaction or immune response and therefore favor survival of the parasite in a chronic infection.  相似文献   
12.
集约化商品肉鸡生产企业的目标是每只入舍母鸡能够生产出最大数量的可孵化种蛋和最多的高质量雏鸡。在适当的饲养管理条件下,一只母鸡产蛋可超过180个,鸡肉产量达到270kg。这些生产数据在鸡只之间存在着非常大的差距,其原因可追溯至种蛋的收集标准、储存条件和孵化条件。在坚持种蛋选择与分级的基础上进行常规性的饲养管理,生产企业获得最大收益的目标不难实现。  相似文献   
13.
The indirect fluorescent antibody (IFA) test for Theileria equi was evaluated to assess test's suitability for the serological diagnosis of equine piroplasmosis, to provide performance parameters for the purpose of test validation, and to compare it with the complement fixation (CF) test. Using a protocol that included Evan's blue, the specificity of the IFA test was estimated at 99.0% for T. equi by the classical method of analysis, and 96.6% by the Bayesian method. The use of Evan's blue in the test protocol increased test specificity and contributed to an excellent test agreement between two collaborating laboratories (kappa = 0.96). Using Bayesian analysis, the sensitivity estimate for the IFA test was 89.2%. The CF test sensitivity and specificity estimates for T. equi were 63.1 and 96.4%, respectively, as determined by Bayesian analysis. The IFA test was more sensitive than the CF test but the specificity estimates were similar.  相似文献   
14.
A fecal sample from a 42-year-old goat with a 2-month history of poor weight gain and diarrhea yielded a moderate growth of an organism resembling Salmonella spp. on MacConkey agar. The organism was identified as Escherichia fergusonii. The animal was euthanized. Samples of intestine, lung, liver, and kidney yielded the same organism, E. fergusonii.  相似文献   
15.
OBJECTIVE: To radiographically evaluate the Zurich cementless total hip (ZCTH) cup and correlate lucency with clinical signs of implant instability, time since surgery, and implant generation, using zonal analysis. STUDY DESIGN: Retrospective study. ANIMALS: Client-owned dogs (n = 53). METHODS: Radiographs of dogs that had ZCTH arthroplasty (>1 year) were evaluated using zonal analysis, for lucency surrounding the cup-bone interface (number of zones, length, area). Dogs were examined for clinical signs of implant instability (lameness, hip pain). Lucency was correlated with lameness, time after surgery, and implant generation. RESULTS: Radiographs of 68 implants (18 generation I, 50 generation II) were evaluated. Eight dogs were lame (11.8%). Dogs with lameness were more likely to have lucency in > or =2 zones of analysis (per view), have >2 times the average curvilinear length of lucency, and have >4 times the average area of lucency surrounding the implant compared with non-lame dogs. A weak relationship was observed between time after surgery and implant generation; however, there was no relationship between time after surgery and lucency. CONCLUSIONS: Dogs with lameness after ZCTH arthroplasty were more likely to have lucency at the cup-bone interface. Lucency was better evaluated by radiographic projection than zonal analysis. Temporal progression of lucency was weakly correlated with implant generation. CLINICAL RELEVANCE: Dogs with lucency in > or =2 zones of analysis should be evaluated more frequently for clinical signs of implant loosening. Further investigation of serial radiographs after ZCTH arthroplasty is warranted.  相似文献   
16.
17.
OBJECTIVE: To determine whether plasma, urine, and fecal electrolyte and mineral concentrations differ between clinically normal horses and Thoroughbreds with recurrent exertional rhabdomyolysis (RER) after consumption of diets varying in cation-anion balance. ANIMALS: 5 Thoroughbred mares with RER and 6 clinically normal mixed-breed mares. PROCEDURE: Each of 3 isocaloric diets designated as low, medium, and high on the basis of dietary cation-anion balance (DCAB) values of 85, 190, and 380, respectively, were fed to horses for 14 days. During the last 72 hours, 3 horses with RER and 3 control horses had daily urine and fecal samples obtained by total 24-hour collection. Remaining horses had urine samples collected daily by single catheterization. RESULTS: For each diet, no differences existed between horses with RER and control horses in plasma pH, electrolyte concentrations, and creatine kinase activity or in urine pH and renal fractional excretion (FE) values. Plasma pH, strong ion difference, bicarbonate and total carbon dioxide concentrations, and base excess decreased and plasma chloride and ionized calcium concentrations increased with decreasing DCAB. Urine pH decreased with decreasing DCAB. The FE of chloride and phosphorus were greatest for horses fed the low diet. The FE values for all electrolytes exept magnesium did not differ between urine samples obtained by single catheterization and total 24-hour collection. Daily balance of calcium, phosphorus, sodium, chloride, and potassium did not differ significantly among horses fed the various diets. CONCLUSIONS: In clinically normal horses and in horses with RER, the DCAB strongly affects plasma and urine pH and the FE of sodium, potassium, chloride, and phosphorus.  相似文献   
18.
前言豆粕是世界各地畜禽饲养中最常用的蛋白质饲料,它有优良的氨基酸构成,可在畜禽饲养中作为玉米、高粱、大麦等谷物的补充。现已培育出了一些作物,包括大豆在内,其中整合入了一个能赋予作物以耐“草甘膦”能力的基因;草甘膦(glyphosate)是常用除草剂“农达”(Roundup~(R))中的活性成分(Padgette等,1995)。该基因编码土壤杆菌属(Agrobacterium sp.)CP4  相似文献   
19.
The lifetime probability of death from gastric dilation–volvulus (GDV) for five dog breeds was estimated based on published breed-specific longevity and GDV incidence. These breeds were Great Dane, Irish Setter, Rottweiler, Standard Poodle and Weimaraner. Lifetime risk (95% CI) of GDV in these breeds ranged from 3.9% (0–11.2%) for Rottweiler to 36.7% (25.2–44.6%) for Great Dane.

A decision-tree analysis for prophylactic gastropexy—using lifetime probability of death from GDV and expected cost savings for veterinary services as outcome measures—was undertaken to determine the preferred course of action in several dog breeds. Prophylactic gastropexy was the preferred choice of action for all breeds examined, with the reduction in mortality (versus no gastropexy) ranging from 2.2-fold (Rottweiler) to 29.6-fold (Great Dane). Assuming a prophylactic gastropexy costs US$ 400, the procedure was cost-effective when the lifetime risk of GDV was ≥34%. The maximum and minimum estimated breakeven costs for the gastopexy procedure ranged from US$ 20 (Rottweiler) to US$ 435 (Great Dane). The cost-effectiveness of prophylactic gastropexy was most sensitive to the cost of treating GDV (US$ 1500). Prophylactic gastropexy raises ethical issues that need to be considered by veterinarians and dog breeders.  相似文献   

20.
BACKGROUND: The number of pet cats is increasing in most countries, often outnumbering pet dogs, yet cats receive less veterinary care than their canine counterparts.(1) Clients state the difficulty of getting the cat into a carrier at home, driving to the clinic, and dealing with the fearful cat at the veterinary clinic as reasons for fewer visits.(2) Educating and preparing the client and the veterinary team with regard to respectful feline handling is necessary in order to avoid stress and accomplish the goal of good health care. Without such preparation, feline stress may escalate into fear or fear-associated aggression. The resulting stress may alter results of the physical examination and laboratory tests, leading to incorrect diagnoses (eg, diabetes mellitus) and unnecessary treatments.(3-5) Without compassionate and respectful handling by the veterinary team, clients may feel the team lacks skills and compassion, or does not understand cats. Injury may occur to the cat, client and/or veterinary team.(6) Clients who want to avoid stress for their cat may avoid veterinary visits or choose another practice instead. GOALS: The use of feline-friendly handling techniques should reduce these problems. Handling is most successful when the veterinary team adapts the approach to each individual cat and situation. The goal of these guidelines is to provide useful information for handling cats that can lead to: ? Reduced fear and pain for the cat. ? Reinforced veterinarian-client-cat bond, trust and confidence, and thus better lifelong medical care for the cat. ? Improved efficiency, productivity and job satisfaction for the veterinary team. ? Increased client compliance. ? Timely reporting and early detection of medical and behavioral concerns. ? Fewer injuries to clients and the veterinary team. ? Reduced anxiety for the client.  相似文献   
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