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941.
Our objective of this study was to investigate the relationship between milk urea-nitrogen concentrations ([MUN]) and first-service breeding success (FSBS) in a large number of commercial dairy herds, using various timings on [MUN]. All commercial dairy herds in Prince Edward Island on monthly milk testing (n=198) formed the sampling frame. Milk components, [MUN], 24-h milk production, and breeding data for all cows from these farms were gathered electronically from a central database. A first service between 1 June 1999 and 31 May 2000 was classified successful (FSBS=1) if it was the cow's last service and she calved 270-290 d later. Mixed logistic-regression modeling was used to determine the association between FSBS (the outcome variable) and the [MUN] closest to first service, controlling for other possible confounders and clustering effects of cows within the study herds. The final dataset included 2787 successful and 3015 unsuccessful first services. A change in [MUN] on the test closest to first service from 10 to 20 mg/dL was associated with a 13.9% reduction in the odds of FSBS (controlled for parity, milk production and days in milk).  相似文献   
942.
A clinical trial involving 122 cats with infected skin wounds or abscesses presented to 10 veterinary clinics was conducted to evaluate the efficacy of 2 oral amoxicillin drug products (a paste and a suspension). A 2nd objective of the study was to identify bacteria involved in such infections and verify their in vitro sensitivity to amoxicillin. Samples of wound exudate were harvested at the time of presentation and submitted for aerobic and anaerobic culture. The sensitivity to amoxicillin of isolates thought to be infecting agents was tested, using a standard minimum inhibitory concentration method. Pasteuralla multocida and obligate anaerobes of the genera Prevotella, Fusobacterium, and Porphyromonas were the most frequently isolated pathogens. Overall, their in vitro susceptibility to amoxicillin was very good. Both drug products were clinically efficacious with a global success rate of 95.1% for cats administered oral amoxicillin at 11-22 mg/kg bodyweight (mean 13.8 mg/kg bodyweight) twice daily for 7 to 10 days.  相似文献   
943.
Locoweed species (Astragalus and Oxytropis spp.) are a serious toxic plant problem for grazing livestock. Horses and sheep have been conditioned to avoid eating locoweed using the aversive agent LiCl. The objective of this study was to determine if previous locoweed intoxication affects food aversion learning in horses and sheep. Horses and sheep were divided into 3 treatment groups: control (not fed locoweed and not averted to a novel feed); locoweed-novel feed averted (fed locoweed and averted to a novel feed); and averted (not fed locoweed and averted to a novel feed). Animals in the locoweed-novel feed averted groups were fed locoweed during 2 periods of 21 and 14 d, respectively, with each feeding period followed by a 14-d recovery period. Animals were averted to a novel test feed at the end of the first locoweed-feeding period, and periodically evaluated for the strength and persistence of the aversion. During the first recovery period, locoweed-novel feed averted horses ate less (9.5% of amount offered) of the test feed than did control horses (99.8%) and did not generally differ from averted horses (0%). During recovery period 2, locoweed-novel feed averted horses (4.3%) differed (P = 0.001) in consumption (% of offered) of the test feed from controls (100%) and the averted group (0%). Locoweed-novel feed averted sheep differed (P = 0.001) from controls (14.4 vs. 99.5%, respectively, during recovery period 1), whereas locoweed-novel feed averted sheep did not differ (P > 0.50) from averted sheep (0.6%). During the second recovery period, control sheep (100%) differed (P < 0.05) from averted (0%) and locoweed-novel feed averted (12.2%) groups. Two intoxicated sheep (locoweed-novel feed averted) partially extinguished the aversion during the first recovery period, but an additional dose of LiCl restored the aversion. Two of 3 intoxicated horses had strong aversions that persisted without extinction; 1 horse in the locoweed-novel feed averted group had a weaker aversion. These findings suggest that horses and sheep previously intoxicated by locoweeds can form strong and persistent aversions to a novel feed, but in some animals, those aversions may not be as strong as in animals that were never intoxicated.  相似文献   
944.
945.
Veterinary Research Communications - Galuppi, R., Avenoso, A.M., Leotti, G., Ostanello, F., Poglayen, G. and Tampieri, M.P., 2007. Diagnosis of sarcoptic mange in slaughtered swine. Veterinary...  相似文献   
946.
A 9-year-old male cat was presented for evaluation of chronic weight loss and was subsequently diagnosed with pericardial effusion. The effusion was quantified as a septic exudate caused by the anaerobic bacterium Peptostreptococcus. Antibiotic therapy resulted in complete resolution of the pericardial effusion. As Peptostreptococcus is a common oral bacterium and the cat had a previous dental procedure, it is speculated that the pericardial effusion was secondary to bacteraemia from the dental procedure.  相似文献   
947.
OBJECTIVE: To compare procedure time, complications, mortality, and short-term outcome in dogs with patent ductus arteriosus (PDA) treated by surgical ligation (SL) or transarterial coil occlusion (TCO). STUDY DESIGN: Retrospective study. ANIMALS: Dogs with PDA (n=204). METHODS: Medical records of dogs treated for PDA were reviewed. Dogs treated by SL when it was the primary method used for PDA treatment (1993-1998) were compared with dogs treated by TCO when it was the primary method used for PDA treatment (1999-2003). Dogs treated during the transition between techniques, dogs treated with SL (1999-2003) and dogs treated with TCO before 1999, as well as dogs with pulmonary hypertension, or bidirectional or reversed (right-to-left) flow through the PDA were excluded from analysis. RESULTS: Age, weight, gender distribution, and procedure times (P=.43) were similar for both groups. Major complications were more common with SL (12% versus 4.3%; P=.035) whereas minor complications were more common with TCO (12% versus 26%; P=.015). Initial success rate was higher for SL (94%) compared with TCO (84%; P=.027). There was no significant difference in mortality between SL (5.6%) and TCO (2.6%; P=.27). CONCLUSIONS: Both SL and TCO are acceptable PDA treatments with comparable mortality; however, SL was associated with a higher risk of major complications and TCO was associated with a lower initial success rate.  相似文献   
948.
Over a 12-day period, 13 animals in a herd of 110 beef cattle developed ataxia with profound muscle fasciculations progressing to recumbency. Twelve animals (5 adults and 7 calves from 8-10 months of age) died, and 1 cow was euthanized. Hemorrhagic diarrhea occurred in some, but not all, animals. The onset of clinical signs was at least 12 hours after the cattle had gained access to contents of old buildings used for storage, and the majority of deaths occurred within 24 to 48 hours after the onset of clinical signs. Approximately 9 kg of unidentified pellets were found strewn in the barn area where the cattle had been. Autolysis considered more severe than expected for the postmortem interval, suggestive of high body temperature before death, and congestion of body tissues were the only significant findings detected in the cow that was euthanized and submitted for necropsy examination. The clinical history and lack of postmortem lesions were most consistent with toxicity. A toxic level of arsenic (6.18 ppm) was detected in the kidney, and metaldehyde was detected in the liver. The pellets were analyzed and found to contain both arsenic and metaldehyde, consistent with a discontinued molluscicidal product.  相似文献   
949.
Synovial hemangioma was diagnosed in an 8-year-old castrated male Belgian Sheepdog with lameness of 3 months' duration. Pain, soft-tissue swelling, and hemarthrosis were localized to the left stifle joint. Projections of synovial membrane with reddish-purple nodules, excised via arthrotomy, were composed histologically of variably sized vascular channels that were lined by well-differentiated endothelial cells and separated by fibrous septa. Distension of some channels resulted in endothelial disruption, thrombosis, hemorrhage, necrosis, and focal spindle-cell proliferation. The limb was amputated to remove remaining neoplastic tissue. The hemangioma extended focally into the joint capsule and popliteal soft tissue but did not invade skeletal muscle or bone. The dog was free of detectable neoplasia 6 months after amputation. Synovial hemangioma is a rare benign vascular proliferation in people, most commonly in the knee, and should be included in the differential diagnosis for canine synovial tumors.  相似文献   
950.
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