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71.
OBJECTIVE: To evaluate the local analgesic effect of ketamine in a palmar digital nerve block at the base of the proximal sesamoid (abaxial sesamoid block) in horses. ANIMALS: 36 mature healthy Andalusian horses. PROCEDURE: Horses were randomly assigned to 4 groups of 9 horses each and received an abaxial sesamoid block in a randomly chosen forelimb with 1 of the following: saline (0.9% NaCl) solution, 1% ketamine solution, 2% ketamine solution, or 3% ketamine solution. To determine analgesia, the radiant heat lamp-hoof withdrawal model was used as a noxious thermal stimulus. Before each nerve block, baseline hoof withdrawal reflex latency (HWRL, time between lamp illumination and withdrawal of the hoof) was determined; after the nerve block, local analgesic effects were determined by measuring HWRL at 2 and 5 minutes after injection and then every 5 minutes for a total period of 1 hour. RESULTS: Significant differences in HWRL were found between baseline values and values at 2 to 15 minutes following a nerve block with ketamine. Significant differences were found between HWRL values at every time point from 2 to 10 minutes following a nerve block with saline solution, compared with 1 or 2% ketamine solution. Similarly, significant differences were found between HWRL values at every time point from 2 to 15 minutes following a nerve block with saline solution, compared with 3% ketamine solution. CONCLUSIONS AND CLINICAL RELEVANCE: Abaxial sesamoid block with ketamine ensures adequate analgesia in horses with an onset of action of 2 minutes and a maximal duration of action of 15 minutes.  相似文献   
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OBJECTIVE: To determine whether passive transfer of IgG in neonatal kittens affects plasma opsonic capacity and neutrophil phagocytic and oxidative burst responses to bacteria in vitro. ANIMALS: 22 kittens from 6 specific pathogen-free queens. PROCEDURE: Kittens were randomized at birth into the following treatment groups: colostrum-fed, colostrum-deprived, or colostrum-deprived supplemented with feline or equine IgG. Blood samples were collected at intervals from birth to 56 days of age. Plasma IgG concentrations were determined by radial immunodiffusion assay. Neutrophil function was assessed by a flow cytometry assay providing simultaneous measurement of bacteria-induced phagocytosis and oxidative burst. The opsonic capacity of kitten plasma was determined in an opsonophagocytosis assay with bacteria incubated in untreated or heat-inactivated plasma. RESULTS: Among treatment groups, there were no significant differences in neutrophil phagocytic and oxidative burst responses to bacteria or opsonic capacity of plasma. In all samples of plasma, inactivation of complement and other heat-labile opsonins significantly reduced the opsonic capacity. Plasma IgG concentrations in kittens did not correlate with neutrophil function or plasma opsonic capacity before or after inactivation of complement. CONCLUSIONS AND CLINICAL RELEVANCE: The plasma opsonic capacity and neutrophil phagocytic and oxidative burst responses in vitro of kittens receiving passive transfer of IgG via colostrum intake or IgG supplementation and those deprived of colostrum were similar. The alternate complement pathway or other heat-labile opsonins may be more important than IgG in bacterial opsonization and phagocytosis.  相似文献   
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A multicenter, prospective study was performed to document the incidence of defective gloves postoperatively in veterinary surgery and to correlate defects with a variety of influencing factors. Gloves were collected after surgical procedures performed by the small animal clinical services at two veterinary teaching hospitals and one institution's student surgery laboratories. Gloves were evaluated for defects using electrical resistance testing. The overall incidence of glove defects was 23.3%. Significantly more defects occurred in gloves used for nonsoft-tissue procedures and in gloves worn on the nondominant hand. Eighty-four percent of all defects occurred in procedures lasting >60 minutes. No differences were detected in the brands of gloves used nor among surgeons of different experience levels. The individuals performing the surgery were not able to accurately predict the presence of a defect in their gloves. Surgeons should remain alert for possible glove defects and consider measures such as changing gloves every 60 minutes or double-gloving to minimize potential complications.  相似文献   
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OBJECTIVE: To compare plasma and synovial fluid endothelin-1 (ET-1) and nitric oxide (NO) concentrations in clinically normal horses and horses with joint disease. ANIMALS: 36 horses with joint disease, and 15 horses without joint disease. PROCEDURE: Horses with joint disease were assigned to 1 of the 3 groups (ie, synovitis, degenerative joint disease [DJD], or joint sepsis groups) on the basis of findings on clinical and radiographic examination and synovial fluid analysis. Endothelin-1 and NO concentrations were measured in plasma from blood samples, collected from the jugular vein and ipsilateral cephalic or saphenous vein of the limb with an affected or unaffected joint, as well as in synovial fluid samples obtained via arthrocentesis from the involved joint. RESULTS: Plasma ET-1 concentrations between affected and unaffected groups were not significantly different. Median concentration and concentration range of ET-1 in synovial fluid obtained from the joint sepsis group (35.830 pg/mL, 7926 to 86.614 pg/mL; n = 7) were significantly greater than values from the synovitis (17.531 pg/mL, 0.01 to 46.908 pg/mL; 18), DJD (22.858 pg/mL, 0.01 to 49.990 pg/mL; 10), and unaffected (10.547 pg/mL, 0.01 to 35.927 pg/mL; 10) groups. Plasma and synovial fluid NO concentrations between affected and unaffected groups were not significantly different. CONCLUSIONS AND CLINICAL RELEVANCE: Endothelin-1 is locally synthesized in the joints of horses with various types of joint disease. Synovial fluid concentrations of ET-1 varied among horses with joint disease, with concentrations significantly higher in the synovial fluid of horses with joint sepsis. These results indicate that ET-1 may play a role in the pathophysiologic mechanism of joint disease in horses.  相似文献   
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Effect of lameness on milk yield in dairy cows   总被引:1,自引:0,他引:1  
OBJECTIVE: To examine the relationship between lameness and milk yield in dairy cows. DESIGN: Cohort study. ANIMALS: 531 dairy cows. PROCEDURE: Cows affected with lameness were classified into 1 of 3 groups on the basis of type of diseases or lesions observed, including interdigital phlegmon (foot rot), papillomatous digital dermatitis (foot warts), or claw lesions. Cows not affected with lameness were classified as healthy. From Dairy Herd Improvement Association records, 305-day mature equivalent milk yield data were collected at the end of lactation or when the cow left the herd. Milk yield was compared between cows affected with lameness and healthy cows. RESULTS: 167 (31%) cows were affected with lameness during lactation. Lame cows had claw lesions (60%), papillomatous digital dermatitis (31%), or interdigital phlegmon (9%). Milk yield in lame cows with interdigital phlegmon (mean, 17,122 lb) was significantly less, compared with healthy cows (19,007 lb). CONCLUSIONS AND CLINICAL RELEVANCE: In this herd, interdigital phlegmon was associated with a 10% decrease in milk production. Lame cows with claw lesions or papillomatous digital dermatitis produced less milk than healthy cows, but the difference was not significant.  相似文献   
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A grazing experiment, conducted for 90 days compared the effect of polyethylene glycol (PEG) supplementation on postpartum reproductive traits and productivity of suckling goats grazing Acacia cyanophylla Lindl. A total of 54 native adult goats (34.4 ± 5.49 kg) were randomly allocated, 24 h after kidding, to 2 treatment groups balanced for age and the number of reared kids. Goats in both treatment groups designed C and PEG grazed in acacia for approximately 5 h every day and received each on daily basis 0.3 and 0.4 kg of hay and concentrate respectively. In addition, goats in treatment PEG were initially supplemented with 10 g/day of PEG and this supplement was then increased to 20 g /goat/day over the last 60 days of the trial. Goats receiving PEG tended (P > 0.05) to spend more time browsing acacia than those in treatment C. There were no treatment effects on live weight change of the goats, growth of their kids until 90 days of age or composition of their milk in terms of fat, protein and urea contents. Similar proportions of 74.1 and 77.8% of goats resumed postpartum ovulation with a mean ovulation rate of 1.50 ± 0.61 and 1.67 ± 0.47 (P > 0.05) in respectively the PEG and C treatments. PEG supplementation was associated with an increase (P < 0.05) in ovulation rate at the second postpartum ovulation occurring approximately 27 days after the application of the nutritional treatments (1.76 ± 0.60 versus 1.25 ± 0.45); 9 of the 13 goats ovulating in the PEG treatment were bearing more than one corpus lutuem in comparison to only 3 out of 12 females in the C group (P < 0.05). The likely increased availability of proteins in the PEG receiving goats could explain their higher ovulation rate.  相似文献   
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