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OBJECTIVE: To determine the effect of age on reference intervals of serum biochemical values in kittens. DESIGN: Prospective clinical trial. ANIMALS: 55 kittens from 12 specific-pathogen-free queens. PROCEDURE: Kittens were allocated at birth into colostrum-fed (n = 27) and colostrum-deprived (28) groups. Blood was collected at birth and on days 1, 2, 4, 7, 14, 28, and 56. Serum samples were analyzed for activities of alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, creatine kinase, lactate dehydrogenase, gamma-glutamyltransferase, amylase, and lipase and for concentrations of albumin, total protein, bilirubin, urea nitrogen, creatinine, cholesterol, glucose, calcium, phosphorus, and triglycerides by use of an automated analyzer. Total serum solids concentrations were determined by use of refractometry. Serum IgG concentrations were quantified by use of radial immunodiffusion. RESULTS: For several analytes, reference intervals changed rapidly, most notably during the first few days of life. Reference intervals for alkaline phosphatase, creatine kinase, lactate dehydrogenase, and triglycerides were higher from birth to 8 weeks than adult reference intervals. Aspartate aminotransferase, bilirubin, urea nitrogen, and creatinine were higher than in adults at birth but were similar to or lower than adult reference intervals by 8 weeks. Compared with adult reference intervals, reference intervals for calcium and phosphorus concentrations were higher and for albumin and total protein concentrations were lower throughout the study period. CONCLUSIONS AND CLINICAL RELEVANCE: Important differences exist between reference intervals for serum biochemical values of neonatal and adult cats. Age-appropriate reference intervals should be used for accurate assessment of serum biochemical test results in cats.  相似文献   
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Protective vaccine responses to nine distinct serogroups of Dichelobacter nodosus (serogroups A-I) can be readily measured by serogroup-specific K-agglutinating antibody titres. On the basis of a large quantitative genetic experiment (1200 progeny from 129 sire groups), it was shown that variation in antibody responses following vaccination with a multi-valent pilus antigen D. nodosus vaccine (serogroups A-I) is, in part, under genetic control and thus heritable. Based on the genetic relationships between antibody responses to all nine antigens, results suggested that both genes for a broad-based and genes for serogroup-specific response contributed to genetic variation in vaccine response. Furthermore, preliminary data in 389 progeny showed that polymorphism within the ovine major histocompatibility (MHC) based on serological classification accounted for a significant proportion of the variation in vaccine responses. In subsequent experimentation, we examined the importance of genetic polymorphism within the ovine MHC, and the possibility of genes outside the MHC for their involvement in antigen-specific and broad-based vaccine response. Within two large half sib families(131, and 143 progeny), four MHC haplotypes were investigated and found to be associated with differential antibody responses to six out of eight distinct vaccine-antigens presented to the host in a multi-valent vaccine. The model used here shows how well characterised immunogens, quantitative genetic experimentation, and molecular gene mapping tools can be used to unravel genetic differences in host responses to commercial vaccines.  相似文献   
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OBJECTIVE: To report clinical experience with arthrodesis of the proximal interphalangeal joint in horses using two parallel 5.5-mm cortical bone screws placed in lag fashion. STUDY DESIGN: Retrospective, clinical study. ANIMALS: Thirty-four horses, aged 1 to 19 years. METHODS: Medical records for all horses admitted (1991-1997) for pastern arthrodesis using two 5.5-mm ASIF cortical bone screws, in parallel orientation, and placed in lag fashion by use of a combined aiming device to facilitate accuracy were reviewed. Signalment, lameness diagnosis, duration of lameness, limb(s) involved, and outcome were recorded. Criteria for successful outcome were determined as return to previous level of function or future intended athletic use. RESULTS: Thirty-nine proximal interphalangeal joint arthrodeses were performed on 34 horses. One horse was euthanatized in the recovery room and was excluded from data analysis. Successful outcome occurred in 85% of frontlimbs and 89% of hindlimbs. Failure occurred in 5 joints; 1 horse had lameness directly associated with surgery, whereas 4 horses had unrelated lameness. CONCLUSION AND CLINICAL RELEVANCE: Age, breed, and initial disease did not affect outcome. Arthrodesis of the proximal interphalangeal joint by use of two 5.5-mm ASIF cortical bone screws, in parallel orientation, placed in lag fashion by use of a combined aiming device, resulted in sound use of the limb in >85% of the joints with shortened postoperative coaptation.  相似文献   
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The recruitment patterns of six teleosts were studied at King’s Beach, Algoa Bay. February to May marked the major recruitment period for Diplodus sargus, Lithognathus mormyrus, Rhabdosargus globiceps and Trachurus capensis. The major recruitment of Sarpa salpa fry took place between August and September. Pomadasys olivaceum fry of < 5 cm total length were caught throughout the year indicating an extended breeding period. The estimated growth rates of new recruits between February and May (autumn/winter) was 0,60 cm month -1 for L. mormyrus, 0,75 cm month-1 for ft globiceps and 0,40 cm month-1 for T. capensis. The empirical growth curve derived for S. salpa indicated a growth rate of 0,75 cm month-1. No growth estimates could be made for P. olivaceum or D. sargus.  相似文献   
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A 4-month-old colt with stage I flexural deformity of the distal interphalangeal joint was diagnosed as having a type IV nondisplaced fracture of the extensor process of the 3rd phalanx. An inferior check ligament desmotomy and internal fixation of the fracture were performed. Favorable long-term results for internal fixation of extensor process fractures are presented.  相似文献   
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Three experiments evaluated the lipids in distillers grains plus solubles compared with corn or other sources of lipid in finishing diets. Experiment 1 utilized 60 individually fed yearling heifers (349 +/- 34 kg of BW) fed treatments consisting of 0, 20, or 40% (DM basis) wet distillers grains plus solubles (WDGS), or 0, 2.5, or 5.0% (DM basis) corn oil in a finishing diet based on high-moisture corn (HMC) and dry-rolled corn. Cattle fed 20 and 40% WDGS had greater (P < 0.10) G:F than cattle fed 0% WDGS. Cattle fed the 5.0% corn oil had less overall performance than cattle fed the other diets. Results from Exp. 1 indicated that adding fat from WDGS improves performance, whereas supplementing 5.0% corn oil depressed G:F, suggesting that the fat within WDGS is different than corn oil. Experiment 2 used 234 yearling steers (352 +/- 16 kg of BW) fed 1 of 5 treatments consisting of 20 or 40% (DM basis) dry distillers grains plus solubles, 1.3 or 2.6% (DM basis) tallow, or HMC. All diets contained 20% (DM basis) wet corn gluten feed as a method of controlling acidosis. No differences between treatments for any performance variables were observed in Exp. 2. The dry distillers grains plus solubles may be similar to tallow and HMC in finishing diets containing 20% wet corn gluten feed. Experiment 3 used 5 Holstein steers equipped with ruminal and duodenal cannulas in a 5 x 5 Latin square design. Treatments were a 40% WDGS diet, 2 composites, one consisting of corn bran and corn gluten meal; and one consisting of corn bran, corn gluten meal, and corn oil; and 2 dry-rolled corn-based diets supplemented with corn oil or not. Cattle fed the WDGS diet had numerically less rumen pH compared with cattle fed other treatments. Cattle fed WDGS had greater (P < 0.10) molar proportions of propionate, decreased (P < 0.10) acetate:propionate ratios, greater (P < 0.10) total tract fat digestion, and a greater (P < 0.10) proportion of unsaturated fatty acids reaching the duodenum than cattle fed other treatments. Therefore, the greater energy value of WDGS compared with corn may be due to more propionate production, greater fat digestibility, and more unsaturated fatty acids reaching the duodenum.  相似文献   
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