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621.
622.
Background: Retinol-binding protein (RBP) is suggested as a clinically useful marker of renal function in cats.
Hypothesis: Serum and urinary RBP concentrations in hyperthyroid (HT) cats differ from those in healthy (H) cats; radioiodine (131I) treatment influences serum and urinary RBP concentrations in HT cats.
Animals: Ten HT and 8 H cats.
Methods: RBP concentration was evaluated in feline serum and urine samples from a prospective study.
Results: There was a significant ( P = .003) difference in the urinary RBP/creatinine (uRBP/c) ratios of H (−) and untreated HT (1.4 ± 1.5 × 10−2 μg/mg) cats. Serum total thyroxine concentration (1.8 ± 1.9 μg/dL, 24 weeks) and uRBP/c (0.6 ± 1.0 × 10−2 μg/mg, 24 weeks) decreased significantly ( P < .001) in HT cats at all time points after treatment with 131I, and these variables were significantly correlated with one another ( r = 0.42, P = .007). Serum RBP concentrations from HT cats (199 ± 86 μg/L) did not differ significantly ( P = .98) from those of H cats (174 ± 60) and did not change after treatment with 131I (182 ± 124 μg/L, P = .80).
Conclusion and Clinical Importance: The presence of urinary RBP in HT cats is a potential marker of tubular dysfunction that is correlated to thyroid status, although it is independent of circulating RBP concentrations. The decreased uRBP/c combined with the absence of changes in serum RBP after treatment suggests that the suspected tubular dysfunction was partly reversible with treatment of 131I.  相似文献   
623.
The aim of this study was to determine the electrocardiographic characteristics of whippets and to compare the results with published reference values for a general dog population. Electrocardiographic parameters from 105 healthy whippets were used to establish reference values for the breed.The most important differences compared to published reference values were the higher median R-wave amplitudes in leads II, CV6LL and CV6LU. For some parameters (P-wave amplitude, ST-segment deflection and T-wave amplitude in lead II; R-wave amplitude in CV5RL), a marked percentage of the whippet values were above the published maximum reference data. The results confirmed that whippets have electrocardiographic characteristics similar to those reported in athletic heart syndrome in humans. Some of these characteristics could be erroneously taken as evidence of cardiac disease and clinicians should be aware of these factors to prevent unnecessary investigations in healthy dogs.  相似文献   
624.
625.
Live weight is an important trait in cattle farming. Weighing is not always feasible and therefore live weight is often estimated from easily accessible data. In this study, data on live weight, age and gender, and four body measurements, withers height (WH), heart girth (HG) and width of the shoulders (SW) and hind quarters (BcW) of double-muscled Belgian Blue beef (DM-BBB) farm animals were used to develop multivariable non-linear and linear regression models that predict live weight from these easily accessible data. The relationship between the logarithm of the live weight and the logarithm of time is adequately described by a general logistic function. The age period from 100 to 600 days of age is contained in the linear part of the logistic function. This region is of particular economic interest because it contains the yearling age and slaughter age that are important in DM-BBB breeding and management. Adding one of the body traits in the linear models that contain age and gender as fixed effects decreases the coefficient of variation. A model with withers height and shoulder width has the lowest coefficient of variation, with no further significant improvement when adding either heart girth or width of the hind quarters.  相似文献   
626.
During previous work Schistosoma antibodies and circulating antigens were detected at birth in the serum from some calves born to Schistosoma mattheei infected mothers. The objectives of the present survey were: (1) to investigate the proportion of calves, born to cows infected with S. mattheei, which have specific antibodies and circulating schistosome antigens present in their serum at birth and (2) to investigate whether the presence or absence of these specific antibodies and/or circulating antigens at birth may affect the pattern of a natural S. mattheei infection in calves from 4 to 5 months of age, when the colostral antibodies are thought to be of negligible importance. A total of 28 calves born to infected mothers were randomly selected. Faeces, serum and colostrum samples were collected from the cows at calving, serum samples were collected from the calves at birth (day 0), after intake of colostrum (day 1) and monthly thereafter up to the age of 10 months. Both serum and colostrum samples were analysed for IgG(H+L) against SWAP mattheei and schistosome circulating anodic antigen (CAA) levels. The calves were exposed to a natural challenge from the age of 4-5 months. Faecal samples were collected from the calves monthly, starting at an age of 5 months up to 10 months, and were examined for faecal egg counts. Nine (group 1) out of the 28 calves were found to have specific antibodies in their serum at birth, in 5 of them CAA levels were also detected. In the other 19 calves (group 2) no IgG(H+L) or CAA were detected. At the end of the study faecal egg counts and CAA levels were significantly lower in calves from group 1 compared to group 2. Results confirm earlier work that specific antibodies and circulating antigens may be present in serum from calves at birth, and show that these calves have lower faecal egg counts and CAA levels after exposure to a natural challenge.  相似文献   
627.
OBJECTIVES: To describe an open, beating heart surgical technique and use of a bovine pericardial prosthetic valve for mitral valve replacement (MVR) in the dog. STUDY DESIGN: Clinical case report. ANIMALS: Male Bull Terrier (17-month-old, 26 kg) with mitral valve dysplasia and severe regurgitation. METHODS: A bovine pericardial bioprosthesis was used to replace the mitral valve using an open beating heart surgical technique and cardiopulmonary bypass. RESULTS: Successful MVR was achieved using a beating heart technique. Mitral regurgitation resolved and cardiac performances improved (left ventricular end-diastolic diameter decreased from 57.6 to 48.7 mm, and left atrium/aorta ratio returned to almost normal, from 1.62 to 1.19). Cardiopulmonary by-pass time and total surgical duration were decreased compared with standard cardioplegic techniques. Surgical recovery was uneventful and on echocardiography 6 months later valve function was excellent. CONCLUSION: Considering the technique advantages (no cardiac arrest, ischemic reperfusion injury, and hypothermia, or the need for aortic dissection and cannulation for administration of cardioplegic solution), short-term mortality and morbidity may be reduced compared with standard cardioplegic techniques. CLINICAL RELEVANCE: Based on experience in this dog, beating heart mitral valvular replacement is a seemingly safe and viable option for the dog and bovine pericardial prosthesis may provide better long-term survival than mechanical prostheses.  相似文献   
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