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OBJECTIVE: To determine long-term results and complications of gonadectomy performed at an early age (prepubertal) or at the traditional age in dogs. DESIGN: Cohort study. ANIMALS: 269 dogs from animal shelters. PROCEDURE: Dogs that underwent gonadectomy were allotted to 2 groups on the basis of estimated age at surgery (traditional age, > or =24 weeks old; prepubertal, < 24 weeks old). Adoptive owner information was obtained from shelter records, and telephone interviews were conducted with owners to determine physical or behavioral problems observed in the dogs since adoption. Follow-up information was obtained from attending veterinarians for dogs with complex problems or when owners were uncertain regarding the exact nature of their dog's problem. RESULTS: Prepubertal gonadectomy did not result in an increased incidence of behavioral problems or problems associated with any body system, compared with traditional-age gonadectomy, during a median follow-up period of 48 months after gonadectomy. Rate of retention in the original adoptive household was the same for dogs that underwent prepubertal gonadectomy as those that underwent traditional-age gonadectomy. Infectious diseases, however, were more common in dogs that underwent prepubertal gonadectomy. CONCLUSIONS AND CLINICAL IMPLICATIONS: With the exception of infectious diseases, prepubertal gonadectomy may be safely performed in dogs without concern for increased incidence of physical or behavioral problems during at least a 4-year period after gonadectomy.  相似文献   
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Risk factors for equine laminitis were examined in a prospective case-control study of the 258 cases seen at six collaborating veterinary teaching hospitals over a 32-month period. Case-control pairs were matched on institution, clinician, and season of diagnosis. The 90% of case-control pairs (78 acute, 155 chronic) that had complete data for age, gender, and breed were used in separate conditional logistic-regression models for acute and chronic laminitis. There was an increase in risk for horses with acute laminitis from 5 to 7 years of age (OR 4.7, 95% CI 1.3–16) and from 13 to 31 years of age (OR 3.9, 95% CI 1.3–12) (both compared to <5 years); risk was increased for chronic laminitis from 10 to 14 years (OR 3, 95% CI 1.4–6.8) and from 15 to 38 years (OR 2.9, 95% CI 1.4–6.1) (both compared to <6 years). Mares — but not stallions — were more likely than geldings to develop acute laminitis (OR 2.6, 95% CI 1.1–6.2) and chronic laminitis (OR 2.0, 95% CI 1.1–3.6). In the small acute-laminitis data set, the breed variable was collapsed into three categories: Thoroughbred (THB, reference), the Quarter Horse (QH), and other (non-QH-THB). The non-QH-THB group was at increased risk of acute laminitis (OR 3.8, 95% CI 1.2–11.8). For the seven breed-group categories used in the chronic-laminitis model, however, all non-THB breed groups appeared significantly at risk as compared to the THB, with odds ratios ranging from 3.3 (95% CI 1.3–8.30) for the QH to 9.1 (95% CI 2.1–39.3) for ponies.  相似文献   
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The objective of this study was to assess post-gastric processing of octanoic acid (OA) by comparing the rate of recovery of 13C in breath with the rate of recovery of 2H in saliva following ingestion of [2H/13C]OA. A test meal with 100mg [13C]OA and 750 mg [2H]OA was ingested on two separate occasions by one dog. Exhaled breath and saliva samples were collected at set time points for 6h following ingestion of the test meal. Two indices were computed, half recovery time (t(1/2)) and the time of peak excretion (t(max)). Recovery of 2H in saliva was quicker than recovery of 13C in breath as determined by the difference in the indices for each isotope; 1.33 and 1.59 h for t(1/2) and t(max), respectively. These findings suggest that the post-gastric processing of OA imposes a delay on the recovery of 13C in breath in the dog, as occurs in man and in the horse.  相似文献   
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OBJECTIVE: To determine prevalence of FeLV infection and serum antibodies against feline immunodeficiency virus (FIV) in unowned free-roaming cats. DESIGN: Cross-sectional serologic survey. ANIMALS: 733 unowned free-roaming cats in Raleigh, NC, and 1,143 unowned free-roaming cats in Gainesville, Fla. RESULTS: In Raleigh, overall prevalence of FeLV infection was 5.3%, and overall seroprevalence for FIV was 2.3%. In Gainesville, overall prevalence of FeLV infection was 3.7%, and overall seroprevalence for FIV was 4.3%. Overall, FeLV prevalence was 4.3%, and seroprevalence for FIV was 3.5%. Prevalence of FeLV infection was not significantly different between males (4.9%) and females (3.8%), although seroprevalence for FIV was significantly higher in male cats (6.3%) than in female cats (1.5%). CONCLUSIONS AND CLINICAL RELEVANCE: Prevalence of FeLV infection and seroprevalence for FIV in unowned free-roaming cats in Raleigh and Gainesville are similar to prevalence rates reported for owned cats in the United States. Male cats are at increased risk for exposure to FIV, compared with female cats.  相似文献   
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A case-control study examining diet and lifestyle variables to generate hypotheses of potential risk factors for chronic renal failure in pet cats was conducted in five private practices in Texas, USA and at the Texas A&M University Veterinary Medical Teaching Hospital. A telephone questionnaire was used to gather information from owners of 38 cats newly diagnosed with CRF between December 1994 and 1995 and from owners of 56 control cats. Factor analysis was used to determine whether composite variables should be constructed to summarize the nutritional predictors adequately. The composite variables and other lifestyle variables were analyzed with logistic-regression. Three final exploratory models were developed: ad libitum feeding with fiber; ad libitum with Factor-2 (a composite variable composed of fiber, magnesium, protein, sodium and ash); and fiber alone. Ad libitum feeding and increased ash intake were associated with increased odds of CRF; increased dietary fiber, magnesium, protein and sodium were associated with decreased odds of CRF.  相似文献   
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In samples collected from 170 dogs suspected of having hepatobiliary disease, preprandial serum bile acids (PRSBA) and postprandial serum bile acids (POSBA) concentrations were measured, using a spectrophotometric enzymatic method. Dogs were assigned to 8 disease groups and 1 control group on the basis of hepatic histopathologic findings. Pre- and postprandial SBA concentrations and results of routine biochemical analyses (including total bilirubin, albumin, and BUN concentrations, and serum alkaline phosphatase (ALP), alanine transaminase (ALT), and aspartate transaminase (AST) activities) were expressed, using 4 indices: sensitivity, specificity, positive predictive value, and negative predictive value. Single tests and combinations of tests in series were evaluated. For diagnosis of hepatobiliary disease, the specificity of PRSBA was 100% at values greater than 20 mumol/L and of POSBA was 100% at values greater than 25 mumol/L. Test combinations with the best sensitivity for diagnosing the following diseases were: PRSBA-POSBA for cirrhosis, portosystemic vascular anomaly, and glucocorticoid hepatopathy; PRSBA-POSBA or PRSBA-ALP for cholestasis; PRSBA-POSBA or ALT-AST for chronic hepatitis; PRSBA-ALT for hepatic necrosis and passive congestion; and PRSBA-ALP for neoplasia. Test combinations with the overall highest sensitivity and positive predictive value for the fewest number of tests were PRSBA-POSBA, and either PRSBA or POSBA combined with an enzyme activity (ALT, AST, or ALP). The overall test efficacy for PRSBA vs POSBA was nearly identical: for PRSBA, it was 82.4%, and for POSBA, it was 82.3%. On the basis of the results of this study, PRSBA greater than 20 mumol/L or POSBA greater than 25 mumol/L (measured by use of an enzymatic procedure) indicates histopathologic abnormalities of the hepatobiliary system or portosystemic vascular anastomosis. Seemingly, determination of SBA concentrations can be used to indicate the propriety for hepatic biopsy. Pre- and postprandial serum bile acids concentrations should be evaluated in conjunction with routinely used hepatobiliary screening tests for best diagnostic advantage.  相似文献   
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The NeuroScope, a specific and sensitive indicator of cardiac vagal tone, was used to look for differences in autonomic tone between 25 dogs with naturally occurring diabetes mellitus and 23 healthy control dogs, to determine whether there was any correlation between the dogs' cardiac vagal tone, the duration of diabetes and the adequacy of glycaemic control. The cardiac index of parasympathetic activity (cipa) was determined for each dog over a period of 2600 heartbeats. The mean, median and modal cipa values were significantly lower in the diabetic dogs than in the healthy dogs. There was no significant relationship between the cipa values and the duration of disease or the adequacy of recent glycaemic control in the diabetic dogs, but there was a significant inverse relationship between the cipa values and the bodyweight of the diabetic dogs that was not evident in the normal dogs. The conclusions were based on a 500-heartbeat interval selected from the 2600 heartbeats recorded.  相似文献   
10.
When Tribolium confusum pupae were exposed continuously to temperatures from 10 degrees C to 40 degrees C, the adults which finally emerged exhibited wing abnormalities typical of those obtained with x-irradiation. The data indicate the implication of two processes. Two mathematical models are suggested to account for this phenomenon.  相似文献   
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