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Effective nursery diets can greatly reduce the cost of producing juvenile sea cucumbers for release to aquaculture or restocking programs. However, methods for systematically testing the bioavailability of artificial diet ingredients for sea cucumbers are poorly developed, and consequently, there has been little research in this field. The current study presents methods developed to test the suitability of common carbohydrate and protein sources for inclusion in artificial diets for juvenile Australostichopus mollis. Apparent digestibility of carbohydrates was moderate and did not exceed 50% for any carbohydrates assayed. Wheat starch and carrageenans showed the highest digestibility amongst carbohydrates. Differences in apparent digestibility were not reflected in growth performance of juvenile A. mollis fed carbohydrate diets; overall growth performance was poor for all diets. Artificial protein sources consistently exhibited higher apparent digestibility, ranging from 75.1% for fish meal to 98.1% for casein. Low‐cost protein sources, like meat meal, show promise for future use in artificial diet formulation. However, delivering high protein content may reduce ingestion rates and thereby lower overall digestive efficiency in juveniles. Results show that artificial carbohydrate sources have some potential as diet constituents for juvenile sea cucumbers but are unsuitable as primary energy sources. Future testing of artificial carbohydrate sources for A. mollis may require predigestion to improve digestibility.  相似文献   
3.
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   
4.
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   
5.
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   
6.
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   
7.
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   
8.
9.

Background

Bluetongue virus (BTV) is an insect-transmitted virus, which causes bluetongue disease (BT) in sheep and a fatal hemorrhagic infection in North American white-tailed deer. However, in cattle the disease is typically asymptomatic and no overt clinical signs of disease appear to be associated with BTV infection. Serological evidence and isolation of different BTV serotypes have been reported in Sudan, however, no information is currently available in regard to previous exposure of Sudanese livestock to BTV infection in East Darfur State, Sudan.

Aims

To determine the prevalence of BTV antibodies and to identify the potential risk factors associated with BTV infection among cattle in East Darfur State, Sudan.

Methods

A total of 224 blood samples were collected randomly from five localities in East Darfur State, Sudan. The serum samples were screened for detection of BTV-specific immunoglobulin G (IgG) antibodies using a competitive enzyme-linked immunosorbent assay (c-ELISA).

Results

Serological evidence of BTV infection was observed in 150 out of 224 animals accounting for a 67% prevalence rate among cattle in East Darfur State. Older cattle (>2 years of age) were six times more likely to be infected with BTV (OR = 6.62, CI = 2.87-15.26, p-value = 0.01). Regarding animal source (contact with other herds) as a risk factor, it was shown that cattle purchased from market or introduced from other herds were 3 times at higher risk of being infected with BTV (OR = 3.87, CI = 1.07-13.87, p value = 0.03). Exposure of cattle to the insect vector increased the risk of contracting BTV infection by six times compared to non-exposed cattle (OR = 6.44, CI = 1.53-27.08, p value = 0.01).

Conclusion

The present study indicated that age, animal source and the intensity of the insect vector are influential risk factors for BTV infection in cattle in the Darfur region. Surveillance for BTV infection should be extended to include other susceptible ruminants and to study the distribution of the insect vectors to better predict and respond to a possible BTV outbreak in the State of East Darfur, Sudan.  相似文献   
10.
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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