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951.
952.
1. The effects of light source and intensity on leg health and performance of female ROSS 308 broiler chickens were investigated in a 2 x 2 experimental design (8 groups of 275 chicks) of two light sources (Osram biolux and Osram warm-white) and two light intensities (5 and 100 clux, adjusted to fowl-perceived illuminance). 2. At 41 d of age, body weight, gait-score, footpad dermatitis and hock-burn were measured on 50 birds from each light environment. In addition, weekly feed intake and body weight were determined on a group basis and mortality was recorded continuously. 3. The light environment did not affect the severity of the gait-score or hock-burns. The risk of moderate to severe lameness and hock-burns increased with body weight. Birds weighing more than 2400 g had an increased probability of moderate footpad lesions in biolux light. 4. Weight and gait-score, as well as gait-score and hock-burn were positively correlated. Podo-dermatitis was weakly correlated with hock-burn, which contradicts earlier findings. The light environment did not affect feed intake, body weight or mortality. 5. The light sources and intensities employed in this study did not adversely affect production or leg health of broiler chickens reared semi-commercially.  相似文献   
953.
BACKGROUND: Identification and control of infections are important in the management of diabetic cats. Urinary tract infections have not been well characterized in diabetic cats. This retrospective study was performed to review and characterize urinary tract infections in diabetic cats. HYPOTHESIS: Urinary tract infections are common in diabetic cats. ANIMALS: A review was made of the medical records of 141 diabetic cats that had had urine obtained for culture by antepubic cystocentesis and that had not been treated with antibiotics, undergone urinary tract catheterization or urinary tract surgery within 2 weeks of urine collection or had urethral obstruction at the time of urine collection. METHODS: A review of medical records. RESULTS: Urinary tract infection was identified in 18 of 141 diabetic cats. Escherichia coli was the most common isolate (67%). Female cats were at increased risk (prevalence odds ratios [POR], 3.7; 95% confidence interval [CI], 1.3 to 10.2; P = .013). Clinical signs of lower urinary tract disease and findings on urine sediment examination were good predictors of positive urine cultures. CONCLUSIONS AND CLINICAL IMPORTANCE: Urinary tract infections are common in diabetic cats regardless of status of diabetic control, suggesting routine monitoring with urine sediment exams or urine culture is warranted.  相似文献   
954.
Rare cases of thymic granulomatous lesions were found in pigs. The lesions consisted of epithelioid cells, multinucleated giant cells, and lymphocytes. Such lesions also were observed in the mesenteric lymph nodes, spleen, kidney, and stomach. The cytoplasm of the majority of giant cells and some epithlioid cells was periodic acid-Schiff (PAS) positive. All cells were positive for vimentin, lysozyme, and desmin. Ultrastructurally, the giant cells were rich in organella and attached to adjacent epithelioid cells by membrane interdigitation. The cells included numerous coated vesicles and granules. No etiologic pathogen, including porcine circovirus type 2, was detected in the lesions. This is the rare case of idiopathic thymic granulomatous lesion in pigs.  相似文献   
955.
Bovine tuberculosis (TB) in cattle is a major economic problem in Britain. In the past 25 years, the infection has been concentrated in the southwest region of England. We investigated the effects of agricultural and farm-management characteristics on the occurrence and scale of TB in cattle in the region (1988-1996) using logistic and linear regression. Factors relating to the existence of previous infection in cattle and the management of cattle and badgers are all linked to the incidence of the infection--but those related specifically to the management of cattle are of overriding importance in determining the scale of the problem. Although our analysis was conducted at a large spatial scale, the results suggest that improvements to the procedure for testing and managing TB in cattle, reductions in cattle stocking density, a greater human input in herd management and more-carefully targeted badger culling all might contribute to reducing the incidence and/or number of herd breakdowns.  相似文献   
956.
Hyperadrenocorticism in ferrets is usually associated with unaltered plasma concentrations of cortisol and adrenocorticotropic hormone (ACTH), although the urinary corticoid/creatinine ratio (UCCR) is commonly elevated. In this study the urinary glucocorticoid excretion was investigated in healthy ferrets and in ferrets with hyperadrenocorticism under different circumstances. In healthy ferrets and in one ferret with hyperadrenocorticism, approximately 10% of plasma cortisol and its metabolites was excreted in the urine. High-performance liquid chromatography (HPLC) revealed one third of the urinary corticoids to be unconjugated cortisol; the other peaks mainly represented cortisol conjugates and metabolites. In 21 healthy sexually intact ferrets, the UCCR started to increase by the end of March and declined to initial values halfway the breeding season (June). In healthy neutered ferrets there was no significant seasonal influence on the UCCR. In two neutered ferrets with hyperadrenocorticism the UCCR was increased, primarily during the breeding season. In 27 of 31 privately owned ferrets with hyperadrenocorticism, the UCCR was higher than the upper limit of the reference range (2.1 x 10(-6)). In 12 of 14 healthy neutered ferrets dexamethasone administration decreased the UCCR by more than 50%, whereas in only 1 of the 28 hyperadrenocorticoid ferrets did the UCCR decrease by more than 50%. We conclude that the UCCR in ferrets primarily reflects cortisol excretion. In healthy sexually intact ferrets and in ferrets with hyperadrenocorticism the UCCR increases during the breeding season. The increased UCCR in hyperadrenocorticoid ferrets is resistant to suppression by dexamethasone, indicating ACTH-independent cortisol production.  相似文献   
957.
958.
959.
OBJECTIVE: To determine concentrations of excitatory and inhibitory amino acids in CSF of a large number of dogs with idiopathic epilepsy or genetic epilepsy and to evaluate changes in CSF amino acid concentration with regard to drug treatment and sex. ANIMALS: 35 Labrador Retrievers with genetic epilepsy (20 male and 15 female), 94 non-Labrador Retrievers with idiopathic epilepsy (71 male and 23 female), and 20 control dogs (10 male and 10 female). PROCEDURE: Collection of CSF was performed > 72 hours after the occurrence of seizures. Cerebrospinal fluid concentrations of gamma-aminobutyric acid (GABA), glutamate (GLU), aspartate (ASP), serine, and glycine were determined by use of high performance liquid chromatography with electrochemical detection. RESULTS: CSF concentrations of GABA and GLU were significantly lower in Labrador Retrievers with genetic epilepsy (LR-group dogs) than in control-group dogs or in non-Labrador Retrievers with idiopathic epilepsy (non-LR-group dogs). The GLU-to-GABA ratio was significantly higher in LR-group dogs than in non-LR-group dogs. CSF concentrations of GLU and ASP were significantly lower when all dogs with epilepsy (non-LR- and LR-group dogs combined) were compared with control-group dogs. CONCLUSIONS AND CLINICAL RELEVANCE: A decrease in CSF concentrations of GABA appears to play a role in the pathogenesis of genetically determined epilepsy in Labrador Retrievers. However, this decrease in CSF concentrations of GABA may also be a consequence of seizure activity. The GLU-to-GABA ratio may prove to be a useful indicator of genetic epilepsy in Labrador Retrievers.  相似文献   
960.
The ability of dual-energy X-ray absorptiometry (DXA) to measure bone mineral content and density of bird bones has received little attention. This paper represents the first comprehensive study of the methods, precision, and reproducibility of DXA (GE-Lunar DPX-L) for the uniquely shaped, thin and pneumatic bones of birds. Skeletal elements and portions represented by 26 regions of interest (ROIs) are presented and evaluated for the gallinaceous bird species, wild turkey (Meleagris gallopavo), ruffed grouse (Bonasa umbellus) and bobwhite quail (Colinus virginianus). Using Lunar small animal software and the methods described in this paper, photodensitometry of bird bones is possible and opens new opportunities for using birds in clinical models in veterinarian science, osteoporosis studies, space biology, and even archaeological and paleontological research.  相似文献   
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