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991.
Three cases of discospondylitis in the dog, caused respectively by Pseudomonas aeruginosa, Enterococcus faecalis and Staphylococcus epidermidis, are reported. These bacteria have not previously been documented as being the cause of the condition in this species. The neurological involvement was severe in all three cases. Two dogs were paraplegic and one was tetraplegic, and one of the paraplegic dogs had no deep pain on the extremities of both pelvic limbs. All dogs were treated surgically with a satisfactory neurological recovery.  相似文献   
992.
This study describes longitudinal changes in serum levels of biochemical markers of bone cell activity in a group of 24 thoroughbred foals from birth to 18 months of age. The markers of bone formation included the type I collagen carboxy-terminal propeptide (PICP), the bone-specific isoenzyme of alkaline phosphatase (BAP), and osteocalcin (OC). Levels of the cross-linked telopeptide of type I collagen (ICTP), a marker of bone resorption, and the N-terminal propeptide of type III collagen (PNIIIP), a marker of soft tissue turnover, were also measured. Levels of all markers fell significantly between birth and 18 months of age (70-80 per cent); this decrease being most marked between 0 and 6 months. However, a transient increase in levels of the markers then occurred between 6 and 14 months of age. The timing of this increase was specific for each parameter. ICTP and OC concentrations increased between October and December. PICP concentrations increased between December and April whereas the increase in PIIINP was coincident with the peak in weight gain between April and June. Changes in BAP concentration were less distinct at this time. Season was shown to have significant effects on the biochemical markers independent from the effect of age. Concentrations of all markers decreased with increasing body weight and at any given age heavier horses had lower marker levels. These results show that biochemical markers of bone cell activity and soft tissue turnover follow characteristic patterns of change in growing thoroughbreds influenced by age, season and bodyweight. The demonstration that the reference ranges for the biochemical markers change from month to month means that single samples from individuals are of little value for monitoring bone cell activity in growing thoroughbreds.  相似文献   
993.
The effects of clenbuterol administered at anabolic doses on the testicular interstitium were studied in 30 pigs allocated to three experimental groups. The diet of two groups was supplemented with clenbuterol (Clb) (1 ppm), but whereas in the Clb+ group the treatment was given until slaughter (treatment period: 3 months), in the Clb- group the clenbuterol was withdrawn 2 weeks before slaughter (treatment period: 2-5 months); in the control group, the pigs were fed without clenbuterol. For histological procedures, a fractional sampling scheme was applied and routine techniques for light and transmission electron microscopy were used. The results of subjective morphology and morphometrics showed slight differences between the treated and the control groups. Conversely, the stereological results identified a prominent hyperplasia of the Leydig cells and ultrastructural analysis of these cells revealed a conspicuous increase in the organelles related to testosterone production, suggesting a functional activation of the interstitial cells in response to the clenbuterol treatment.  相似文献   
994.
Wildlife mortality involving bongos, Tragelaphus eurycerus, and other ungulates was investigated in the north of the Congo Republic in 1997. Four bongos, one forest buffalo, Syncerus caffer nanus, and one domestic sheep were examined and sampled. Although an outbreak of rinderpest had been suspected, it was found that the animals, which had been weakened by an Elaeophora sagitta infection and possibly also by adverse climatic conditions, had been exsanguinated and driven to exhaustion by an unusual plague of Stomoxys omega.  相似文献   
995.
Intradermal injection of a Culicoides antigen extract (CAgX) induces T lymphocyte and eosinophil accumulation in the skin of horses with sweet itch. Blood mononuclear (BMN) cells from normal ponies proliferate when stimulated by mitogen (phytohaemagglutinin, PHA) or antigen (tetanus toxoid, TT) and, as shown here, release soluble factor(s) that induce eosinophil adherence. CAgX also caused concentration dependent proliferation of BMN cells from sweet itch and normal ponies [stimulation index: 29 (13) and 17 (7) for BMN cells from sweet itch and normal ponies, respectively during the active phase of disease; 4 microg protein ml(-1)CAgX; 168 h]. A heat labile factor(s) which caused eosinophil adherence was also released [sweet itch ponies: 6.0 (1.6) per cent adherence versus 1.3 (0.4) per cent; normal ponies: 6.6 (0.5) per cent adherence versus 0.9 (0.1) per cent for supernatants from CAgX (4 microg protein ml(-1); 48 hours) stimulated versus unstimulated BMN cells, respectively]. These results suggest that soluble proteins released from T lymphocytes could affect eosinophil function in the lesional skin of sweet itch horses.  相似文献   
996.
The prevalence of chronic wasting in cattle in March and April 2000 was studied on 218 dairy farms with a history of health problems accompanied by wasting, following reports in the media suggesting that chronic wasting was a substantial problem on Dutch dairy farms. A telephone call revealed that the health problems had resolved on 41 farms; 16 of these farms had culled all cattle. Two farmers refused co-operation. On the remaining 175 farms the animals were inspected and was completed a questionnaire. A high percentage of culling for of health reasons (on average 18.1% of young stock and adult cattle) and an increased mortality rate (4.8%) were reported on the farms visited. In only two of the 175 inspected herds, more than 20 percent of cattle were found showing signs of wasting. These two herds were identified as 'chronic wasting herds'. The prevalence of such herds was low in this study. Consequently, it is likely that there were very few 'chronic wasting herds' among the whole Dutch dairy population in March/April 2000.  相似文献   
997.
In swine medicine, the determination of hematology and blood chemistry parameters is of primary interest in connection with the detection of herd problems. For the evaluation of laboratory results the availability of reference values is a prerequisite. So far, no reference values of fattening pigs have been available in Switzerland. For this reason, in the present study reference values for hematology and blood chemistry were determined for two bodyweight categories, 40-60 kg (group 1) and 85-110 kg (group 2). Hematocrit, hemoglobin and RBC counts were lower in animals in group 1. The number of segmented neutrophils was markedly higher in group 1. Lymphocyte counts exceeded neutrophil values in both groups. Concentrations of total bilirubin, AST, CK and LDH partly reached very high levels due to hemolysis or contamination of the blood samples with muscle tissue.  相似文献   
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