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191.
Steinbach G Kröll U Meyer H Methner U 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(7-8):281-287
The development of the antibody concentration against lipopolysaccharide (LPS) of S. Typhimurium und S. Choleraesuis in rearing pigs during the fattening period and in breeding sows of the corresponding age was recorded. The studies revealed the following results. Antibodies of isotypes IgG1 and IgG2 revealed a more pronounced specificity against the according Salmonella serovar than IgM antibodies. The calculated "antibody percent value" based on the total amount of Salmonella antibodies is mainly determined by the IgM antibodies in sera and meat juice, respectively. In fattening pigs a significant increase of antibodies against IgM and total Ig was observed between week 3 and 10 after beginning of the rearing period. In breeding pigs this increase was detectable already earlier. In only 3 out of 10 groups an increase of IgG1 and IgG2 was also seen. The detected significant increase of total Ig and IgM in the other groups might be the result of a less intensive exposure to salmonellas or it might be due to an increase of unspecific antibodies induced by other antigens. Serological investigations represent a valuable tool to record the intensity and development in time of the Salmonella exposure in pigs farms. Examination of total Ig is an appropriate method to detect pig herds with a high level of Salmonella exposure, for detailed epidemiological studies in pig farms the examination of antibody isotypes will give more comprehensive information. 相似文献
192.
Nöckler K Kutzer P Reif S Rosenberger N Draeger A Bahn P Göllner C Erlbeck C 《Berliner und Münchener tier?rztliche Wochenschrift》2003,116(9-10):368-372
Brucella (B.) canis was isolated from ejaculate of a 4-year old Korthals-Griffon male dog after occurrence of epididymitis and orchitis. Despite several trials of therapy with different antibiotics relapes occurred, with B. canis being isolated from ejaculate, blood and urine samples, respectively. Bacteriological examinations were added by serological testing over a period of about 1.5 years. During the study SAT serum titre steadily dropped from 1:200 to 1:50. By CFT, B. canis antibodies were detectable at the beginning with a titre of 1:320 and to the end of the study with titres between 1:80 and 1:160. 相似文献
193.
Evidence exists that butyrate inhibits apoptosis of colon crypt cells in vivo so that less tryptophan from cell debris is available for skatole formation by microbes in the pig colon. In this study, potato starch containing a high proportion of resistant starch was fed to test the hypothesis that increased butyrate formation will occur in the colon and contribute to reduced epithelial cell apoptosis, thus leading to reduced skatole formation and absorption. Two groups of six barrows were provided with catheters in the jugular vein and fed either a ration with pregelatinized starch (high ileal digestibility; controls) or potato starch (low ileal digestibility; PS) as the main carbohydrate. All pigs were fed 31 MJ of metabolizable energy and 381 g of crude protein per day. The controls were fed for 19 d. The PS group received the same control ration for 10 d, and then changed to the PS ration. The total feeding period of PS consisted of a 5 d adaptation period followed by another 19 d. In the continously sampled feces, pH, short chain fatty acids, and skatole were determined. Skatole was additionally measured in blood plasma that was sampled daily. After killing barrows at the end of the feeding period, fat tissue for skatole measurement and colon tissue for histological quantification of mitosis and apoptosis were obtained. Feeding potato starch led to a rapid 2.2 fold increase of fecal butyrate when compared both with the control period of the PS group and the control group (P < 0.001). PS feeding resulted in a decrease in pH from 7.3 to 5.3 (P < 0.001) and apoptosis from 2.06 cells/crypt to 0.90 cells (P < 0.01), whereas there was no change in mitosis. Consequently, skatole decreased both in feces (controls vs PS group: 120.0 vs 1.9 microg/g; P < 0.001) and in blood plasma (1.6 vs 0.2 ng/mL; P < 0.001). The mean concentration of skatole in fat tissue was 167 ng/g tissue in controls, and below the detection limit (0.8 ng/g) in the PS group (P < 0.001). It is concluded that butyrate-dependent inhibition of apoptosis in the colon due to potato starch feeding efficiently inhibits skatole production in barrows. Because of the depressed skatole levels, improved sensory quality of pork is possible. 相似文献
194.
The aim of this study was to investigate the effects of two commercially available probiotics, alone and in combination with an antibiotic, on the caecal flora of Japanese quail (Coturnix coturnix japonica) reared under unstressed conditions. Thirty-four 90-day-old Japanese quail were selected for this study. The birds were divided into four groups, two groups of nine birds and two groups of eight birds. The animals in these groups were given feed containing 0.5 kg per tonne of probiotics alone (Protexin or Biosacc), a mixture of probiotic plus antibiotic (Biosacc plus Zinc Bacitracin at 0.5 and 0.0525 ppm, respectively), and a group where no supplement was added to be used as controls. The total count of aerobic bacteria, lactobacilli, enterobacteriaceae, coliforms, enteroccoci, salmonellae, sulphite-reducing anaerobic bacteria (clostridia), and pH values in the caecal content of the birds were examined. No significant differences were detected among the four groups for pH values and bacterial number (p>0.05), except for sulphite-reducing anaerobic bacteria (p<0.001). These results suggest that the use of probiotics alone and/or a mixture of a probiotic plus antibiotic as a feed supplement does not have a major suppressing effect on the majority of bacterial groups in the caecal flora of mature, healthy Japanese quail reared in unstressed conditions. 相似文献
195.
Mischke R Höinghaus R Lütkefels E Buhl K Gerhardt A Hewicker-Trautwein M 《The Journal of small animal practice》2003,44(9):411-414
The case history of a four-year-old, male Bernese mountain dog is presented. Carcinoma cells were detected in the liver by ultrasound-guided fine-needle aspiration. Bone marrow aspirated from the iliac crest and the left femur showed a distinct infiltration by carcinoma cells. Immunocytological examination of the liver and bone marrow metastases showed a negative staining result for large spectrum cytokeratin (CK) KL1, a strong positive result for CK7 and a focal weak positive result for CK20. The dog was euthanased due to the grave prognosis. Histopathological examination revealed metastatic cholangiocarcinoma. The authors conclude that cytological and immunocytological examination of bone marrow aspirates should be used more frequently for the detection of distant metastases of carcinomas in small animal medicine. 相似文献
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An experiment was performed during the grazing seasons of 1998, 1999 and 2000 to study the influence of the antiparasitic drug ivermectin and the nematophagous fungus Duddingtonia flagrans on cattle dung disintegration. The faeces originated from groups of animals that were part of a separate grazing experiment where different control strategies for nematode parasite infections were investigated. Each group consisted of 10 first-season grazing cattle that were either untreated, treated with the ivermectin sustained-release bolus, or fed chlamydospores of D. flagrans. Faeces were collected monthly on 4 occasions and out of pooled faeces from each group, 4 artificial 1 kg dung pats were prepared and deposited on nylon mesh on an enclosed pasture and protected from birds. The position of the new set of pats was repeated throughout the 3 years of the study. Each year, the dung pats were weighed 4, 6, 8 and 10 weeks after deposition and immediately afterwards replaced to their initial positions. Results showed that there was no difference in faecal pat disintegration between groups. However, the time-lag between deposition and complete disintegration of the faeces varied significantly between deposition occasions. Dung pats disappeared within 2 weeks (visual observation) when subjected to heavy rainfall early after deposition, whereas an extended dry period coincided with faeces still remaining 12 months after deposition. 相似文献