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991.
From 397 fecal specimens from apparently healthy and from diarrheic pigs, dogs, cats and cattle 59 strains (= 15%) of thermophilic Campylobacter (C.) spp. were isolated by culture. 39 strains were identified as C. coli and 18 as C. jejuni whereas 2 isolates could not be classified. None of the strains was found to be positive for cytotoxic enterotoxin in the GM1-ELISA. In the Vero-cell test 5 isolates showed a cytotoxic effect. The salt aggregation test (SAT) for indicating cell surface hydrophobicity was positive with 24 strains (5 C. jejuni, 19 C. coli). A correlation of isolation results with clinical manifestation could not be observed.  相似文献   
992.
Quantitative pathohistological investigations were performed on 300 samples of five different myocardial regions from 50 pigs with had suffered stress-related myocardial insufficiency on their transport to the slaughterhouse (transport exhaustion). The findings were compared to 1,200 myocardial samples from 200 clinically intact pigs for slaughter. Animals with transport-related damage exhibited with significance more and more severe inflammatory and degenerative myocardial alterations, such as round-cell infiltration, fiber necrosis, calcification, and fat infiltration. Many of these lesions had been manifest already prior to transport. Myocardially predamaged pigs were less capable than others of sustaining transport stress and were more predisposed to cardiac failure. Stress-related cardiovascular insufficiency, consequently, depended not only on direct stress but also on the general health condition of the myocardium. Causes and pathogenetic relevance of these alterations are discussed in some detail.  相似文献   
993.
In three experiments with fattening pigs the supplementation of a ration with 8% rapeseed oilmeal (RSO) with 1 mg J/kg resulted in an increased weight gain per day of 31, 94 and 87%. On the other hand, only 83, 76 and 84% of the weight gain of the soybean oilmeal control groups were achieved. The additional supply with 250 mg Cu (experiments II and III) increased the weight gain to 84 and 96% in comparison to the unsupplemented control groups. The combination of J + Cu + Zn lead to the same performance as that of J + Cu (experiment III). In the RSO groups without J-supplement changes in body proportions and parakeratosis could be observed after approximately equal to 7 weeks. After the sole supplementation of Cu these symptoms occurred approximately equal to 4 weeks later. In vitro, the supplementation of RSO with a CuSO4 solution resulted in a decrease of vinylthiooxazolidon and isothiocyanate in line with the CuSO4-concentration. 0.2 mg J/kg feed (experiment III) resulted in the same fattening performance as the supplementation of the ration with 1 mg J and outwardly visible deficiency symptoms. The results show that Cu, depending on its quota, results in a decrease of goitrogenics in the feed and that J and Cu supplementation to rations with rapeseed oilmeal have an additive effect and that parakeratosis can be prevented by J-supplementation.  相似文献   
994.
In summary, pancreatitis is common in dogs and cats, but it seems that most cases remain undiagnosed. Serum amylase and lipase activities are useful as a quick screening test for pancreatitis in the dog only. Serum amylase or lipase activity must be at least three to five times the upper limit of the reference range to suggest a diagnosis of pancreatitis. Furthermore, the diagnosis must be confirmed by other diagnostic modalities, and normal test results do not eliminate the possibility of pancreatitis. Abdominal ultrasound is highly specific for pancreatitis in dogs and cats but is not particularly sensitive, especially in cats. Serum cPLI concentration is highly specific for exocrine pancreatic function and is also highly sensitive for pancreatitis. Similarly, initial data would suggest that serum fPLI is the most sensitive and specific diagnostic test for feline pancreatitis. Until further data are available, however, serum fPLI should be used in conjunction with other diagnostic tests to arrive at a diagnosis of feline pancreatitis. Histopathologic evidence of pancreatitis is conclusive for a diagnosis of pancreatitis. In most cases, however, lesions are localized, and the lack of histopathologic evidence of pancreatitis does not eliminate a diagnosis of pancreatitis.  相似文献   
995.
Esophageal-pharyngeal fluids from 53 free-ranging marsh deer (Blastocerus dichotomus) captured for a research program in the state of Mato Grosso do Sul, Brazil, were assayed for tuberculosis. Total DNA was extracted. amplified by polymerase chain reaction using specific primers for Mycobacterium tuberculosis complex (M. tuberculosis, M. bovis, M. microti, and M. africanum), and observed by agarose gel electrophoresis stained with ethidium bromide. All samples were negative. This, along with necropsy and histopathology data, suggests that these animals are not shedding and probably do not have active disease.  相似文献   
996.
黄土高原水土保持世行贷款项目区局地气候变化初步分析   总被引:3,自引:1,他引:2  
对黄土高原水土保持世界银行贷款项目实施前后的监测数据和有关气象资料进行分析表明 ,大规模林草、梯田等坡面措施和沟道坝库工程的实施 ,影响了当地小气候特性 ,较好地起到了调节温度、提高湿度、增加降水和雾日、减少冰雹等作用 ,项目区与参照站比较 ,相对湿度提高了 5~ 10个百分点 ,平均每年有雾日相对增加了 6 7d ,年降水量相对增加 5 %~ 10 %。  相似文献   
997.
Two hundred one serum samples from individual dairy cows with a range of results on initial testing with a commercial Johne's disease enzyme-linked immunosorbent assay (ELISA) kit were repeat tested 5 times in each of 2 laboratories with kits produced by the same manufacturer. The results for the samples with all 10 replicates showed that the values for individual samples often had a coefficient of variation greater than 20%. As expected, the standard deviation for the results increased as the average value increased and the coefficient of variation was greater in samples with low mean values. The different lots of the commercial ELISA kit used in this study had a significant effect on both the optical density and the calculated sample to positive (S/P) ratio for test replicates. Based on the variability detected in S/P ratios of replicate samples, application of a single cutoff point to interpret individual test results as positive or negative for antibodies to Mycobacterium avium subspecies paratuberculosis could result in inconsistent classification of animals as positive or negative for Johne's disease. Such inconsistency in test interpretation leads to frustration in large animal veterinarians or producers trying to make management decisions based on individual test results. Instead of dichotomizing the test results as positive or negative based on a single cutoff value, reporting numerical values and supplying a classification scheme that includes a suspect category reflecting the uncertainty inherent in the test is recommended to provide more reliable result interpretation.  相似文献   
998.
木材用脲醛树脂基本适用竹材胶合,但需改善耐水性能;竹席胶合板的静曲强度和脲醛树脂的固体含量及粘度有关,通常随二者增大而增大,粘度过大反而降低,故宜选用固体含量55%、粘度60—80cPa·s、pH7.0的脲醛树脂。  相似文献   
999.
1000.
The castration of the cock is described from the topographic anatomical view. In contrast to previous authors a general narcosis is recommended, which is in accord with the relevant legislation for the prevention of cruelty to animals.  相似文献   
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