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The pathology of Johne''s disease in sheep 总被引:4,自引:0,他引:4
The clinical, gross and histopathological findings in 50 sheep affected with Johne's disease are described. Clinically 90% were emaciated and 20% showed severe diarrhoea. On necropsy there was thickening of the walls of the intestines, particularly of the ileum, caecum and less frequently the jejunum, but in 36% of sheep the changes were only mild. Histologically there was a granulomatous enteritis, typhlitis and colitis, with the most severe changes in the terminal ileum. High numbers of acid-fast organisms were present in the terminal ileum in over 70% of sheep. Mycobacterium paratuberculosis was cultured from only 8% of the sheep examined. 相似文献
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Sorghum ergot produces dihydroergosine (DHES) and related alkaloids, which cause hyperthermia in cattle. Proportions of infected panicles (grain heads), leaves and stems were determined in two forage sorghum crops extensively infected 2 to 4 weeks prior to sampling and the panicles were assayed for DHES. Composite samples from each crop, plus a third grain variety crop, were coarsely chopped and half of each sealed in plastic buckets for 6 weeks to simulate ensilation. The worst-infected panicles contained up to 55 mg DHES/kg, but dilution reduced average concentrations of DHES in crops to approximately 1 mg/kg, a relatively safe level for cattle. Ensilation significantly (P = 0.043) reduced mean DHES concentrations from 0.85 to 0.46 mg/kg. 相似文献
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T Guimarães C Miranda M Pinto E Silva L Damásio AL Costa MJ Correia JC Duarte C Cosinha G Lopes G Thompson A Rocha 《Reproduction in domestic animals》2014,49(6):926-933
A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro‐organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non‐breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro‐organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro‐organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro‐organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro‐organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli. 相似文献
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