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61.
T W Fossum W N Evering M W Miller S D Forrester D R Palmer C C Hodges 《Journal of the American Veterinary Medical Association》1992,201(2):317-324
Severe bilateral fibrosing pleuritis was diagnosed in 5 cats and 2 dogs with chronic chylothorax. All animals were dyspneic on initial examination and remained moderately to severely dyspneic after thoracentesis. Radiographic evidence of fibrosing pleuritis included rounded lung lobes and failure of the lungs to reexpand following effective pleural drainage. Fibrosing pleuritis was also suggested in several animals with radiographic evidence of pleural fluid, in which pleural fluid could not be retrieved. Macroscopically, the lung lobes of all animals were compressed and atelectatic to various degrees, and the pleura appeared to be diffusely thickened and roughened. In several animals, fibrous adhesions were found between the parietal and visceral pleura of some lobes. Lung lobes were markedly constricted and appeared as small, smooth, rounded hilar masses in 4 animals. Mild to moderate pulmonary edema was evident in 3 animals at necropsy. Six of the 7 animals died (2) or were euthanatized (4) within 72 hours after the diagnosis of fibrosing pleuritis. The fibrosing pleuritis developed in 1 animal with lymphoblastic lymphosarcoma and chylothorax after treatment via passive pleuroperitoneal drainage; this animal was euthanatized because of underlying neoplasia. One cat, in which decortication was performed and resulted in marked reexpansion of the lung lobes, died 4 hours after surgery with signs compatible with pulmonary edema. On the basis of our findings, we suggest that animals with chronic chylothorax are at risk to develop fibrosing pleuritis. Furthermore, animals with severe bilateral fibrosing pleuritis should be given extremely guarded prognoses. 相似文献
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The copper content of the livers from 347 pigs was analysed. Two hundred and three of these samples were from animals varying in age from full term foetus to five years, which were submitted to the laboratory (laboratory cases) for a variety of diagnostic tests. The remaining 144 liver samples were obtained from pigs slaughtered at an abattoir (abattoir survey) at 75-85 kg liveweight (approximately 20-30 weeks old). Liver copper levels of 12 mg/kg D.M. (Dry Matter) or less, a level consistent with copper deficiency, were found in 6.9% of the laboratory cases and in 9.0% of the abattoir survey pigs. Liver levels less than 20 mg/kg suggesting insufficient dietary copper to produce a growth-promoting effect, were found in 21.6% of the former and 36.1% of the latter pigs. A significantly greater frequency of illthrift and anaemia was found in the laboratory cases in which liver copper levels were less than 20 mg/kg compared with animals with higher levels. Liver copper levels less than 20 mg/kg were also more common in pigs derived from dairy farms or fed garbage than in animals from pig farms or fed on meal. All of 26 samples of commercial pig meal analysed contained sufficient copper to satisfy the daily essential copper requirements of pigs (greater than 5-6 mg/kg) but 14 of these (53.8%) contained less than 125 mg/kg levels of copper and were unlikely to produce a growth-promoting effect. 相似文献
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A commercially manufactured leptospirosis vaccine containing serovars pomona and hardjo and licensed for use in cattle and sheep was investigated to determine if it would prevent leptospiruria in pigs exposed to serovar pomona. Twenty piglets were each vaccinated twice at an interval of three weeks. Twenty other piglets were unvaccinated and served as controls. Three weeks after the second dose of vaccine all animals were exposed for 64 to 89 days to a natural infection with pomona. During the investigation blood samples were examined serologically and urine samples were examined by dark ground microscopy and cultured for the presence of leptospirae. Attempts were made to culture leptospirae from kidneys at slaughter. Kidneys were also examined histologically for evidence of leptospira infection. One vaccinated animal developed a respiratory disease. It was treated with antibiotics and removed from the trial. Leptosphuria was demonstrated in six of the remaining 19 vaccinated pigs and leptospirae were found in nine of 578 (1.5%) urine samples examined from these animals during the period of exposure. In contrast leptospiruria occurred in 19 of 20 unvaccinated pigs and leptospirae were found in 253 of 642 (39.4%) urine samples examined from these animals. Histopathological lesions consistent with leptospirosis were found in kidneys examined from two of 16 vaccinates and 17 of 18 non-vaccinates. Antibodies to serovar pomona were detected in 12 of 19 vaccinated pigs examined three weeks after the second dose of vaccine and before exposure to infection, and in all of 18 unvaccinated pigs examined after exposure to infection. It was concluded that use of this vaccine in pigs resulted in a significant degree of protection against leptospiruria. 相似文献
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Medicinal plants have been investigated for their anthelmintic properties and shown to be effective against eggs and larvae of gastrointestinal nematodes. The aim of this study was to evaluate the efficacy of the Lippia sidoides essential oil (LsEO) on sheep gastrointestinal nematodes. Initially, 44 naturally infected sheep were divided and treated with 200 μg kg−1 ivermectin and 230 and 283 mg kg−1 LsEO, respectively, plus the control. Fecal samples were collected from each animal to determine epg at 7, 14 and 21 days after treatment. In another test, 21 sheep were distributed and treated with 200 μg kg−1 ivermectin, 283 mg kg−1 LsEO and the control, respectively. Seven days after treatment, they were euthanized and necropsied to count and identify the nematodes from the abomasum, small and large intestines. In the first test, the efficacy of 230 and 283 mg kg−1 LsEO and ivermectin was 38%, 45.9% and 40.2%, respectively, 7 days after treatment, and 30%, 54% and 39.6%, respectively, 14 days after treatment. In the second experiment, the respective efficacy of 283 mg kg−1 LsEO and ivermectin was 56.9% and 34.4% against Haemonchus spp., and 39.3% and 63.6% against Trichostrongylus spp. 相似文献
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