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101.
102.
During the summer of 1990 deaths, occurred in racing camels (Camelus dromedarius) associated with a specific disease syndrome. Clinical signs included pyrexia, coughing, lachrymation, oedema of the throat and submandibular region and enlargement of submandibular lymph nodes. In terminal cases nervous signs were present and sometimes there was bloody diarrhoea and vomiting. Of 480 camels at least 70 animals were affected with the disease and about 40 died. Morbidity and mortality was greater in camels recently imported. Consistent necropsy findings were extensive petechial and ecchymotic haemorrhage beneath the epicardium, endocardium and visceral pleura and in the mediastinal lymph nodes, and haemorrhagic oedema of the pharyngeal and laryngeal areas. Haemorrhages occurred more variably in abdominal organs and on the omasal and abomasal mucosa. Bronchopneumonia, omasitis and abomasitis were observed on microscopic examination, together with liver and kidney lesions of presumed toxic origin. Fungal hyphae and, occasionally, the characteristic conidial morphology of Aspergillus fumigatus were seen in sections and direct smears from lesions in the respiratory and alimentary tracts. A fumigatus was cultured from trachea, bronchi, bronchioles, lung tissue, heart blood, omasum, abomasum, ileum and submandibular lymph nodes. Whether the role of Aspergillus in the overall syndrome is primary or secondary has not been established; no other potential aetiological agent has been identified.  相似文献   
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OBJECTIVE: To evaluate organoleptic postmortem inspection techniques for bovine livers and kidneys. STUDY DESIGN: At Australian export abattoirs, bovine liver and kidneys are assessed and graded by qualified meat inspectors during normal operations. Over a 12-month period at a large abattoir in eastern Australia during 1997 and 1998, a sample of these organs was reassessed independently using a range of pathological and microbiological methods. Agreement between routine inspection and independent assessment was evaluated using methods of inter-rater agreement. RESULTS: A total of 944 livers and 1374 kidneys were included in the study. All of these organs had been classified during routine inspection. The authors examined 363 livers and 329 kidneys both grossly and histologically, including 36 livers and 14 kidneys that were also subjected to microbiological examination. All other organs were only examined grossly. There was only a moderate level of agreement between the routine and independent assessment methods. For livers, the percentage agreement was 80.2%, McNemar's test of symmetry 55.2 (3 degrees of freedom, P < 0.001) and kappa 0.63. For kidneys, the percentage agreement was 67.8%, McNemar's test of symmetry 9.9 (1 df, P = 0.002) and kappa 0.35. CONCLUSIONS: The results reinforce concerns from a number of authors about organoleptic postmortem inspection. Risk assessment methodologies offer the opportunity to modify inspection techniques in a manner that is most relevant to current public health concerns.  相似文献   
105.
Thirteen cows, which had been vaccinated as calves with strain 19, were revaccinated twice or three times as adults with 1×109 cfu of B. abortus strain RB51. Their serological responses following adult vaccination remained negative to conventional brucellosis surveillance tests. Vaccination with strain RB51 during the eighth month of pregnancy did not induce abortion, although strain RB51 was recovered from milk for up to 69 days after vaccination. In a parallel study, thirteen 8- to 10-month-old heifers were vaccinated as calves with 109 cfu of strain RB51. The heifers remained seronegative to conventional brucellosis surveillance tests but antibody responses to RB51 could be demonstrated using an indirect ELISA. This study showed that multiple vaccination with strain RB51 did not induce seroconversion to brucellosis surveillance tests. In addition, this study suggests that 109 cfu of strain RB51 is safe for use in pregnant cattle.  相似文献   
106.
Enterotoxaemia of sheep and goats occurs worldwide, but the condition in goats is poorly understood. The disease in goats is mostly caused by Clostridium perfringens type D, although the role of the toxins of this microorganism in the pathogenesis of the disease is not fully understood. The disease occurs in three forms, peracute, acute and chronic, the cardinal clinical sign of the acute and chronic forms being diarrhoea. The main biochemical alterations are hyperglycaemia and glycosuria, while at necropsy the disease is often characterized by haemorrhagic colitis. The typical histological changes observed in the brain of sheep with enterotoxaemia are not considered to be a common feature of enterotoxaemia in goats. Although the pathogenesis of caprine enterotoxaemia has not yet been properly defined, it is usually accepted that the presence of C. perfringens type D in the small bowel, together with a sudden change to a diet rich in carbohydrates, is the main predisposing factor for the disease. Vaccination seems to be poorly effective in preventing caprine enterotoxaemia, which might be due to the fact that the enteric form of the disease is partially independent of circulating C. perfringens toxin. More studies are needed on caprine enterotoxaemia, especially of its pathogenesis and immunity, in order to develop more efficient control measures for this disease.  相似文献   
107.
Primary amoebic meningoencephalitis is a fulminant infection of the human central nervous system caused by Naegleria fowleri, a free-living amoeba that thrives in artificially or naturally heated water. The infection usually is acquired while bathing or swimming in such waters. The portal of entry is the olfactory neuroepithelium. This report describes fatal meningoencephalitis caused by N. fowleri in Holstein cattle that consumed untreated surface water in an area of California where summer temperatures at times exceed 42 degrees C. In the summers of 1998 and 1999, severe multifocal necrosuppurative hemorrhagic meningoencephalitis was observed in brain samples from nine 10-20-month-old heifers with clinical histories of acute central nervous system disease. Olfactory lobes and cerebella were most severely affected. Lesions were also evident in periventricular and submeningeal neuropil as well as olfactory nerves. Naegleria fowleri was demonstrated by immunohistochemistry in brain and olfactory nerve lesions and was isolated from one brain. Even though cultures of drinking water did not yield N. fowleri, drinking water was the likely source of the amoeba. The disease in cattle closely resembles primary amoebic meningoencephalitis in humans. Naegleria meningoencephalitis should be included among differential diagnoses of central nervous system disease in cattle during the summer season in areas with high ambient temperatures.  相似文献   
108.
Currently, the factors/toxins responsible for Clostridium perfringens-associated avian enteritis are not well understood. To assess whether specific C. perfringens' toxinotypes are associated with avian enteritis, the isolates of C. perfringens from 31 cases of avian necrotic or ulcerative enteritis submitted between 1997 and 2005 were selected for retrospective analysis using multiplex PCR. C. perfringens was isolated from chickens, turkeys, quail, and psittacines. The toxinotypes of isolates from diseased birds were compared against the toxinotype of 19 C. perfringens isolates from avian cases with no evidence of clostridial enteritis. All C. perfringens isolates were classified as type A regardless of species or disease history. Although many isolates (from all avian groups) had the gene encoding the C. perfirngens beta2 toxin, only 54% produced the toxin in vitro when measured using Western blot analysis. Surprisingly, a large number of healthy birds (90%) carried CPB2-producing isolates, whereas over half of the cpb2-positive isolates from diseased birds failed to produce CPB2. These data from this investigation do not suggest a causal relationship between beta2 toxin and necrotic enteritis in birds.  相似文献   
109.
通过体内、体外试验探究荷叶总生物碱的降脂减肥作用.给予高脂血症大鼠模型组不同剂量荷叶总生物碱和降脂药物辛伐他汀(阳性药物对照组),观察荷叶总生物碱对高脂血症大鼠体质量、体脂以及血清脂质相关指标的影响;用对硝基苯酚法检测不同质量浓度荷叶总生物碱处理对大鼠胰脂肪酶活性的影响.结果显示:荷叶总生物碱能显著降低高脂血症大鼠的体质量,显著降低血清总胆固醇、血清甘油三酯、低密度脂蛋白胆固醇含量,显著降低谷草转氨酶、谷丙转氨酶活性以及动脉粥样系数,升高高密度脂蛋白胆固醇/血清总胆固醇比值;荷叶总生物碱能抑制脂肪酶活性,抑制类型为非竞争性抑制;在荷叶总生物碱质量浓度为12.5~600μg/mL范围内,对脂肪酶的抑制效果随其质量浓度的增加而增强,在600μg/mL时达到最大抑制率,为25.6%,当荷叶总生物碱质量浓度继续增加时,抑制率趋于平缓,保持在最大值附近.体内、体外试验结果均表明,荷叶总生物碱类物质具有降脂减肥作用,提示其可能具有预防肥胖、调节脂代谢紊乱的功效.  相似文献   
110.
An adult male Pygmy goat with a history of losing hair and declining body condition was euthanized, and a complete diagnostic work-up was performed. The animal showed diffuse alopecia on the dorsal and lateral sides of thorax and abdomen, proximal legs, neck and face. Histology revealed diffuse orthokeratotic hyperkeratosis, epidermal hyperplasia and perivascular dermatitis. Broad-based budding yeasts and hyphae were visible in the keratin layer. Malassezia slooffiae was identified in the skin by polymerase chain reaction amplification of part of the large subunit rRNA gene using broad-range fungal primers and DNA sequencing. This is the first report of M. slooffiae-associated dermatitis in goats.  相似文献   
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