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牛对铜中毒的抵抗力比羊大。然而,两群牛中,一群成年荷兰母牛和另一群杂交阉牛由于每天饲喂9—16kg的嫩稻草而引起铜中毒。患牛表现虚弱无力,沉郁和食欲减少,同时粘膜黄染,排出暗红褐色尿液;个别患牛死亡。检查其两头死牛肝脏,每公斤鲜肝中铜含量达436mg和730mg,而正常时铜的含量为30—140mg/kg。嫩稻草中铜的 相似文献
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正自从1996年暴发以来,猪繁殖与呼吸综合症病毒(猪蓝耳病病毒,PRRSv)感染的临床表现越来越复杂多样,而且现在的感染主要以多种病原混合感染为主,这使得我们难以通过剖检和肉眼病变做出准确的判断,因此,对于猪蓝耳病病毒(PRRSv)的诊断必须通过实验室的分子生物学等检测手段来进行核实。随着技术的发展,猪蓝耳病病毒(PRRSv)的实验室诊断技术有了更多的 相似文献
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Sibila M Nofrarías M López-Soria S Segalés J Valero O Espinal A Calsamiglia M 《Veterinary microbiology》2007,122(1-2):97-107
A field trial was conducted to study Mycoplasma hyopneumoniae (Mh) infection dynamics by nested polymerase chain reaction (nPCR) and serology in pigs of a farm affected by enzootic pneumonia (EP). Moreover, correlation of Mh detection at different respiratory tract sites with presence of EP gross and microscopic lung lesions was assessed. These parameters were studied and compared between vaccinated (two doses at 1 and 3 weeks of age versus one dose at 6 weeks of age) and non-vaccinated pigs. Animals were monitored from birth to slaughter by nPCR from nasal swabs and by serology. From 3 to 22 weeks of age, an average of three pigs per treatment and per batch were necropsied (n = 302). The remaining pigs were sent to the slaughter (n = 103). Nasal, bronchial and tonsillar swabs were taken from the necropsied/slaughtered pigs; gross and microscopic EP-suggestive lung lesions were also assessed. Single and double vaccination resulted in earlier seroconversion and higher percentage of Mh seropositive pigs compared to control group. At slaughter, double vaccinated pigs showed lower percentage of EP-compatible gross lung lesions and lower Mh prevalence at upper respiratory tract sites (nasal cavity and tonsil) than control pigs. 相似文献
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Jiménez A Sánchez J Andrés S Alonso JM Gómez L López F Rey J 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(2):103-106
This study looked at measurement of endotoxaemia as a tool in determining prognosis and probable response to treatment in scouring lambs. One hundred eighty-three lambs in the first 15-20 days of life, from eight Merino sheep farms located in the region of La Serena, south-west Spain, were used in this experiment. Scouring and normal/control lambs were selected following a clinical examination, the scouring group was further divided into subgroups, specifically those that did or did not survive 72 h following treatment. At the time of the clinical examination, faecal and blood samples were taken. Faecal culture and commercial faecal antigen tests for detection of enteropathogens in faeces and serum endotoxin measurement using chromogenic lymulus amoebocyte lysate (LAL) were carried out. Scouring lambs received 0.07 mg/kg liveweight halofuginone once a day for 3 days, a single oral dose of 0.20 mg/kg liveweight of spectinomycin and oral rehydration fluid. The pathogens isolated were Cryptosporidium spp. and Escherichia coli. The case fatality rate was 51% in the scouring lambs. Postmortem findings were consistent with enterotoxigenic E. coli infection. The concentration of endotoxin was 0.18 +/- 0.12 ng/ml in the control group, 0.35 +/- 0.17 ng/ml in the surviving lambs and 0.46 +/- 0.14 ng/ml in the non-surviving lambs. Significant differences between groups were found. Case fatality rate of the scouring lambs with endotoxaemia below 0.30 ng/ml was 0%, while it was 100% above 0.50 ng/ml. These results may be utilized as a prognostic indicator in lambs affected by E. coli and Cryptosporidium that will help aid in decision-making as to whether to treat a lamb or not based on its chances of survival. 相似文献
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Piles M García-Tomás M Rafel O Ramon J Ibañez-Escriche N Varona L 《Journal of animal science》2007,85(11):2846-2853
A Bayesian procedure, which allows consideration of the individual variation in the feed resource allocation pattern, is described and implemented in 2 sire lines of rabbit (Caldes and R). The procedure is based on a hierarchical Bayesian scheme, where the first stage of the model consists of a multiple regression model of feed intake on metabolic BW and BW gain. In a second stage, an animal model was assumed including batch, parity order, litter size, and common environmental litter effects. Animals were reared during the fattening period (from weaning at 32 d of age to 60 d of age) in individual cages on an experimental farm, and were fed ad libitum with a commercial diet. Body weight (g) and cumulative feed intake (g) were recorded weekly. Individual BW gain (g) and average BW (ABW, g) were calculated from these data for each 7-d period. Metabolic BW (g(0.75)) was estimated as ABW(0.75). The number of animals actually measured was 444 and 445 in the Caldes and R lines, respectively. Marginal posterior distributions of the genetic parameters were obtained by Gibbs sampling. Posterior means (posterior SD) for heritabilities for partial coefficients of regression of feed intake on metabolic BW and feed intake on BW gain were estimated to be 0.35 (0.17) and 0.40 (0.17), respectively, in the Caldes line and 0.26 (0.19) and 0.27 (0.14), respectively, in line R. The estimated posterior means (posterior SD) for the proportion of the phenotypic variance due to common litter environmental effects of the same coefficients of regression were respectively, 0.39 (0.14) and 0.28 (0.13) in the Caldes line and 0.44 (0.22) and 0.49 (0.14) in line R. These results suggest that efficiency of use of feed resources could be improved by including these coefficients in an index of selection. 相似文献
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滨江临海的江苏省通州市虽有得天独厚的水资源条件,但出存在着时段性,水质性的缺水危机,农村饮水形势不容乐观,全市农村过半数的人口处于饮水不安全状态,目前存在着苦咸水危害,农村供水水源保证不可靠,水质污染严重,基础设施简陋陈旧等突出问题,其症结在于水资源保护观念淡薄,农村供水投入不足.针对存在问题,从加强领导,区域供水,增加投入,综合治理和强化管理等5个方面提出保障通州饮水安全的对策与措施. 相似文献
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