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51.
AIM: To determine the diagnostic capability of a newly developed Western blot (WB) assay for the detection of serum antibodies against Mycoplasma agalactiae compared with conventional serological tests, and to identify the best test for routine diagnostic use. METHODS: The serological test methods used were: two commercial indirect enzyme-linked immunosorbent assays (ELISA), viz ELISA-1, using a bacterial antigen preparation, and ELISA-2, using a recombinant protein (lipoprotein p48) antigen; the complement fixation test (CFT); and a newly developed WB assay, the latter both using a bacterial antigen preparation. Thirty sera from goats infected with M. agalactiae and 97 sera from non-infected sheep were tested using all four methods. RESULTS: Staining patterns in the WB were quite variable. An immuno-dominant band of 41 kDa was detected in 63% of sera from infected animals. The same band also appeared, although mostly very weakly, in 10% of sera from non-infected animals. When suspicious or very weak reactors were omitted, the diagnostic sensitivity (DSE) and diagnostic specificity (DSP), respectively, for the four assays were: WB=56.7%, 97.9%; ELISA-1=76.7%, 99.0%; ELISA-2=56.7%, 100%; and CFT=40.0%, 94.8%. CONCLUSIONS: ELISA-1 performed best in this comparison. While the WB can be used, it did not have a technical advantage over the ELISA. The CFT should be discouraged as the primary screening method for contagious agalactia and should be replaced by ELISA-1. Results from this study confirm that serological test methods for contagious agalactia are useful for the detection of infected flocks but will not detect every individual infected animal.  相似文献   
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The present study provides the first data about the prevalence of Salmonella contamination of broilers and slaughterhouses in the region of Constantine, Algeria. The serotypes and anti-microbial resistance phenotypes of the isolates were determined, and risk factors contributing to the contamination were evaluated. A total of 2490 samples, 1800 originating from 30 broiler farms and 690 from 15 slaughterhouses, were taken during two periods: March 2005-June 2006 and September 2006-March 2007. Salmonella contamination concerned 37% of the broiler farms and 53% of the slaughterhouses. Among the 55 isolates recovered, 10 different serotypes were identified. The most frequently recovered serotypes in both slaughterhouses and breeder farms were S. Hadar (36%, n = 20), S. Virchow (16%, n = 9), S. Infantis (10.9%, n = 6), S. Albany (11%, n = 6) and S. Carnac (7%, n = 4). Isolates belonging to S. Heidelberg (2%, n = 1) and S. Rissen (2%, n = 1) were found only in farms, while those belonging to S. Typhimurium (9%, n = 5), S. Enteritidis (4%, n = 2) and S. Montevideo (2%, n = 1) were recovered only from slaughterhouses. Thirty-nine isolates (80%) were resistant to at least one anti-microbial and 51% were multi-resistant, i.e. resistant to two or more anti-microbial molecules. About 58% (n = 32) were resistant to streptomycin, 36% (n = 20) to tetracyclines, 27% (n = 15) to nalidixic acid, 13% (n = 7) to ofloxacin and one isolate to enrofloxacin. Finally, seven distinct anti-microbial resistance profiles were identified. In parallel, four risk factors were found to be significantly associated with Salmonella contamination. Together with the huge spread of Salmonella in the broiler production chain in Constantine, Algeria, these risk factors highlight the hazards of the broiler channels, particularly linked to poor technical and hygiene practices.  相似文献   
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Distance learning courses in veterinary epidemiology, taught in French and spread over half a year, were organized in 2003 and 2004. They were the subject of surveys concerning need, evaluation, attaining learning objectives, and satisfaction, the results of which will be used to improve the course scheduled to take place in 2005.  相似文献   
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Treatment of sham-operated female silver eels with carp pituitary extract stimulated ovarian development and induced increases in pituitary gonadotropin (GTH) and gonadoliberin (GnRH) contents. Both effects of carp pituitary extract were abolished in ovariectomized eels, indicating the involvement of the gonads. Endogenous sexual steroids, the secretion of which was increased during sexual maturation, should be responsible for the stimulation of GTH and GnRH levels. Ovariectomy itself had no significant effect on pituitary GTH and GnRH contents, reflecting the fact that, at the silver stage, sexual steroid levels are too low to exert any significant effect on pituitary GTH and GnRH. The positive feedback control exerted by the gonads on GTH and GnRH levels during sexual maturation, in the eel as well as in some other teleosts, would produce an amplification of the pubertal stimulation of the hypothalamo-pituitary-gonadal axis.  相似文献   
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为了解沧州市滨海盐碱区耕层土壤的盐渍化特征,采集三个时期沧州不同地区耕层土壤(0~20 cm)样品,结合样品实验分析,探究土壤盐分特征。结果表明:①沧州滨海盐碱区耕层土壤离子类型多样,检测的八大离子中氯离子、钠离子、硫酸根、碳酸根+碳酸氢根离子为主要盐分离子,土壤类型为硫酸盐-氯化物型。②相关分析表明,耕层土样中总含盐量与氯离子和钠离子均存在显著或极显著相关关系,沧州市滨海盐碱地耕层土壤的总含盐量一定程上取决于土壤中氯化钠的含量;氯化钠、氯化镁和氯化钙为氯化物的主要组成部分;主要硫酸盐类为硫酸钠、硫酸镁和硫酸钙。③方差分析表明,三个不同采样时期和不同地区均对沧州市滨海区盐碱地的盐渍化的影响存在显著或极显著差异。④主成分分析表明,钠离子、氯离子、镁离子、钙离子和硫酸根与第1主成分相关性较高;钾离子和碳酸根+碳酸氢根与第2主成分相关性较高;第3主成分主要反映硅酸盐类对土壤离子成分的影响。由于钠离子、氯离子、钙离子和硫酸根在土壤中含量相对较高,是表征沧州滨海盐碱区土壤盐渍化的主要特征因子。  相似文献   
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Abortion caused by neosporosis in cattle   总被引:2,自引:0,他引:2  
  相似文献   
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The objective of the present study was to characterize changes in serum metabolic hormones concentrations from 20 weeks before to 20 weeks post-puberty in bulls and to investigate the associations of metabolic hormones concentrations with testicular development. Leptin concentrations increased from 16 weeks before puberty to 8 weeks post-puberty and insulin concentrations increased from puberty to 8 weeks post-puberty. Growth hormone concentrations decreased after 4 weeks post-puberty, whereas IGF-I concentrations increased from 8 weeks before puberty to 8 weeks post-puberty. During this period, testicular growth was accelerated and testosterone secretion increased substantially, without any significant changes in gonadotropin secretion. Monthly circulating concentrations of leptin, IGF-I and insulin accounted for 63% of the variation in scrotal circumference and 59% of the variation in paired testes volume. In conclusion, the secretion of metabolic hormones was not associated with changes in gonadotropins concentrations. Furthermore, the associations of leptin, IGF-I and insulin concentrations with testes size indicated that these hormones might be involved in a gonadotropin-independent mechanism regulating the testicular development in peripubertal bulls.  相似文献   
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