霉菌毒素对猪免疫系统的影响

霉菌毒素是由生长在动物饲料和人类食品上的真菌所产生的结构各异的二级代谢产物。动物摄人中等至高剂量霉菌毒素引起的临床中毒综合征已有详细描述。就猪的健康而言,霉菌毒素中毒症将最终降低猪对传染性疾病的抵抗力,导致慢性感染或降低疫苗接种和药物治疗的效果。     

霉菌毒素与免疫系统

某些霉菌毒素对肉鸡免疫系统的影响要比预想的更为严重。密苏里大学的一个研究小组通过在小鸡的饲料中添加不同水平的黄曲霉毒素 B1对此进行了研究。试验结果表明 ,在添加剂量为 2 0 0 μg/kg时 ,注射 E.Coli以及在饲料中添加黄曲霉毒素 B1组肝脏和脾脏中的细菌数比只注射 E.Coli组多。试验鸡在连续饲喂含黄曲霉毒素的饲料 4周后对新城疫灭活疫苗的应答较弱。和未添加组相比 ,添加组免疫细胞对毒素的应答较慢。小剂量添加时 ,没有发现免疫系统明显的损伤 ,由此表明 ,大剂量接触黄曲霉毒素可能会引起免疫系统明显的损伤霉菌毒素与免疫系统…     

霉菌毒素可损害家禽的免疫系统

饲料质量会严重影响鸡的健康。被霉菌毒素污染的饲料可能会对鸡群的生产性能产生不良的作用,并且很可能会威胁家禽的免疫力。防止饲料受到霉菌毒素的污染仍然是最好的补救方法,但是如果霉菌毒素已经存在于饲料中,添加多价螯合剂是减小毒素不良作用的最佳措施。     

霉菌毒素对猪免疫系统的危害及解决方案

据统计,全世界每年由于霉菌污染粮食和饲料所造成的经济损失可达数千亿美元。在我国,饲料中的霉菌毒素非常普遍,而且大部分饲料原料检出的霉菌毒素都在二种以上。     

霉菌毒素的终极武器——免疫系统

解决鸡群受霉菌毒素危害的最好途径之一就是防止其对饲料的污染,但这几乎是不可能的。尽管霉菌毒素的危害可能无法完全消除,但是通过使用霉菌毒素吸附剂可将其危害降到最低。     

霉菌毒素对动物免疫系统的影响与霉菌毒素吸附剂的使用效果

美国霉菌毒素委员会的研究成果显示,霉菌毒素的核心危害作用是对免疫系统的破坏及对免疫应答的强烈抑制,从而将动物置于被感染的环境之中,导致对疾病的易感性增强,抗病力下降,这是目前中国养猪生产普遍存在而被忽略的问题。     

猪霉菌毒素中毒的临床表现

简述了生产中常见的猪霉菌毒素中毒的10种临床表现,应引起养猪场户的高度重视,以便及早发现,防范于未然。     

霉菌毒素对猪的危害及其防制

世界上每年大约有25％的谷物受到各种霉菌的污染．尤其是2003年秋收季节我省普遍阴雨连绵，气温反常，致使玉米在收获前后感染了霉菌，产生了霉菌毒素(主要有黄曲霉毒素、玉米赤霉烯酮、赭曲霉毒素、新月霉毒素群、麦角毒素、念珠镰孢霉和增生镰孢霉等)。猪采食带有霉菌毒素的玉米后，     

规模猪场的防疫体系建设

建立健全规模猪场防疫体系,科学合理地规划布局,严格实施标准化的管理和统一有效的防控措施,是阻断疫病传播途径、防止疫病发生、保障生猪安全生产的重要措施。     

饲料中霉菌毒素对家禽免疫机能的危害

霉菌毒素是由真菌(霉菌)产生的一系列化学性质各异的化合物,是家禽饲料中常见的污染物.对家禽生产造成经济损失的霉菌毒素有:黄曲霉毒素,赭曲霉毒素,单端孢菌毒素,玉米赤霉烯酮和烟曲霉毒素.霉菌毒素的有害影响主要通过四个机制:①降低采食量;②减少营养吸收;③内分泌影响以及;④抑制免疫机能.     

完善猪场防疫体系建设确保动物健康无疫

目前畜牧业正处于由数量型向质量型转变的重要时期,提高畜牧业的规模化经营、标准化生产,全面提升畜牧业产业化经营水平和畜禽     

明前“千岛玉叶” 生猪期货——养猪业的新动力

茶,久饮,可以益思、可以养性;茶馆,常往,可品茶论道,道尽天下时事……本刊市场版自2006年第4期开始,将新增设一固定栏目“博亚和讯·茶馆”。该栏目由本刊和北京博亚和讯农牧技术有限公司联合主办,旨在通过“以茶会友”为业内人士提供一个“品茶论道”、解析、交流业界热点问题的平台。市场就如此茶,需时刻关注、不断评析,久之,便可把脉市场风云,运筹帷幄。“博亚和讯·茶馆”诚挚的欢迎您来做客,品茶论道,道尽天下时事……     

The Endometrium of the Anoestrous Female Pig: Studies on Infiltration by Cells of the Immune System

The aim of this study was to investigate the distribution of immune cells in the endometrium of anoestrous female pigs, five sows in anoestrus by lactation and five pre-pubertal gilts (Swedish Landrace x Swedish Yorkshire). Uterine samples, taken immediately after slaughter, were fixed, embedded in plastic resin and stained with toluidine blue or cryo fixed and stored in a freezer at -70 degrees C until analysed by immunohistochemistry with an avidin-biotin peroxidase method. Immune cells in the surface (luminal) and the glandular epithelium as well as the subepithelial and the glandular connective tissue layers were counted using light microscopy. In the surface (luminal) and the glandular epithelia of gilts and sows, lymphocytes were the predominant immune cells found. There were no significant differences between gilts and sows. Macrophages were detected in the glandular epithelium of sows but not in gilts. In the subepithelial and the glandular connective tissue layers of both gilts and sows, lymphocytes were also the most common immune cells found. The numbers of lymphocytes and macrophages were significantly higher in the sows than in the gilts (p 相似文献   

Immune Complex‐based Vaccine for Pig Protection against Parvovirus

The insoluble immune complexes (ICs) were prepared under the conditions of double immunodiffusion in gel, using the suspension of the ultrasound treated PK‐15 cell‐line infected with porcine parvovirus (PPV) containing both viral particles and viral proteins, as well as pig or rabbit anti‐PPV polyclonal immune sera. The immunodiffusion performed in an agarose gel allows only viral subunits with a molecular mass equal to or less than 1000 kDa, rather than the viral particles, to diffuse through the gel and reach the point where the immunoprecipitate is to be formed. The immunoprecipitation under the conditions of the diffusion ensures the optimal, i.e. equimolar ratio of both immunoprecipitating components, antibody/antigen in the IC. The sodium dodecyl sulfate–polyacrylamide gel electrophoresis and the Western blot analyses showed the ICs were composed of two proteins, a protein in which molecular mass corresponded to the VP2 of the PPV and a protein with a molecular mass of the IgG. This suggests that the ICs are mainly composed of the VP2 antigen and IgG class antibodies. The potency of the IC‐vaccines prepared in the form of a water‐in‐oil‐in‐water emulsion was compared with that of a commercially available, inactivated oil vaccine. The vaccination of gilts, 6 weeks before mating, with the IC containing allogeneic pig antibodies, resulted in the development of high and long‐lasting anti‐PPV antibody titres, similar to those generated by the licenced vaccine (P > 0.01). The content of the virus material administered by the IC was twice lower than that in the licenced vaccine. Neither systemic nor local reactions were observed in the gilts during the period of the trial with the IC vaccine. The number of viable piglets per litter varied between 9 and 12 and no signs of the PPV infection were detected. Rabbits were used as one of the alternative laboratory animal models accepted for the testing of the vaccine against the PPV. The rabbit humoral immune response generated by the IC containing the allogeneic antibodies were higher than that generated by the ICs containing the xenogeneic pig antibodies. It was similar to that generated by two‐times higher content of the virus material administered by a commercially available vaccine. The IC‐based vaccines belong to non‐replicating, subunit vaccines, which are both ecologically convenient and the safest vaccines of all.     

规模猪场主要疫病的免疫技术研究

免疫是预防疫病发生的有效途径之一，本试验通过对猪瘟、口蹄疫、猪繁殖与呼吸综合征三种疫苗的免疫技术和方法进行研究。结果表明，在嘉兴某规模猪场将三种疫苗预防注射由6个时间段减少到2个时间段进行实施，既省时又省力，可减少应激，且相互间不产生干扰，新生仔猪和断乳仔猪死亡率分别从2000年的17．27％、18．71％T降到2004年的0％和0．89％，有效控制了上述疫病对生猪生产的危害。