C肉毒杀鼠素在高寒草甸地区灭鼠技术的应用

综述C肉毒杀鼠素草原灭鼠应用技术,充分肯定了C肉毒杀鼠素毒力强、适口性好、对非靶动物毒性低、作用缓慢、无二次中毒、易降解和适合规模灭鼠的特点,为鼠害防治提供了新的思路.     

C肉毒杀鼠素在高寒草甸地区灭鼠技术中的应用

综述C肉毒杀鼠素草原灭鼠应用技术,充分肯定了C肉毒杀鼠素毒力强、适口性好、对非靶动物毒性低、作用缓慢、无二次中毒、易降解和适合规模灭鼠的特点,为鼠害防治提供了新的思路。     

肃南县高原鼢鼠灭治试验

采用不同投药方式、不同浓度的C型肉毒杀鼠素、D型肉毒灭鼠剂和鼢灵杀鼠剂进行灭治高原鼢鼠的试验,结果表明:投饵方式不同,大面积灭鼠灭效差异较大;0.05%浓度组的C型肉毒杀鼠素平均灭效为89.5%,D型肉毒灭鼠剂平均灭效为86.2%;0.10%浓度组的C型肉毒杀鼠素平均灭效为85.0%,D型肉毒灭鼠剂平均灭效为89.4%;0.15%浓度组的C型肉毒杀鼠素平均灭效为90.3%,D型肉毒灭鼠剂平均灭效为94.7%;鼢灵的平均灭效为97.5%。从对环境的影响以及对人畜的安全性等方面考虑,认为采用生物灭鼠剂进行草原灭治高原鼢鼠效果更理想。     

C－型肉毒杀鼠素灭鼠试验报告

Ｃ－型肉毒杀鼠素灭鼠试验报告闫文平①胡振江②吕建国②刘中德②马应军②陈维会②刘军②孙福忱②戚长秋①（执笔）Ｃ－型肉毒杀鼠素是青海省兽医生物药品制造厂生产出的新型广谱型灭鼠药。该药品具有高效灭鼠，无二次中毒，无三致作用（致畸、致癌、致突变），对人畜无害...     

家畜C·肉毒杀鼠素中毒

C·肉毒杀鼠素是用C型肉毒梭菌的外毒素制成的高效、安全的杀鼠生物药品,近年来广泛用于草原灭鼠中。在使用过程中,若使用管理不当,投毒过量或投毒后未采取禁牧措施,可造成家畜误食而中毒。本文报道的是1992年1月在达日县特合上乡灭鼠点发生的一起家畜C·肉毒杀鼠素中毒。 (一)发病概况:该地区在1月17日完成灭鼠后,家畜到投毒区草地放牧,1月24日晚本站接到急诊报告,当即连夜赶往现场诊治。中毒家畜127头(只、匹),已死亡牲畜105头(只、匹),其中绵羊78只,马     

不同存放条件下C·肉毒杀鼠素饵粒防治高原鼠兔效果研究

将C·肉毒杀鼠素铒粒在不同存放条件下进行高原鼠兔灭治试验,结果表明,配制后的C·肉毒杀鼠素饵粒在-16℃冷库内放置47 d的0.1%和0.2%两种浓度的饵粒防效分别为94.67%和95.63%;配制后的C·肉毒杀鼠素饵粒在1～9℃仓库内放置13 d的0.1%与0.2%两种浓度的饵粒防效分别为89.10%和90.88%.在0.05水平上,A、B处理间无显著差异,C、D处理间也无显著差异.但A、B与C、D处理间存在显著差异,表明在1～9℃仓库内放置13 d的C·肉毒杀鼠素饵粒其毒力可能有所下降.     

不同存放条件下C·肉毒杀鼠素饵粒防治高原鼠兔效果研究

将C·肉毒杀鼠素铒粒在不同存放条件下进行高原鼠兔灭治试验，结果表明，配制后的C·肉毒杀鼠素饵粒在-16℃冷库内放置47d的Q1％和n2％两种浓度的饵粒防效分别为94．67％和95.63％；配制后的C·肉毒杀鼠素饵粒在1-9℃仓库内放置13d的0.1％与0.2％两种浓度的饵粒防效分别为89．10％和90．88％。在0.05水平上，A、B处理间无显著差异，C、D处理间也无显著差异，但A、B与C、D处理间存在显著差异，表明在1-9℃仓库内放置13d的C·肉毒杀鼠素饵粒其毒力可能有所下降。     

应用C型肉毒杀鼠素大面积灭鼠初探

位于内蒙古自治区西南部的伊克昭盟属典型的干旱草原区，境内干旱风沙多，植被稀疏，草原鼠害频发，以长爪沙鼠为主的地上害鼠每年的成灾面积达66．7hm^2左右，从1996年－1998年在伊克昭盟草原上开展了C型肉毒杀鼠素大面积灭鼠试验，本文中，就这一试验做统计分析后表明，该杀鼠剂灭鼠效果显著，毒饵稳定性适中，属于一种高效低毒无残留生物灭鼠制剂，同时作用时间适中无2次中毒现象。     

两种生物肉毒杀鼠素诱鼠颗粒毒饵防治高原鼠兔田间小区试验报告

通过应用C.肉毒杀鼠素诱鼠颗粒毒饵和D.肉毒杀鼠素诱鼠颗粒毒饵进行防治高原鼠兔的田间小区对比试验,结果表明:两种诱鼠颗粒毒饵防治高原鼠兔的平均校正防治效果分别可达93.65%和91.56%,两药剂间防治效果差异不显著(F=1.6990.05)。且与常用药剂(0.1%C.肉毒杀鼠素燕麦毒饵)具有相同的防治效果。     

C-型肉毒杀鼠素在草地灭鼠中应注意的事项

C-型肉毒杀鼠素是一种高效，低毒，无二次中毒，无环境污染的新型生物毒杀鼠剂，在阿勒泰地区首次应用于草原灭鼠。为确保草地大面积人工灭鼠中的人畜安全，2003年4月9日-4月15日。阿勒泰地区福海县养鸡场，对灭鼠非靶动物鸡和山羊进行了染毒试验。由于春季是牛羊等家畜体弱期，通过试验说明在放牧草场投放C-型肉毒杀鼠毒饵料。羊只误食后，四肢无力，难以在野外自然放牧条件下长途迁徙。需引起注意，设置禁牧区和禁牧期，禁牧时间15-20d。     

植物毒素免疫研究现状

植物毒素学和免疫学结合,以研究动物中毒性疾病的发生机理、诊断和防治,是一个全新的交叉性研究领域。就植物毒素免疫的免疫学基础、植物毒素人工抗原的研究和植物毒素免疫的临床研究及应用进行了综述。     

艰难梭菌毒素致病机理的研究进展

艰难梭菌是一种革兰氏阳性厌氧芽胞梭菌,是人类肠道感染的主要致病菌,其主要致病因素为毒素A(肠毒素)和毒素B(细胞毒素).毒素A引发细胞损伤后,毒素B即可侵入肠黏膜,引起细胞病变,导致一系列与感染相关的临床表现.同时,艰难梭菌毒素也是引起猪、鸡等畜禽发生腹泻的重要因素,因此探讨艰难梭菌毒素对机体的损伤作用,有利于揭示艰难梭菌的致病机理,为其防控提供理论依据.     

The fungal T-2 toxin alters the activation of primary macrophages induced by TLR-agonists resulting in a decrease of the inflammatory response in the pig

T-2 toxin is known to be one of the most toxic trichothecene mycotoxins. Exposure to T-2 toxin induces many hematologic and immunotoxic disorders and is involved in immuno-modulation of the innate immune response. The objective of this work was to evaluate the effects of T-2 toxin on the activation of macrophages by different agonists of Toll-like receptors (TLR) using an in vitro model of primary porcine alveolar macrophages (PAM). Cytotoxic effects of T-2 toxin on PAM were first evaluated. An IC₅₀ of 19.47 ± 0.9753 nM was determined for the cytotoxicity of T-2 toxin. A working concentration of 3 nM of T-2 toxin was chosen to test the effect of T-2 toxin on TLR activation; this dose was not cytotoxic and did not induce apoptosis as demonstrated by Annexin/PI staining. A pre-exposure of macrophages to 3 nM of T-2 toxin decreased the production of inflammatory mediators (IL-1 beta, TNF-alpha, nitric oxide) in response to LPS and FSL1, TLR4 and TLR2/6 agonists respectively. The decrease of the pro-inflammatory response is associated with a decrease of TLR mRNA expression. By contrast, the activation of TLR7 by ssRNA was not modulated by T-2 toxin pre-treatment. In conclusion, our results suggest that ingestion of low concentrations of T-2 toxin affects the TLR activation by decreasing pattern recognition of pathogens and thus interferes with initiation of inflammatory immune response against bacteria and viruses. Consequently, mycotoxins could increase the susceptibility of humans and animals to infectious diseases.     

Fluid accumulation in the ligated intestinal loop and histopathological changes of the intestinal mucosa caused by Clostridium botulinum C2 toxin in the pheasant and chicken

Fluid accumulation was induced in ligated intestinal loops of both pheasants and chickens injected with crude Clostridium botulinum C2 toxin. Necrosis of the epithelium and lamina propria of the duodenum and jejunum occurred in both species of bird after intraduodenal administration of crude C2 toxin. The severity of such reactions depended upon the dose and the period after administration of C2 toxin up to eight hours, and such reactions were suppressed specifically with rabbit anti-C2 toxin. These results confirm that C2 toxin is one of the causes of diarrhoea in avian botulism.     

Atypical Pasteurella strains producing a toxin similar to the dermonecrotic toxin of Pasteurella multocida subspecies multocida

This paper is the first report of the production of a dermonecrotic toxin by pasteurella strains that do not belong to the species Pasteurella multocida subspecies multocida. Four strains, isolated from cattle with atrophic rhinitis, were characterised phenotypically. The strains were related to pasteurellaceae, but their taxonomic position remained unclear. The strains produced a toxin that caused a haemorrhagic dermonecrosis in guinea pigs and was lethal to mice. Both effects were neutralised by an antiserum against the purified dermonecrotic toxin of P multocida subspecies multocida. Western blot analysis of culture filtrates of the bovine strains revealed a protein, with the same molecular weight as dermonecrotic toxin, which reacted with both polyclonal and monoclonal antibodies against the toxin. In an immunodiffusion test, anti-dermonecrotic toxin serum did not discriminate between the toxin of the bovine strains and the toxin of P multocida subspecies multocida. It is concluded that these atypical pasteurella strains produce a toxin that is closely related to the dermonecrotic toxin of P multocida subspecies multocida.     

Clostridium perfringens epsilon toxin inhibits the gastrointestinal transit in mice

Epsilon toxin produced by Clostridium perfringens type B and D is a potent toxin that is responsible for a highly fatal enterotoxemia in sheep and goats. In vitro, epsilon toxin produces contraction of the rat ileum as the result of an indirect action, presumably mediated through the autonomic nervous system. To examine the impact of epsilon toxin in the intestinal transit, gastric emptying (GE) and gastrointestinal transit (GIT) were evaluated after intravenous and oral administration of epsilon toxin in mice. Orally administered epsilon toxin produced a delay on the GIT. Inhibition of the small intestinal transit was observed as early as 1 h after the toxin was administered orally but the effects were not observed after 1 week. Epsilon toxin also produced an inhibition in GE and a delay on the GIT when relatively high toxin concentrations were given intravenously. These results indicate that epsilon toxin administered orally or intravenously to mice transitorily inhibits the GIT. The delay in the GIT induced by epsilon toxin could be relevant in the pathogenesis of C. perfringens type B and D enterotoxemia.     

饲料酵母在畜禽饲养上的运用及作用机理的探讨

本文通过饲料酵母在畜禽上运用的实例,论述了饲料酵母对畜禽的营养作用－－较高的粗蛋白及氨基酸含理、丰富的维生素及多种消化酶类,重点探讨了饲料酵母对畜禽的保健作用;酵母可改善动物胃肠道的微生态环境,促进动物体的免疫机能,还可直接与某些肠道病原微生物结合。中和毒素。     

A型产气荚膜梭菌重组菌株BL21（DE3）

采用限制性核酸内切酶酶切鉴定含α毒素突变基因的重组质粒,同时用SDS-PAGE检测不同条件下α毒素突变基因的表达情况。经酶切鉴定证实重组质粒pXMCPA02含有α毒素突变基因且基因序列和阅读框架正确。同时以IPTG为诱导剂诱导α毒素突变基因表达并对其表达条件进行优化。优化表达的结果是：培养基pH7.5,培养温度37℃,IPTG浓度0.8 mmol/L,菌体生长密度OD600达到0.8时加入IPTG,诱导时间5 h,此时重组菌株pXMCPA02蛋白表达量为35%。从而实现了α毒素突变基因的高效表达,为A型产气荚膜梭菌α毒素基因工程菌苗的生产工艺研究提供了可靠的试验数据。     

山东疫区魏氏梭菌血清型的多重PCR检测

采用多重PCR对从流行过魏氏梭菌病的牧场粪便样品中分离魏氏梭菌的α、β、ε、ι 毒素基因进行了检测,确定了血清型。电泳成像显示,仅魏氏梭菌扩增出了特异性条带,其他对 照菌株无,说明该方法具有很高的特异性。通过对山东德州、枣庄、泰安、临沂、青岛等地养殖场 的418个样品分离的62个菌株的检测,检出率为14．8％,均为A型。研究确认,多重PCR是 魏氏梭菌血清型鉴别的一种快速、简便的研究方法,山东省流行型别与国外报道不完全一致。