Tenth international congress of plant protection,Brighton, November 1983

Abstract

Field trials were conducted to control rodent pests of wheat crop by improving bait acceptability through taste enhancers (additives). Egg shell, egg yolk, yeast, minced meat, sheep blood and chicken blood were mixed 2% by weight individually in a bait base of broken rice and wheat flour. Brodifacoum and bromadiolone bait with egg shell additive ranked first, and egg yolk second, in preference over other additive poison baits and poison bait without additive. Poison baiting yielded 93.3% and 86.7% reduction in rodent population with brodifacoum and bromadiolone (0.005% each), respectively. Three baitings, at tillering, flowering and maturity stage of the crop, gave 91.0% tiller damage reduction with brodifacoum and 86.0% with bromadiolone as compared to control (untreated). It is concluded that three poison baitings containing egg shell additive should be initiated at tillering stage followed by flowering and maturity of the wheat crop for increased yield.     

增效溴敌隆对几种害鼠的毒杀作用

本文涉及一种抗凝血增效灭鼠剂的研制和应用.该灭鼠剂是以溴敌隆为主剂、以双氯芬酸钠、丙三醇等为辅剂,可制成液剂和粉剂.经生物测定表明,对大白鼠、小白鼠、褐家鼠、大仓鼠和布氏田鼠均有很好的毒效,毒杀率基本达到100％,且适口性良好.现场试验对褐家鼠防效达96％以上.该药中溴敌隆含量为0.002％时,防效与0.005％溴敌隆相当起到了增效的作用,降低了成本,减少了环境污染,保证了人畜安全.     

Resistance tests and field trials with bromadiolone for the control of Norway rats (Rattus norvegicus) on farms in Westphalia, Germany

BACKGROUND: The aim of this study was to determine the incidence and the level of resistance to bromadiolone among rats on farms suspected of being foci of resistance by using the international normalised ratio (INR)‐based blood clotting response (BCR) test. Whether the level of reduced susceptibility constitutes ‘practical resistance’ was subsequently determined in field trials. RESULTS: The 2.5 multiple of the ED₅₀ baseline was used to test for the incidence of resistance, and higher multiples in the range of the suspected resistance factor were used to investigate the degree of resistance. The ED₅₀ values of bromadiolone in resistant rats were confirmed in the range 4.70–7.05 mg kg^?1 for males and 4.62–6.61 mg kg^?1 for females. Variations within these ranges appeared between farms. According to the BCR resistance tests, 50–100% of rats were classified as resistant prior to the field trials; 29–100% of rats survived the treatments. CONCLUSION: BCR tests based on the use of the INR and baselines are suitable for determining the incidence and for assessing the level of resistance in populations of Norway rats. The majority of rats of the Westphalian resistant strain, characterised by the Y139C marker in VKOR, are resistant to bromadiolone under practical control conditions. Copyright © 2011 Society of Chemical Industry     

杀鼠剂溴敌隆与小牛胸腺DNA的相互作用

利用紫外光谱和荧光光谱研究二代抗凝杀鼠剂溴敌隆(BRD)与小牛胸腺DNA(ct-DNA)的相互作用.结果表明:ct-DNA可使BRD的紫外吸收光谱发生增色,但试验中没有观察到明显的光谱红移及等吸收点的出现;ct-DNA对BRD的稳态荧光有明显的猝灭作用,属于静态猝灭方式;通过热力学分析判断BRD与ct-DNA之间的相互作用主要是氢键和范德华力作用.吸收光谱、竞争试验、阴离子猝灭试验以及离子强度影响试验一致表明,BRD与ct-DNA之间主要以沟区结合方式发生作用.     

Reproductive success of bromadiolone-resistant rats in absence of anticoagulant pressure

Resistance to anticoagulant rodenticides in brown rats (Rattus norvegicus Berk.) is associated with pleiotropic effects, notably with an increased dietary vitamin K requirement. Owing to this disadvantage, resistance is believed to be selected against if anticoagulant selection is absent. In small experimental populations of wild brown rats, an investigation was carried out to establish whether tolerance to anticoagulant exposure changed over a period of 2 years. In the same populations, DNA microsatellite markers were used to infer parentage, and this made it possible to estimate reproductive success of sensitive and resistant rats and estimate effective population size, Ne. Even though there was evidence for a selection against resistant rats with high vitamin K requirement, anticoagulant tolerance was not seen to be significantly influenced in the absence of bromadiolone selection. As the population size under investigation was small, random genetic drift may have played a role in this. In the presence of bromadiolone selection, however, the tolerance was significantly increased, suggesting that continuous selection will increase the proportion of highly resistant rats in the population. It was found that, for both males and females, surprisingly few individuals contributed to the next generation with numerous offspring, and most breeders contributed with none or a single offspring. The expected higher reproductive success and consequent increase in proportional numbers of sensitive rats in the absence of anticoagulant selection could not be observed. Among the resistant rats, moderately resistant females were found to be better breeders than highly resistant breeders, but for resistant males the reverse was true. This could be explained by the fact that the increased vitamin K requirement results in sex differential selection; in highly resistant males the selection presumably takes place at the immature stage, whereas in females the vitamin K requirement becomes crucial at the reproductive stage, as vitamin K is not only essential for the blood clotting process but also for bone formation.     

EP-1与溴敌隆对长爪沙鼠野生种群增长的控制作用

2010年3—10月,在内蒙古鄂尔多斯荒漠草原分别设置不育剂试验区、毒饵试验区和对照区3个样区,采用春季一次性足量投饵、按月铗捕统计种群相对数量的方法,比较了不育剂EP-1和毒饵溴敌隆对长爪沙鼠Meriones unguiculatus野生种群数量增长的控制作用。结果显示,EP-1改变了 长爪沙鼠种群的年龄结构,不育剂区与毒饵区成体组成差异显著(F_{2, 14}=5.89,P<0.05),降低了长爪沙鼠幼体出生率和全年种群密度,全年幼体数量和总体种群数量均呈下降趋势(R₃²=0.8552,R₄²=0.5126)。EP-1对长爪沙鼠种群增长有持续控制作用,而溴敌隆对长爪沙鼠种群的有效杀灭作用只持续3个月,仅是短期控制。     

两种助剂对溴敌隆毒饵的增效作用研究

【目的】为提高杀鼠剂的利用率及防控效果，降低其生态风险，研究了渗透剂对抗凝血灭鼠剂溴敌隆的增效作用。【方法】采用高效液相色谱法，检测添加不同种类及不同浓度的助剂后稻谷毒饵中溴敌隆的含量分布；采用有选择摄食试验和无选择摄食试验的生物测定方法，分别测试不同方法制成的溴敌隆毒谷对小鼠的适口性及毒杀效果。【结果】经 4%N, N- 二甲基甲酰胺及 4% 二甲基亚砜处理后，0.01% 溴敌隆毒谷糙米中的药物含量均显著提高，比常规的 0.01% 溴敌隆毒谷分别增加 271.17% 和 163.51%；而添加 4%N, N- 二甲基甲酰胺和 4% 二甲基亚砜配制的 0.0025% 溴敌隆毒谷，糙米中的药物含量均显著高于常规 0.0025% 溴敌隆毒谷，分别增加 433.33% 和 400.95%；生物测定结果表明，用 4% 的两种助剂配制的 0.0025% 溴敌隆毒谷，对小白鼠均具有较好的适口性及毒杀效果，摄食系数分别为 2.69 和 0.80；毒杀率分别为 100% 和 90%，均显著高于常规的0.0025% 溴敌隆毒谷，与 0.01% 溴敌隆毒谷无显著差异。【结论】使用 4%N, N- 二甲基甲酰胺或 4% 二甲基亚砜作为助剂对溴敌隆毒饵均有显著的增效作用，并可显著降低杀鼠剂的使用浓度。     

0.02%溴敌隆(当归)毒饵防治中华鼢鼠药效试验

试验结果表明；0.02%溴敌隆毒饵（当归）对中华鼢鼠具有较好的防治效果。春季投药1次，可有效控制其危害，适宜用药量（商品量）为5g/洞。