Frank R, Braun H E, Wilkie I, Ewing R
Can Vet J. 1991 Apr;32(4):219-26.
From 1982 to 1989, inclusive, 20 poisonings were investigated by the Ontario Ministry of Agriculture and Food following ingestion by domestic livestock of granular insecticides including terbufos (13 poisonings), disulfoton (two poisonings), fonofos (two poisonings), phorate (two poisonings), and carbofuran (one poisoning); all are used for rootworm (Diabrotica spp.) control in corn. A further three poisonings of livestock occurred following the ingestion of the foliar insecticide, endosulfan (two poisonings), and the seed protectant insecticides diazinon plus lindane (one poisoning). There were six poisoning cases as a result of excessive topical applications of the three insecticides coumpahos, fenthion, and lindane as dusts or sprays to control external parasites. Together, these events caused the deaths of 258 domestic animals of which 200 were cattle, 23 were swine, and 35 were sheep. Not all deaths are reported to the Ministry and the cases reported here may only represent 30-50% of the actual deaths over the period. Based on total populations of livestock, the percent losses were very small but they represent serious losses to individual growers. The economic loss is estimated at $160,000 over the eight years, or $20,000 per annum, and this does not include veterinary costs.Some of the poisoned animals died within as little as three to four hours of ingestion while others were sick but survived for several days. Lethal doses of insecticide were found in the rumen, abomasum, or stomach of dead animals. Signs typical of cholinesterase inhibition caused by organophosphorus poisoning were observed in most cases. Cholinesterase readings were found to be zero in dying animals. Necropsy findings were rarely more than pulmonary edema or myocardial hemorrhage. Where organochlorine insecticides were ingested, convulsions were the major manifestation.Contamination of feed was most often accidental, and chemical analysis was most helpful in identifying both potent and minor sources, thus facilitating cleanup procedures.
1982年至1989年（含1982年和1989年）期间，安大略省农业和食品部对20起中毒事件展开调查，这些事件是由于家畜摄入颗粒状杀虫剂所致，其中包括特丁磷（13起中毒事件）、乙拌磷（2起中毒事件）、地虫硫磷（2起中毒事件）、甲拌磷（2起中毒事件）和呋喃丹（1起中毒事件）；所有这些杀虫剂均用于防治玉米中的根虫（玉米根萤叶甲属）。另外还有3起家畜中毒事件，是由于摄入了叶面杀虫剂硫丹（2起中毒事件）以及种子保护剂杀虫剂二嗪农加林丹（1起中毒事件）。因过量局部使用三种杀虫剂——蝇毒磷、倍硫磷和林丹作为粉剂或喷雾剂来防治体外寄生虫，导致了6起中毒事件。这些事件共导致258头家畜死亡，其中200头是牛，23头是猪，35头是羊。并非所有死亡事件都上报给了该部，此处报告的案例可能仅占该时期实际死亡数的30%至50%。基于家畜的总数量，损失百分比非常小，但对个体养殖户来说却是严重损失。据估计，这八年间的经济损失为16万美元，即每年2万美元，且这还不包括兽医费用。一些中毒动物在摄入杀虫剂后短短三到四个小时内就死亡了，而其他动物虽生病但存活了几天。在死亡动物的瘤胃、皱胃或胃中发现了致死剂量的杀虫剂。在大多数案例中，观察到了有机磷中毒引起的典型胆碱酯酶抑制症状。在濒死动物中，胆碱酯酶读数被发现为零。尸检结果通常仅为肺水肿或心肌出血。当摄入有机氯杀虫剂时，抽搐是主要表现。饲料污染大多是意外造成的，化学分析对于识别主要和次要污染源最为有用，从而便于清理程序。
