加拿大奶牛肉牛铅中毒

1、铅中毒Lead PoisoningPrepared by: Dr. Terry Hunt Translated by Dr. Ren Xiaoling 病因/发病机理 Cause & Pathogenesis牛最常见的无机物中毒Most common inorganic poisoning in cattle牛采食不加选择吸收是重要来源Cattle are indiscriminant eaters ingestion is the major source主要来源是旧电池，机油，从矿区来的植物和水，含铅的燃料和油漆Major sources are old batteries, contam

2、inated soil, water and vegetation from mines & smelters, crankcase oil from lead base gas engines & lead based paints危险因素Risk Factors在牧场丢弃含铅的垃圾Discarded lead containing garbage in pasture areas临床症状Clinical Findings急性Acute常见于犊牛，成年牛罕见Common in calves but rare in adults突然发作，可发现死亡Sudden onset and may be

3、 found dead颤抖（头，颈，耳），步履蹒跚，牙关紧闭，口吐白沫，流涎Tremors (head, neck & ears), staggering gait, jaw champing & frothy saliva吼叫，转圈，前冲和狂躁兴奋Bellowing, circling, head pressing & maniacal excitement眼睑 ，眼球转动，瞎，光脓肿和眼睑反射Eyelid snapping, rolled eyes, dilated pupils, blind and abscess of light & palpebral reflex发展为卧地不起，间

4、歇性抽搐，12-24小时死亡Progresses to recumbency, intermittent convulsions and death in 12-24 hours亚急性Sub-acute成年牛常见More common in adults严重精神沉郁Severe depression厌食，瘤胃蠕动完全停止Anorexia & complete absence of rumen motility变瞎，缺乏光和眼睑反射Blind, absence of light & palpebral reflex步履蹒跚，转圈，前冲，牙关紧闭Staggering gait, circling,

5、 head pressing & teeth grinding初期便秘，但可能继而为黑色腹泻Initial constipation but may continue on to black diarrhea发展为卧地不起，常间歇性抽搐，3-4天内死亡Progresses to recumbency usually without convulsions and death in 3-4 days亚临床Sub-clinical牛慢性消化不良Cattle subject to chronic ingestion of lead生长缓慢Decreased rate of growth贫血Anemi

6、a诊断Diagnosis病史，临床症状，尸体剖检和全血铅水平History, clinical signs, post mortem results & whole blood levels of lead鉴别诊断Differential Diagnosis脑灰质软化病Polioencephalomalacia维生素A缺乏症Vitamin A deficiency低镁抽搐症Hypomagnesaemia Tetany神经性酮病Nervous ketosis无机物砷中毒Inorganic arsenic poisoning伪狂犬Rabies脑膜脑炎Meningoencephalitis食盐中毒S

7、alt poisoning 实验室和病理学诊断Laboratory and Pathology全血中有铅沉积(0.3 ppm)Lead concentration in whole blood (0.3 ppm)肝、肾(25 mg/kg 湿重)、网胃中铅水平Lead levels in liver, kidney (25 mg/kg wet weight) or reticulum尸体剖检-网胃中有铅碎片 Post-mortem lead fragments in reticulum组织学-水肿和脑皮质充血Histology - edema & congestion of cerebral c

8、ortex治疗Treatment治疗效果通常不好Response to treatment is often poor用安替比林和戊巴比妥以减轻急性神经症状Sedation with pentobarbital to relieve acute nervous signs从网胃和瘤胃中取出铅Rumenotomy to remove lead from reticulum and rumen静脉注射6.6%的乙二胺四乙酸钙， 0.5 ml/kg每天二次，连续用3-5天Ca EDTA (Calcium versenate) - 6.6% soln. administered IV 0.5 ml/kg twice daily for 3-5 days盐酸维生素B1每天2 mg/kgThiamine HCl 2 mg/kg daily仔细护理Good nursing care瘤胃内容物移植Rumen transplants预后情况Prognosis治疗效果不好的谨慎Guarded to poor后遗症Sequelae慢性生产性能低下Chronic poor doer乳、肉中铅蓄积Accumulation of lead in the milk & meat预防Prevention & Control适当的营养以防异食癖Adequate nutrition to help