Blakley B R, Clark E G, Fairley R
Can Vet J. 1990 May;31(5):385-7.
Young pigs, six to ten weeks of age, from two unrelated swine operations were fed a grower ration obtained from a common commercial supplier. Following ingestion of the feed for approximately two weeks, pigs in both groups developed neurological disturbances characterized by blindness, ataxia, incoordination, muscle tremors, posterior paralysis, and quadriplegia. Vocalization described as "screaming" was also observed in several animals. Necropsy findings and tissue arsenic concentrations were consistent with a diagnosis of phenylarsonic acid poisoning. The liver and kidney contained an average arsenic content of 2.9 and 1.8 mg/kg (wet weight), respectively. The feed contained 38 mg of arsenic/kg corresponding to 133 mg roxarsone (3-nitro-4-hydroxyphenylarsonic acid)/kg. This level of roxarsone is approximately three to five times higher than the levels recommended for swine rations. The feed company had placed roxarsone in the ration at levels recommended for the less toxic arsanilic acid. It was assumed that the two organic arsenicals could be added to the rations interchangeably at the same level of formulation. The present investigation indicated that roxarsone is more toxic than arsanilic acid and the margin of safety in swine rations is low.
从两个不相关的养猪场选取6至10周龄的幼猪，投喂从同一家商业供应商处获得的生长猪日粮。在摄入该饲料约两周后，两组猪均出现神经功能紊乱，表现为失明、共济失调、运动不协调、肌肉震颤、后肢麻痹和四肢瘫痪。在几只动物中还观察到被描述为“尖叫”的发声。尸检结果和组织砷浓度与苯胂酸中毒的诊断一致。肝脏和肾脏中的平均砷含量分别为2.9毫克/千克和1.8毫克/千克（湿重）。该饲料含砷量为38毫克/千克，相当于洛克沙胂（3-硝基-4-羟基苯胂酸）133毫克/千克。这个洛克沙胂水平比猪日粮推荐水平高出约三到五倍。饲料公司在日粮中添加洛克沙胂的水平是按照毒性较低的对氨基苯胂酸的推荐量。据推测，这两种有机胂化合物在相同配方水平下可以互换添加到日粮中。本次调查表明，洛克沙胂比氨基苯胂酸毒性更大，猪日粮中的安全边际较低。
