Rasmussen M A, Allison M J, Foster J G
National Animal Disease Center, USDA-ARS, Ames, Iowa 50010.
Vet Hum Toxicol. 1993 Apr;35(2):123-7.
This paper describes the signs of toxicity when seed-bearing flatpea (Lathyrus sylvestris L) hay is fed to sheep. Signs of intoxication (including seizure, muscular trembling and spasmotic torticollis) are similar to those observed for ammonia toxicity in ruminants. Accumulation of ammonia may be a direct consequence of flatpea ingestion, given that 2,4-diaminobutyric acid (DABA, a toxic constituent of flatpea) is known to inhibit hepatic urea synthesis. However, other modes of toxicity for DABA as well as other flatpea toxins may also contribute to this process of intoxication. Our evidence suggests that ruminal microbes are responsible for flatpea detoxification and host animal protection. The adaptation of sheep to flatpea may be a consequence of enhanced ruminal detoxification activity. Ruminal protective functions can be disrupted, however, through abrupt monensin feeding or the replacement of nonadapted for adapted rumen contents. This disruption temporarily suppresses mechanisms of ruminal detoxification. As a consequence sheep can again be made vulnerable to flatpea intoxication.
本文描述了给绵羊喂食结籽香豌豆（Lathyrus sylvestris L）干草时的中毒迹象。中毒迹象（包括癫痫发作、肌肉颤抖和痉挛性斜颈）与反刍动物氨中毒时观察到的症状相似。氨的积累可能是摄入香豌豆的直接后果，因为已知2,4-二氨基丁酸（DABA，香豌豆的一种有毒成分）会抑制肝脏尿素合成。然而，DABA以及香豌豆的其他毒素的其他中毒方式也可能导致这一中毒过程。我们的证据表明瘤胃微生物负责香豌豆的解毒和宿主动物的保护。绵羊对香豌豆的适应可能是瘤胃解毒活性增强的结果。然而，通过突然喂食莫能菌素或用适应的瘤胃内容物替代未适应的瘤胃内容物，瘤胃的保护功能可能会受到干扰。这种干扰会暂时抑制瘤胃解毒机制。结果，绵羊可能再次容易受到香豌豆中毒的影响。
