醉马草内生真菌对家兔的影响

通过饲喂试验,研究了带内生真菌(E+)和不带内生真菌(E-)的醉马草对家兔健康的影响。内生真菌的侵染,使醉马草粗脂肪含量显著提高,粗蛋白和粗纤维含量无显著改变。按10 mL/kg体重的剂量灌服E+醉马草水提液,家兔表现出明显的中毒症状；但累计灌服20 mL/kg体重的剂量,亦未引致死亡。平均按每kg体重累计饲喂E+醉马草131.6 g,可引起家兔中毒；累计饲喂350.9 g可使家兔致死,死亡率达66.7%。而灌服和饲喂E-醉马草的家兔则无异常。初步认为,醉马草对家兔的致毒机理是由内生真菌与宿主互作产生的生物碱所致。

Effects of |Drunken Horse Grass Infected with Endophyte on Chinese Rabbit

Feeding trials were conducted to evaluate effects of drunken horse grass infected with(E+) or free from (E-) endophyte, Neotyphodium gansuense, on health of rabbits. Comparedwith E- grass, the content of crude fat in E+ grass increased significantly, while nosignificant differences were detected in the contents of crude fiber and crude proteinbetween E+ and E- plants. Rabbits showed toxicity symptoms when drenched with aqueousextract obtained from E+ grass at the dose of 10~20 mL/kg body weight. However, nomortality was found even when drenched at the higher rate of E+ extracts. Feeding trialsshowed that rabbits developed toxicity symptoms when fed with E+ grass pellet ataccumulated amount of 131.6 g/kg body weight and died when they intake E+ grass pellet upto 350.9 g/kg body weight. The final tested rabbit mortality rate was 66.7％ during thefeeding period. There were no toxicity symptoms in any rabbits fed with E- plants in theforms of either aqueous or fodder pellet, which indicated that the Neotyphodium endophytewas the cause of A. inebrians toxicity to rabbits.