生长猪对转基因豆粕外源DNA的代谢研究

Study on Metabolism of Exogenous DNA from Transgenic Soybean Meal in Grower Pigs

研究了抗草甘膦转基因豆粕中的外源DNA在生长猪体内的代谢和沉积。选用去势公猪,于回肠末端安装简单T型瘘管,饲喂常规和转基因豆粕日粮,收集回肠食糜和粪便;另外进行生长猪饲喂试验42 d,添加约30%常规或转基因豆粕,屠宰后采取组织样品,检测外源DNA残留。结果表明,在回肠食糜和粪便中检出源自抗草甘膦豆粕的外源cp4epsps基因,但重现率均仅有6.7%,外源DNA的完整性在小肠后段很大程度上受到破坏;PCR检测下限为5 pg时,在生长猪肝脏、肌肉、脾脏和胸腺组织中无cp4epsps基因残留,外源DNA已被代谢降解。

Metabolism and deposition of exogenous DNA from transgenic glyphosate-tolerant soybean meat in grower pigs were studied in the experiment. The conventional and transgenic soybean meal diets were fed to barrows fitted with a simple T-cannula at distal ileum for collection of ileal chyme and feces. In addition, feeding experiment with 30% of conventional or transgenic soybean meal was performed in grower for 42d. Then the tissue samples were obtained after slaughter for detection of exogenous DNA. The results showed that the exogenous gene cp4 epsps derived from glyphosate-tolerant soybean meal was detected in chyme and feces both only at 6.7%, which indicated that integrity of exogenous DNA was greatly or utterly devastated in distal intestine. Based on 5 pg of limit by PCR, there were no deposition of cp4 epsps gene in liver, muscle, spleen and thymus tissue of grower, and this implied that exogenous DNA has already been metabolized and degraded.