College of Agriculture and Forestry Science, Linyi University, Shuangling Road, Linyi City, China.
National Engineering Research Center for Breeding Swine Industry, Guangdong Provincial Key Laboratory of Agro-animal Genomics and Molecular Breeding, College of Animal Science, SCAU-Alltech Research Joint Alliance, South China Agricultural University, 483 Wushan Road, Guangzhou, 510642, China.
Transgenic Res. 2019 Apr;28(2):237-246. doi: 10.1007/s11248-019-00112-x. Epub 2019 Jan 29.
Producing heterologous enzymes in the animal digestive tract to improve feed utilization rate is a new research strategy by transgenic technology. In this study, transgenic pigs specifically expressing β-glucanase gene in the intestine were successfully produced by somatic cell nuclear transfer technology in order to improve digestibility of dietary β-glucan and absorption of nutrients. The β-glucanase activity in the intestinal juice of 4 transgenic pigs was found to be 8.59 ± 2.49 U/mL. The feeding trial results showed that the crude protein digestion of 4 transgenic pigs was significantly increased compared with that of the non-transgenic pigs. In order to investigate the inheritance of the transgene, 7 G transgenic pigs were successfully obtained. The β-glucanase activity in the intestinal juice of 7 G transgenic pigs was found to be 2.35 ± 0.72 U/mL. The feeding trial results showed the crude protein digestion and crude fat digestion were significantly higher in 7 G1 transgenic pigs than in non-transgenic pigs. Taken together, our study demonstrated that the foreign β-glucanase expressing in the intestine of the transgenic pigs could reduce the anti-nutritional effect of β-glucans in feed. In addition, β-glucanase gene could be inherited to the offsprings and maintain its physiological function. It is a promising approach to improve feed utilization by producing transgenic animals.
在动物消化道中产生异源酶以提高饲料利用率是转基因技术的一项新研究策略。本研究通过体细胞核移植技术成功生产了在肠道中特异性表达β-葡聚糖酶基因的转基因猪，以提高饲料中β-葡聚糖的消化率和营养物质的吸收率。发现 4 头转基因猪的肠液中β-葡聚糖酶活性为 8.59±2.49 U/mL。饲养试验结果表明，4 头转基因猪的粗蛋白消化率明显高于非转基因猪。为了研究转基因的遗传，成功获得了 7 头 G 代转基因猪。发现 7 头 G 代转基因猪的肠液中β-葡聚糖酶活性为 2.35±0.72 U/mL。饲养试验结果表明，7 G1 头转基因猪的粗蛋白消化率和粗脂肪消化率明显高于非转基因猪。综上所述，本研究表明，在转基因猪肠道中表达的外源β-葡聚糖酶可以降低饲料中β-葡聚糖的抗营养作用。此外，β-葡聚糖酶基因可以遗传给后代并保持其生理功能。通过生产转基因动物来提高饲料利用率是一种很有前途的方法。
