National Engineering Research Center for Breeding Swine Industry, College of Animal Science, South China Agricultural University, Guangzhou, 510642, China.
College of Life Science, Longyan University, Longyan, 364012, China.
Transgenic Res. 2019 Apr;28(2):189-198. doi: 10.1007/s11248-019-00110-z. Epub 2019 Jan 14.
Xylan is one of the main anti-nutritional factors in pig's feed. Although supplementation of β-xylanase in diet can improve the utilization of nutrients in animals, it is limited by feed cost, manufacturing process and storage stability. To determine whether the expression of endogenous β-xylanase gene xynB in vivo can improve digestibility of dietary xylan and absorption of nutrients, we produced transgenic pigs which express the xynB from Aspergillus Niger CGMCC1067 in the parotid gland via nuclear transfer. In four live transgenic founders, β-xylanase activities in the saliva were 0.74, 0.59, 0.37 and 0.24 U/mL, respectively. Compared with non-transgenic pigs, the content of crude protein (CP) in feces reduced by 15.5% (P < 0.05). Furthermore, in 100 of the 271 F1 pigs the xynB gene was detectable. The digestibility of gross energy and CP in F1 transgenic pigs were increased by 5% and 22%, respectively, with the CP content in feces decreased by 6.4%. Taken together, our study showed that the transgenic pigs producing β-xylanase from parotid gland can reduce the anti-nutritional effect in animal diet and improve the utilization of nutrients.
木聚糖是猪饲料中的主要抗营养因子之一。虽然在饲料中添加β-木聚糖酶可以提高动物对营养物质的利用率，但受到饲料成本、制造工艺和储存稳定性的限制。为了确定内源性β-木聚糖酶基因 xynB 在体内的表达是否可以提高日粮木聚糖的消化率和营养物质的吸收，我们通过核转移在腮腺中表达来自黑曲霉 CGMCC1067 的 xynB ，从而产生了表达 xynB 的转基因猪。在 4 头活体转基因创始猪中，唾液中的β-木聚糖酶活性分别为 0.74、0.59、0.37 和 0.24 U/mL。与非转基因猪相比，粪便中粗蛋白（CP）的含量减少了 15.5%（P<0.05）。此外，在 271 头 F1 猪中有 100 头可检测到 xynB 基因。F1 转基因猪的总能和 CP 消化率分别提高了 5%和 22%，粪便中 CP 的含量降低了 6.4%。总之，我们的研究表明，从腮腺中产生β-木聚糖酶的转基因猪可以减轻动物饲料中的抗营养作用，提高营养物质的利用率。
