壳聚糖对肉仔鸡血清花生四烯酸含量、磷脂酶A2活性及小肠胞内磷脂酶A2 mRNA表达的影响

摘要

The study was conducted to determine the effects of chitosan on content of arachidonic acid and the activity of phospholipase A2(PLA2) in serum, and relative expression of cytosolic phospholipase A2(cPLA2) mRNA in duodenum, jeju-num, and ileum of broilers.Two hundred and forty one-day-old Arbor Acre broilers were randomly allotted to six treatments with five replicates each and eight chickens in each replicate.Six groups were prepared for the study.Control group was the basal diet without chitosan.The other five groups were formulated by the addition of 50, 200, 500, 1 000 and 2 000 mg/kg of chitosan to the basal diet, respectively.The trial lasted for 42 days.The results showed that chitosan improved the con-tent of An, and the activity of PLA2 in serum, and also the expression of cPLA2 mRNA in duodenum, jejunum, and ileum of broilers in a quadratic dose-dependent manner (P<0.05), and the supplementation of 500 and 1 000 mg/kg chitosan to the diet were more effective.However, the supplementation of 2 000 mg/kg chitosan to diet was less effective.It was concluded that it was probably related to the improvement of PLA2 activity and the expression of cPLA2 mRNA in small intestine that chitosan may improve the immune function of broilers.%本试验旨在研究日粮中添加不同水平壳聚糖对肉仔鸡血清花生四烯酸含量、磷脂酶A2活性及小肠胞内磷脂酶A2mRNA表达的影响.试验选择1日龄健康爱拔益加肉仔鸡240只(公母各占1/2),随机分为6个处理,每个处理5个重复,每个重复8只鸡.对照组饲喂基础日粮,其他5种试验日粮分别在基础日粮中添加50、200、500、1000和2 000 mg/kg的壳聚糖配制而成.试验期42 d.结果表明,肉仔鸡血清花生四烯酸含量、磷脂酶A2活性及十二指肠、空肠、回肠的胞内磷脂酶A2mRNA表达均随日粮壳聚糖添加量的增加呈显著二次曲线增加(P<0.05);其中以500和1 000 mg/kg壳聚糖组较高,但当日粮壳聚糖添加量为2 000 mg/kg时则有不同程度的降低.由此可知,壳聚糖对肉仔鸡免疫功能的影响可能与磷脂酶A2的活性及小肠胞内磷脂酶A2mRNA的表达发生改变有关.