笼养蛋鸭舍环境因子与鸭免疫机能及生产性能的研究

试验检测了春季蛋鸭笼养舍内环境因子分布和蛋鸭生理机能及生产性能变化,为蛋鸭阶梯式笼养模式提出改进建议。结果表明:(1)蛋鸭舍内气载有害菌和粉尘浓度随纵向通风进程持续升高,上层鸭笼大肠杆菌属细菌气溶胶浓度显著低于中层和下层(P<0.05)。平均光照强度自进风口到出风口分布均匀,但上层笼极显著高于下层(P<0.01);(2)上层蛋鸭平均产蛋率(69.37%)显著高于下层蛋鸭(P<0.05);累计死淘率(0.11%)显著低于下层蛋鸭(P<0.05);(3)上层鸭蛋哈氏单位为68.2,极显著高于下层鸭蛋(P<0.01);(4)上层蛋鸭血清过氧化氢酶(CAT)活性、下丘脑GnRH基因表达水平均显著高于下层蛋鸭(P<0.05);下丘脑CRH基因表达水平,脾脏IL-1β、IL-10和TNF-α基因表达水平显著低于下层蛋鸭(P<0.05)。以上结果显示,春季笼养蛋鸭舍内,不同空间位置环境因子分布不均匀,下层蛋鸭长期处于恶劣环境,增加了死亡率,降低了产蛋率和蛋品质。

Study on Environmental Factors in Relation to Immune Status and Production Performance of Layer Ducks Maintained in Battery Cages

This experiment studied the environmental parameters in the caged duck house in relation to duck egg laying performance, serum antioxidant catalase(CAT) levels, and mRNA expression levels of immune function genes of the layer ducks. The results showed that the average house temperature, concentration of bacteria and dust particles increased along the ventilation orientation. Airborn E. coli concentration at high level cages was significantly(P<0.05) lower than those at the middle and low levels, but light intensity distributed evenly from the air inlet to outlet, and it was significantly higher in high level of cage than low level(P<0.01). The ducks at high level cage had higher(P<0.05) egg laying performance 69.37 than those at low level cage, higher(P<0.01) egg Haugh unit 68.2 than low level, but lower(P<0.05) mortality rate(0.11%).The serum CAT activity of ducks at high level cage was also higher(P<0.05) than that in the low level cage, so were mRNA expression levels of GnRH in the hypothalamus and LH in the pituitary gland. On the contrary, mRNA expression levels of CRH in the hypothalamus, and IL1-β, IL-10, TNF-α in the spleen were lower(P<0.05) in high level than in low level cage.The above results show environmental factors distributed unevenly at different positions of the house in spring.The long term life in worse environment of lower level of the house in creased the mortality of ducks and decreased theiregg laying rate and egg quality.