维生素A对青农灰鹅屠宰性能和免疫性能的影响

试验选用1日龄青农灰鹅200只,随机分为5个处理,每处理4个重复,每重复10只。在玉米-豆粕型日粮基础上分别添加0(Ⅰ组)、1500(Ⅱ组)、3000(Ⅲ组)、6000 IU/kg(Ⅳ组)和12000 IU/kg(Ⅴ组)的维生素A,试验期为12周。结果表明:日粮添加维生素A能显著提高12周龄青农灰鹅屠宰率、全净膛率、半净膛率(P<0.05),但对4周龄鹅屠宰性能的影响不显著(P>0.05);基础日粮添加维生素A能极显著提高4周龄青农灰鹅胸腺指数及淋巴细胞转化率(P<0.01),显著提高12周龄胸腺指数(P<0.05),极显著提高12周龄法氏囊指数和淋巴细胞转化率(P<0.01),日粮添加维生素A能显著提高免疫后7、14 d鹅禽流感抗体效价(P<0.05)。结果显示,日粮中添加维生素A可提高青农灰鹅的屠宰性能和免疫性能。综合各项指标,本试验条件下,0～4周龄和5～12周龄维生素A添加水平均以7000 IU/kg为宜。

Effects of vitamin A supplemented in basal diets on slaughter performance and immune function in geese

Two hundred 1-day-old Qingnonghui geese were selected and divided into 5 treatments with 4 replicates of 10 geese in each replicate.Five treatments were supplemented with 0(Group I),1500(Group Ⅱ),3000(Group Ⅲ),6000 IU/kg(Group IV)and 12000 IU/kg(Group V) vitamin A in the basal diets,respectively.The experiment lasted for twelve weeks.The results showed that:vitamin A could significantly increase dressing percentage,and percentage of semi-eviscerated yield at the age of 12 weeks(P < 0.05),but had no significant effects on slaughter performance at the age of 4 weeks(P > 0.05).At the age of 12 weeks,vitamin A could significantly increase thymus index and the transformation rates of peripheral blood T lymphocyte(P < 0.01).At the age of 12 weeks,the thymus index was increased significantly(P < 0.05),the bursa index and the transformation rates of peripheral blood T lymphocyte were extremely reduced significantly by adding a certain level of vitamin A(P < 0.01).Vitamin A could significantly increase the antibody titre of Bird flu disease at the 7th,14th day after immunization(P < 0.05).So adding a certain level of vitamin A in the basal diet could improve slaughter performance and immune function.In conclusion,under this experimental condition,the optimal level of vitamin A in diet was recommended as 7000 IU/kg in 0 ~ 4 week and 5 ~ 12 weeks.