本试验旨在研究饲粮蛋氨酸水平对28~70日龄狮头鹅血清生化指标及抗氧化功能的影响。选择720只28日龄的健康狮头鹅,随机分为6组,每组6个重复,每个重复20只鹅。各组分别饲喂蛋氨酸水平为0.26%、0.36%、0.46%、0.56%、0.66%、0.76%的试验饲粮。试验期42 d。结果表明:1)饲粮蛋氨酸水平对平均日增重和平均日采食量影响不显著(P>0.05),0.56%和0.66%蛋氨酸水平组料重比显著低于0.26%蛋氨酸水平组(P<0.05)。2)饲粮蛋氨酸水平对血清总蛋白、白蛋白、球蛋白、尿酸、甘油三酯和高密度脂蛋白含量影响不显著(P>0.05)。0.76%蛋氨酸水平组血清低密度脂蛋白含量显著低于0.26%蛋氨酸水平组(P<0.05),但与其余各组差异不显著(P>0.05)。3)0.66%蛋氨酸水平组血清谷胱甘肽过氧化物酶活性显著高于其余各组(P<0.05);0.66%蛋氨酸水平组血清谷胱甘肽含量与0.76%蛋氨酸水平组差异不显著(P>0.05),但显著高于其余各组(P<0.05);0.66%蛋氨酸水平组血清超氧化物歧化酶活性显著高于0.26%蛋氨酸水平组(P<0.05),血清丙二醛含量显著低于0.26%、0.36%蛋氨酸水平组(P<0.05)。4)随着饲粮蛋氨酸水平提高,血清谷胱甘肽过氧化物酶活性呈二次曲线升高(P<0.05),估测饲粮蛋氨酸水平为0.654%时,28~70日龄狮头鹅血清中谷胱甘肽过氧化物酶活性达最大值。由此可见,提高饲粮蛋氨酸水平可以显著提高28~70日龄狮头鹅抗氧化功能,饲粮蛋氨酸适宜水平为0.66%。

This experiment was conducted to study the effects of dietary methionine level on serum biochemical indices and antioxidant function of lion head geese aged 28 to 70 days. Seven hundred and twenty 28-day-old healthy lion head geese were randomly divided into 6 groups with 6 replicates per group and 20 geese in each replicate. Geese in the 6 groups were fed experimental diets containing 0.26%, 0.36%, 0.46%, 0.56%, 0.66% and 0.76% methionine, respectively. The experiment lasted for 42 days. The results showed as follows: 1) dietary methionine level had no significant influence on average daily gain and daily feed intake (P>0.05), the ratio of feed to gain in 0.56% and 0.66% methionine level groups was significantly lower than that in 0.26% methionine level group (P<0.05). 2) Dietary methionine level had no significant influence on the contents of total protein, albumin, globulin, uric acid, triglyeride and high density lipoprotein in serum (P>0.05). The serum low density lipoprotein content in 0.76% methionine level group was significantly lower than that in 0.26% methionine level group (P<0.05), but compared with the other groups, that had no significant difference (P>0.05). 3) The serum glutathione peroxidase (GSH-Px) activity in 0.66% methionine level group was significantly higher than that in other groups (P<0.05); the serum glutathione hormone content in 0.66% methionine level group was significantly higher than that in other groups (P<0.05) except 0.76% methionine level group (P>0.05); the serum superoxide dismutase activity in 0.66% methionine level group was significantly higher than that in 0.26% methionine level group (P<0.05); the serum malondialdehyde content in 0.66% methionine level group was significantly lower than that in 0.26% and 0.36% methionine level groups (P<0.05). 4) With the increasing of dietary methionine level, the serum GSH-Px activity was increased quadratically (P<0.05), and the estimated methionine level for lion head geese aged 28 to 70 days was 0.654% when serum GSH-Px activity got maximum value. In conclusion, increasing dietary methionine level can improve the antioxidant function of lion head geese aged 28 to 70 days, and the optimum methionine level is 0.66%.