饲粮蛋氨酸水平对9－10月龄豪猪生长性能、血清免疫指标及抗氧化指标的影响

Effects of Dietary Methionine Level on Growth Performance,Serum Immune Indices and Antioxidant Indices of 9 to10-Month-Old Porcupine

本试验旨在探讨饲粮蛋氨酸水平对9-10月龄豪猪生长性能、血清免疫指标及抗氧化指标的影响,并利用二次回归模型估测其蛋氨酸需要量。选择体重相近的9月龄豪猪96头,随机分成6组,每组4个重复,每个重复4头,分别饲喂蛋氨酸水平为0.25%、0.45%、0.65%、0.85%、1.05%和1.25%的试验饲粮。预试期7 d,正试期50 d。结果表明：1）饲粮蛋氨酸水平对豪猪平均日增重（ADG）和平均日采食量（ADFI）没有显著影响（P〉0.05）,但对料重比（F/G）有显著影响（P〈0.05）。随着饲粮蛋氨酸水平的升高,F/G呈先降低再升高的二次曲线变化趋势,在蛋氨酸水平为0.85%时达到最小值3.63。2）饲粮蛋氨酸水平对豪猪血清免疫球蛋白A（Ig A）、免疫球蛋白G（Ig G）、免疫球蛋白M（Ig M）含量及超氧化物歧化酶（SOD）活性均无显著影响（P〉0.05）,但显著影响血清谷胱甘肽过氧化物酶（GSH-Px）活性（P〈0.05）,极显著影响血清丙二醛（MDA）含量（P〈0.01）。随着饲粮蛋氨酸水平的升高,血清GSH-Px活性呈先增加再降低的二次曲线变化趋势,在蛋氨酸水平为0.85%时达到最高值。随着饲粮蛋氨酸水平的升高,血清MDA含量呈现先降低再升高的二次曲线变化趋势,其中0.85%和1.05%组极显著低于0.25%、0.45%和0.65%组（P〈0.01）,1.25%组极显著低于0.25%和0.45%组（P〈0.01）。综上所述,饲粮中添加适量的蛋氨酸可改善9-10月龄豪猪的生长性能,提高其抗氧化能力。根据二次回归模型估测,9-10月龄豪猪获得最低F/G、最高血清GSH-Px活性和最低血清MDA含量的蛋氨酸需要量分别为0.76%、0.87%和0.96%。

This study was conducted to investigate the effects of dietary methionine（M et） level on growth performance,serum immune indices and antioxidant indices of 9 to 10-month-old porcupine,and to determine the M et requirement of 9 to 10-month-old porcupine based on quadratic regression model.Ninety-six 9-month-old porcupines with the similar body weight were randomly assigned to 6 groups with 4 replicates per group and each replicate contained 4 individuals.Porcupines in 6 groups were fed experimental diets with 0.25%,0.45%,0.65%,0.85%,1.05% and 1.25% M et,respectively.The adaption period lasted for 7 days and the trail period lasted for 50 days.The results showed as follows：1） dietary M et level did not significantly affect average daily gain（ADG） and average daily feed intake（ADFI）（P〉0.05） of porcupine,but significantly affected feed/gain（F/G）（P〈0.05）.W ith the increase of dietary M et level,the F/G showed the tendency of a quadratic curve dropped firstly and then increased,and it had the minimum value of 3.63 when the M et level was0.85%.2） Dietary M et level had no significant effects on the contents of immunoglobulin A（Ig A）,immunoglobulin G（Ig G）,immunoglobulin M（Ig M） and the activity of superoxide dismutase（SOD） in serum（P〉0.05）,but significantly affected the activity of glutathione peroxidase（GSH-Px）（P〈0.05） and the content of malonaldehyde（M DA） in serum（P〈 0.01）.W ith the increase of dietary M et level,the activity of serum GSH-Px showed the tendency of a quadratic curve increased firstly and then decreased,and it had the maximum value when the M et level was 0.85%.The serum M DA content showed the tendency of a quadratic curve dropped firstly and then increased with the increase of dietary M et level.The content of serum M DA in the groups with 0.85% and 1.05% M et were significantly lower than those in the groups with 0.25%,0.45% and0.65% M et（P 〈0.01）.The content of serum M DA in the group with 1.25% M et was significantly lower than that in the groups with 0.25% and 0.45% M et（P 〈0.01）.In conclusion,dietary supplemented with proper M et can improve the growth performance and enhance the antioxidant ability of 9 to 10-month-old porcupine.The estimated M et requirements of 9 to 10-month-old porcupine to gain the minimum of F/G,the maximum of serum GSH-Px activity and the minimum of serum M DA content are 0.76%,0.87% and 0.96% base on quadratic regression model,respectively.