罗曼鸡可利用蛋氨酸维持需要的研究

试验选用30周龄罗曼公、母鸡72只,分为12个处理,每个处理6个重复,每个重复1只试鸡,单笼饲养,分别饲喂蛋氨酸水平为理想需要量的36%、50%、65%、75%、85%和100%的半纯合梯度日粮,建立蛋白质和蛋氨酸沉积量对蛋氨酸食入量间的回归方程,来确定30周龄罗曼公母鸡的可利用蛋氨酸维持需要量。结果表明:公鸡蛋白沉积量显著高于母鸡(P<0.05)。分别以蛋白质和蛋氨酸沉积量为因变量,所得公鸡可利用蛋氨酸维持需要分别为每天39.34mg/kgBW0.7(5或表示为266.81mg/kgBPM)和1.93mg/kgBW0.7(5或表示为13.11mg/kgBPM)。母鸡可利用蛋氨酸维持需要分别为每天52.32mg/kgBW0.7(5或表示为282.14mg/kgBPM)和7.76mg/kgBW0.7(5或表示为41.87mg/kgBPM);由蛋白质沉积量为因变量所得的回归方程外推零蛋白质沉积时的蛋氨酸维持需要量要显著高于以零蛋氨酸沉积所得的维持需要量(P>0.05),母鸡可利用蛋氨酸维持需要高于公鸡的测定结果。

Study on Available Methionine Maintenance Requirements for Lohmann Brown Roosters and Laying Hens

A total of 36 roosters and 36 laying hens with 30-week-age(12 dietary treatments with 6 replicate pens, 1 bird for each pen) were raised in individual cage and fed with semi-purified diets (methionine was supplied at the levels of 36, 50, 65, 75, 85 and 100% of ideal level, protein level was 12%). The experiment was conducted to establish the linear regression equations (protein and methionine accretion responses vs methionine intake), to determine available methionine maintenance requirement for Lohmann brown laying hens and roosters. The results showed that the protein accretion for roosters was higher than that of layers(P < 0.05).The daily available methionine maintenance requirement was 39.34 mg/kg BW0.75 and 266.81 mg/kg body protein mass (BPM) for zero protein accretion, 1.93 mg/kg BW0.75 and 13.11 mg/kg BPM for zero methionine accretion for adult roosters, respectively. Whereas available methionine maintenance requirement for layers was 52.32 mg/kg BW0.75 and 282.14 mg/kg BPM for zero protein accretion, 7.76 mg/kg BW0.75 and 41.87 mg/kg BPM for zero methionine accretion, respectively. The available methionine maintenance requirement based on zero methionine accretion was lower than that of zero protein accretion(P < 0.05). The available methionine maintenance requirement for layers was higher than that of roosters.