7种饲料原料粉碎粒度与蛋白质体外消化率及能耗的研究

选择 7种饲料原料 (玉米、麸皮、去皮豆粕、带皮豆粕、普通豆粕、棉粕、菜粕 ) ,用小型锤片粉碎机在 5种孔径(4 .0、2 .5、1.5、1.0、0 .6mm)的筛片下进行粉碎 ,测定粉碎物的对数几何平均粒度和粉碎电耗 ,并用胃蛋白酶 -胰蛋白酶两步体外消化法测定不同粉碎物的蛋白质的胃蛋白酶消化率和两种酶的连续消化率。结果表明 :(1) 7种饲料原料粉碎物的对数几何平均粒度与粉碎机筛片孔径线性相关 ,但也与饲料原料的原始粒度有关 ;(2 )粉碎能耗与粉碎物对数几何平均粒度主要呈二次曲线关系 ,当原料粉碎通过 1mm及以下筛孔时 ,电耗急剧上升 ;(3)粉碎物的胃蛋白酶体外消化率和总酶消化率与粉碎物的几何平均粒度显著线性负相关 (P <0 .0 5 )。说明粉碎能有效提高饲料蛋白质的消化率。其中 ,去皮豆粕具有最高的蛋白质体外消化率。

Effects of Particle Sizes on in itro Protein Digestibility and Energy Consumption of Seen Feed Ingredients

feed ingredients(corn,wheat bran,dehulled soybean meal,soybean meal,cotton seed meal and rapeseed meal)were grounded through 5 kinds of meshes of screen,the average geometric particle size(AGPS),power consumption and pepsin-pancreatin digestibility in vitro of each ground product were measured.The results indicated that:(1)The AGPS of 7 feed ingredients are Linearly correlated with the grinding mesh size,and also relative with the original particl size of the ingredients;(2)The relationship between grinding energy consumption and the AGPS of the ingredients are mostly quadratic equations;(3)The pepsin digestibility and the total digestibility of pepsin-pancreatin in vitro are negatively linearly correlated with the AGPS of the ingredients(P<0.05).