摘要
Two experiments were conducted with 3- to 5-d-old Holstein male calves. In Experiment 1,15 calves were assigned to three dietary treatments. The control diet was based on sodium caseinate, lard, and cerelose. In the other diets, either 50% or all carbohydrates were replaced by lime-treated corn flour (Nixtamal). In Experiment 2, 35 calves were assigned to dietary treatments in which 0, 50, or 67% low heat skimmed milk protein was replaced by hydrolyzed fish protein; for the replacement diets, Nixtamal was incorporated at 25 or 35% of the dry matter. Control diet protein was entirely from skimmed milk. Milk substitutes provided the only feed during the 8-wk experiment. In Experiment 1, body weight gain and feed efficiency declined when Nixtamal completely replaced skimmed milk but remained unchanged at 50% substitution. Substitution of Nixtamal for skimmed milk powder decreased nitrogen and carbohydrate digestibility; but digestibility improved with age. In Experiment 2, replacing up to 67% of skimmed milk protein with partially hydrolyzed fish protein concentrate had no effect on body weight gain but decreased feed efficiency linearly at 8 wk and reduced dry matter, nitrogen, and fat digestibility. Nixtamal can replace up to 50% of skimmed milk carbohydrates without detrimental effect on growth rate, feed efficiency, and diarrhea, but digestibility might be reduced. Concurrent replacement of up to 67% of skimmed milk protein with partially hydrolysed fish protein concentrate would be feasible for newborn calves gaining 450 g/d, despite lower nitrogen digestibility.
摘要译文
用3至5日龄的荷斯坦雄性小牛进行了两次实验。在实验1,15中，将小牛分配给三种饮食处理。对照饮食基于酪蛋白酸钠，猪油和cerelose。在其他饮食中，50％或所有碳水化合物被石灰处理的玉米粉（Nixtamal）取代。在实验2中，将35只小牛分配到饮食处理中，其中0,50或67％的低热脱脂乳蛋白被水解的鱼蛋白取代;对于替代日粮，Nixtamal以25％或35％的干物质加入。控制饮食蛋白质完全来自脱脂牛奶。在8周的实验中，牛奶替代品是唯一的饲料。在实验1中，当Nixtamal完全取代脱脂乳但在50％替代时保持不变，体重增加和饲料效率下降。用Nixtamal代替脱脂奶粉可降低氮和碳水化合物的消化率;但消化率随着年龄的增长而提高。在实验2中，用部分水解的鱼蛋白浓缩物替代高达67％的脱脂乳蛋白对体重增加没有影响，但在8周线性降低饲料效率并降低干物质，氮和脂肪的消化率。 Nixtamal可以替代高达50％的脱脂牛奶碳水化合物，而不会对生长速度，饲料效率和腹泻产生不利影响，但消化率可能会降低。尽管氮消化率较低，但同时用部分水解的鱼蛋白浓缩物替代高达67％的脱脂乳蛋白对于新生牛犊可获得450克/天是可行的。
M.Diaz-Castañeda[2];G.J.Brisson;. Replacement of Skimmed Milk with Hydrolyzed Fish Protein and Nixtamal in Milk Substitutes for Dairy Calves1[J]. Journal of Dairy Science, 1987,70(1): 130-140