Purified glycerin in balanced diets of broiler chickens treated from 1 to 42 days of age

ABSTRACT We evaluated the technical feasibility of purified glycerin inclusion in balanced diets of broiler chickens treated from 1 to 42 days of age. A total of 240 broiler chickens were distributed in a completely randomized design into four treatments (0, 2, 4, and 6% purified glycerin inclusion), with six replicates of 10 broilers each. We evaluated productive performance (at 7, 21, and 42 days), edible viscera (heart, liver, and gizzard), carcass yield and cuts, color, chemical and physical composition, as well as protein and fat deposition in the breast muscle. Dietary inclusion of purified glycerin reduced feed conversion and increased feed intake, weight gain, and weight at seven days. From 1 to 21 days, there was a decrease in feed conversion and a linear increase in weight gain, with no effect on feed intake. Considering the total experimental period, increasing glycerin levels increased weight gain and weight at 42 days, with no effects on feed conversion or feed intake. Similarly, there was no effect on carcass and cut yields, liver and gizzard yields, and weight or length of the intestine, while heart yield was decreased. There was a linear increase in crude protein, ether extract, protein, and fat deposition and a reduction in moisture percentages, with no effect on ash content. Purified glycerin levels did not affect a*, b*, L*, pH, temperature, shear force, or weight loss by cooking in breast meat. The dietary inclusion of purified glycerin of up to 6% proved to be technically feasible in the diets of broilers from 1 to 42 days.

摘要 本研究评估了1至42日龄肉仔鸡全价日粮中添加纯化甘油（purified glycerin）的技术可行性。试验共选取240羽肉仔鸡，采用完全随机设计（completely randomized design）分为4个处理组（纯化甘油添加水平分别为0、2、4、6%），每组设6个重复，每个重复10羽肉仔鸡。本试验测定了肉仔鸡7、21、42日龄的生产性能，可食用内脏（心脏、肝脏、肌胃（gizzard））指标，屠宰率及分割肉性能，肉色、理化组成，以及胸肌的蛋白质与脂肪沉积情况。日粮添加纯化甘油可改善7日龄肉仔鸡的饲料转化率，并提高其采食量、日增重与体重。在1至21日龄阶段，饲料转化率有所降低，日增重呈线性提升，但采食量未受显著影响。就整个试验周期而言，甘油添加水平升高可提升42日龄肉仔鸡的日增重与体重，但对饲料转化率及采食量无显著影响。同理，该添加方式对屠宰率、分割肉得率、肝脏及肌胃产率、肠道重量与长度均无显著影响，但心脏产率有所降低。胸肌的粗蛋白质、乙醚浸出物（ether extract，粗脂肪）及蛋白质、脂肪沉积量呈线性提升，而水分含量有所降低，灰分含量未受显著影响。胸肌的a*值、b*值、L*值、pH值、温度、剪切力及蒸煮损失率均未受纯化甘油添加水平的显著影响。综上，在1至42日龄肉仔鸡日粮中添加最高6%的纯化甘油，在技术上具备可行性。