关键词: 蛋鸡, 苜蓿皂甙, 鸡蛋品质, 蛋黄颜色, 蛋黄胆固醇

Abstract:

This experiment was conducted to study the effects of alfalfa saponins on egg qualities of laying hens. 480 healthy Hailanhe laying hens of 23-weeks-old were randomly divided into 8 groups with five replicates and 12 layers per replicates. The trial lasted 45 days. The negative control group were fed with basal diet, the positive control groups were fed with the test diet supplied with 5% alfalfa meal, the other six groups were fed with the basal diets added with 500, 1 000, 1 500, 2 000, 2 500 and 3 000 mg of alfalfa saponins (the content of total saponins was 34%) per kilogram. The results showed that:neither alfalfa saponins nor alfalfa meal had significant and regular effects on egg weight, egg shape index, egg yolk index, eggshell relative weight, egg yolk relative weight and eggshell thickness. Alfalfa meal could significantly improve yolk color, but in the alfalfa saponins treatments had insignificance decrease on yolk color. The egg yolk color of alfalfa meal group were higher than that of control group and test groups, and had significant increase to all the test groups at 15 d and 45 d in the experiment (P<0.05); neither alfalfa saponins nor alfalfa meal had significant and regular effects on the egg yolk cholesterol concentration and egg cholesterol concentration; but the egg yolk cholesterol concentration of all the test groups and alfalfa meal group have insignificance decrease to that of control group at 15 d, 30 d and 45 d in the experiment, and the egg cholesterol concentration of all the test groups and alfalfa meal group have insignificance decrease to that of control group at 15 d and 45 d in the experiment. In summery, alfalfa saponins had no effects on general egg qualities,egg yolk cholesterol concentration and egg cholesterol concentration.

Key words: Laying hens, Alfalfa saponins, Egg quality, Yolk color, Egg yolk cholesterol