The Research On Food-intake Discrepancy And Its Regulation Mechanism Of Different Type Of Chickens

In the experiment, comparison about food-intake, growth, carcass characteristics, dietary apparent metabolic rate, plasma biochemistry indexes, plasma hormone levels, and digestive enzymes activities were made between AA broilers and Leghorn chicks during 3~7week, under ad libitum, food control and fasting 12h, with the arm to study on food-intake discrepancy and its regulation mechanism of different type of chickens.Experiment 1 Food-intake discrepancy and its control mechanism of different type of chickens under ad libitumThis experiment was adopt single factor completely random design, comparison about food-intake, growth and metabolism were made between AA broilers and Leghorn chicks from during 3~7 weeks under ad libitum. the results showed, different growth rates of AA broilers and Leghorn chicks were due to different food consumption and feed efficiency, Broiler chicks shown lower metabolisability of dietary DM, EE, energy, and lower digestive enzymes activities than Leghorn chicks, plasma leptin lever and NPY level in both type of chickens deceased with age increasing, and plasma leptin level of broilers were lower than Leghorn chicks in 4 week-of-age.Experiment 2 Food-intake discrepancy and its control mechanism of different type of chickens under food restrictionIn this experiment, AA broilers and Leghorn chicks received food restriction with amount of 50% and 80% of ad libitum, respectively. The effect of food restriction on growth, carcass characteristics, plasma biochemistry indexes, plasma hormone levels, and digestive enzymes activities were investigated, with the aim inquiring the food-intake discrepancy and its regulaiton mechanism of different type of chickens under food controlling. The results were as following: food restriction induced lower body weight, lower lean meat percentage and lower plasma leptin level, deceased plasma TG, ALB, CK and AST levels in broilers, deceased plasma UA level of Leghorn chicks ,and food restriction have no significant effect on digestive enzymes activities.Experiment 3 The control mechanism of food intake different type of chickens under fasting 12hIn this experiment, the effects of fasting 12 h on plasma biochemistry indexs and plasma hormones levelson AA broilers and Leghorn chicks in 48 d was investigated, with the aim inquiring the regulaiton mechanism of food intake different type of chickens under fasting 12h. The result showed that: fasting 12 h induced lower plasma UA level, and fasting 12 h induced lower plasma leptin level in Leghorn chicks but higher plasma leptin level in AA broilers.In conclusion, broilers and egg chicks had many discrepancies in food-intake, growth, carcass characteristics, dietary apparent metabolic rate, plasma biochemistry indexes, plasma hormone levels, and digestive enzymes activities under ad libitum, food control and fasting 12h, so, different type of chickens showed different food-intake and different regulation mechanism.