Study On Energy Nutrition Requirements Of Guanzhong Dairy Goats At The Age Of 1～90 Days

Three experiments were carried out in this study: (1) the digestibility and metabolic rate of energy in four category feeds for different age guanzhong dairy goats.(2) energy nutrition requirements of guanzhong dairy goats at the age of 1~90 days. (3) optimum supplementary energy level of guanzhong dairy goats on the condition of artificial cultivation.Experiment 1: the digestibility and metabolic rate of energy in four category feeds for different age guanzhong dairy goats.16 neonatal guanzhong dairy goat lambs were selected and randomly divided into 4 groups. There are 4 lambs in each group and each lamb was a repeat. Digestion and metabolism tests were finished based on total feces and urine collection. Digestibility and metabolic rate of the major nutrient in fresh goat milk, supplementary, green hay and corn silage were determined on lambs at different age. The results showed that:(1) Apparent digestibility of energy and dry matter and energy metabolism of guanzhong dairy goats at different age showed different regularity in different feed. Apparent digestibility of energy and dry matter and energy metabolism in fresh milk decreased with increasing age. Energy apparent digestibility are rising and energy metabolism are declining in supplementary, green hay and corn silage. Digestibility of energy in milk was 96.29% at 1, 2-month-old lambs, 3 months old was 89.70%. Metabolic rate of digestible energy of various feed types can not be affected by its types at 1, 2, 3-month-old lambs, respectively with 92.85%, 85.48% and 82.61%.(2) Apparent digestibility of energy and dry matter and energy metabolism of guanzhong dairy goats at the same age showed a certain regularity in different feed, fresh goat milk> supplement feed> corn silage> green hay.Experiment 2: energy nutrition requirements of guanzhong dairy goats at 1~90 days.64 neonatal guanzhong dairy goat lambs were selected(male , female half and half) and randomly divided into 8 groups. There are 8 lambs in each group and each lamb was a repeat. Lambs were fed in accordance with the program of cultivation of the "artificial feeding milk + ad libitum feeding supplement ". Regression analysis was done to establish regression equation of energy requirement, average daily gain (ADG) and metabolic weight (W0.75). According to the regression equation, the recommended standard of energy requirements of guanzhong dairy goat lambs was made under the conditions of different body weight (6, 8,10,12,14,16 kg) and different daily gain (0, 0.1, 0.15, 0.2 kg/d). The results showed that: With increasing age, guanzhong dairy goat lambs needs less maintenance energy requirements and more growth energy requirements.Experiment 3: optimum supplementary energy level of guanzhong dairy goats on the condition of artificial cultivation.28 neonatal, weight close, healthy disease-free guanzhong dairy goats were selected as experiment animals. The appropriate supplementary energy levels of 31~90 d guanzhong dairy goats were obtained by using computer simulation under the ideal conditions of artificial cultivation. The results showed that: With increasing age, the appropriate supplementary energy levels of 31~90 d guanzhong dairy goats increased significantly at two-month-old, but tend to stabilize at three-month-old. The appropriate supplementary digestible energy and metabolizable energy levels of two-month-old and three-month-old guanzhong dairy goats respectively are: 11.11~15.16 and 8.86~12.89MJ/kg, 13.00~15.46and 11.08~12.91MJ/kg.