选用50只2月龄新西兰兔分成5组，饲喂5种消化能(DE，MJ/kg)水平的日粮(分别为9.46、10.46、11.46、12.46和13.46)，测定了日粮消化能水平对2～3月龄新西兰兔生产性能、营养物质消化利用、免疫指标、小肠酶活性、盲肠内环境和肉质的影响.结果表明：日粮能量水平对日增重、料肉比影响显著(P＜0.05)，日增重以10.46MJ/kg组最大，为29.28g，料肉比随能量水平升高而降低；日粮能量水平对试验兔除灰分消化率外都有显著影响(P＜0.05)，粗蛋白(CP)消化率、氮沉积以10.46MJ/kg组最大，粗纤维(CF)和能量消化率随日粮能量水平升高而升高，脂肪和灰分消化率则随日粮能量水平升高而降低；能量水平对3月龄肉兔免疫指标影响不显著；小肠淀粉酶和脂肪酶活性随能量水平升高而增加(P＜0.05)；3月龄试兔盲肠内pH值、NH3-N浓度、丙酸比例和丁酸比例均随日粮能量水平升高而增加，总挥发性脂肪酸浓度(TVFA)、乙酸比例、乙丙酸比则随日粮能量水平升高而减少，其中能量水平对pH值、NH3-N含量、丁酸比例、乙酸比例的影响显著(P＜0.05)，而对丙酸比例、TVFA和乙、丙酸比影响极显著(P＜0.01)；能量水平对3月龄肉兔半净膛、全净膛屠宰率无显著影响(P＞0.05)，对屠体重、全净膛重、眼肌面积影响显著(P＜0.05)，其中屠体重以10.46MJ/kg组最高；能量水平对肉兔背最长肌pH值、系水力、剪切值、蛋白质和灰分含量影响不显著(P＞0.05)，肉中脂肪含量随日粮能量水平升高而有所增加，对肉豆蔻酸、棕榈酸、棕榈油酸的含量影响不显著(P＞0.05)，兔肉硬脂酸、油酸和亚油酸含量均随日粮能量水平升高而增大(P＜0.05).综合以上研究结果，以日增重、料肉比、氮沉积和屠体重为主要经济指标，2～3月龄肉兔适宜的消化能水平为10.46MJ/kg.

The experiment was carried out to study the effects of different age on production performance, nutrient digestibility, immunity index and small intestine protease activities of New Zealand rabbits. Twenty weaned rabbits were raised and the rabbits were allocated to weaning to 2 months and 2 to 3 months. The results showed as following: The average daily gain of weaning to 2 months rabbits was higher than that of 2 to 3 months (p<0. 05), which are 33. 4g and 29. 6g; the feed/gain rate of weaning to 2 months rabbits was lower than that of 2 to 3 months (p<0. 05), which are 2. 93: 1 and 4. 41: 1. The nutrient apparent digestibility of 2-3 months rabbits was higher than that of weaning-2 months, there into, the average apparent digestibility of crude protein of 2-3 months and weaning-2 months were 72. 0% and 68. 1%, respectively. The average nitrogen retention of 2-3 months and weaning-2 months were 1. 5g/d and 1. 3g/d. The immunity index of different age rabbits has not obvious change, the protease activities descended when age increased.

An experiment was conducted to determine the effects of different dietary neutral detergent fibre (NDF) levels on growth performance, nutrient utilization, caecum development, caecal fermentation, slaughter performance, immune organ and fibrolytic activity in 2- to 3-month-old New Zealand meat rabbits. Eighty 2-month-old rabbits were allocated in individual cages for five treatments in which they were fed each diet with NDF at 240, 270, 300, 330 and 360 g/kg respectively. The results are as follows: the average daily gain of 300 g/kg NDF group was the highest (30. 09 g/day) and higher than that of 240 g/kg NDF group (p < 0. 05). The feed/gain ratio of 300 g/kg NDF group was the lowest (4. 27) and lower than those of 240 and 360 g/kg NDF groups (p < 0. 05). The coefficient of total tract apparent digestibility (CTTAD) of energy, crude protein, crude fibre and ether extract decreased when1dietary NDF increased (p < 0. 05); CTTAD of NDF increased when diet2ary NDF increased (p < 0. 01). Digestible nitrogen and retained nitrogen of 240, 270, 300 and 330 g/kg NDF groups were higher than that of 360 g/kg NDF group (p < 0. 05). The caecum weight, the proportion of caecum weight to body weight and the acetic acid ratio of volatile fatty acid rose when dietary NDF concentration increased (p < 0. 05). The NH3-N concentration of caecum dropped when dietary NDF increased (p < 0. 05). The fibrolytic activity increased when the dietary NDF increased (p < 0. 01).

选取24只体重3.5kg左右的健康安哥拉兔，随机分为3组，分别饲喂氮硫比为9.99：1、7.91：1和5.97：1的全价日粮，研究了不同氮硫比对安哥拉兔营养物质利用、产毛性能和血清尿素氮及胆固醇含量的影响。试验结果表明：氮硫比为7.91：1时，日粮干物质(DM)和有机质(OM)的消化率最高，氮硫比为9.99：1时，日粮酸性洗涤纤维(ADF)的消化率最高；随着氮硫比的降低，沉积氮、可消化氮转化为沉积氮的效率和氮的表观消化率均下降(P＜0.05)，以氮硫比为9.99：1组最高，分别为1.24g/d、50%和62%；日粮氮硫比为9.99：1时，安哥拉兔产毛性能最好，估测年产毛量为862.67g，平均毛长为5.44cm，血液尿素氮含量最高为131.11mg/DL；随着日粮氮硫比的降低血清尿素氮含量有降低的趋势(P＞0.05).日粮中不同氮硫比胆固醇含量水平无规律性变化。

将80只断奶肉兔随机分成5组，饲喂5种消化能不同(9.46，10.46，11.46，12.4和13.46MJ/kg)的日粮。结果表明：能量水平对2月龄体重、断奶至2月龄日增重无显著影响(P>0.05)，2月龄体重、断奶至2月龄日增重以能量水平为10.46MJ/kg时最高，分别为1638g和25g；能量消化率和脾脏指数随能量水平不同而变化差异显著(P<0.05)；盲肠pH值、NH3-N浓度、丙酸含量、TVFA和乙酸/丙酸比组间差异极显著(P<0.01)，乙酸和丁酸含量组间差异显著(P<0.05)。以日增重、蛋白质消化率等指标为依据，断奶至2月龄肉兔适宜消化能水平为10.46MJ/kg。