| New Zealand (NZ) Rabbits were subjected to experiment with one factor at five levels of dietary energy and feeding two stages. 80 NZ rabbit which weight were all colsed were randomly divided into five groups.Each group of rabbit was feed one energy level dietary.The dietary energy of five groups were 9.46MJ DE/kg,10.46 MJ DE/kg,11.46 MJ DE/kg,12.46 MJ DE/kg,13.46 MJ DE/kg respectively. Except the energy ,other nutrient compositions in the five dietarys were identical. The total feeding course was divided into two stages.The earlier stage was from weaning to 2-month old, and the later stage was from 2-month old to 3-month old, and the total experiment stage was 55 days. The growth and development function,produce function,nutrient matter digestion and utility,immunity index,activity of small intestine digestive enzyme,the interior environment of caecum and slaughter rate and carcass quality were determined and analyzed at each test stage. The results were followed: The results when the NZ rabbit were reared from weaning to 2-month old indicated that: energy level had not significantly influence on body weight of 2-month NZ rabbit (P>0.05);the average daily gain was 23.40g; the energy level had significantly influnce on feed conversion rate (P<0.05) ,the energy level was 9.46MJ DE/kg when feed conversion rate was largest.Eenergy level affect the utility of nutrient matters significantly (P<0.05);the digestbility of crude protein and protein retention of the sencond group were largest, and they were: 82.77% and 60.49% respectively.;The digesbility of crude fat,crude ash were reduced with the energy level increased. The energy level had significant influence (P<0.05) on spleen index, but it had extreme significantly influnceon W-SCR,W-SCC,WBC(P<0.01);the energy level had not significant influnce on thymus index,RBC and HGB (P>0.05). The amylase activity and lipase activity were increased with the energy level increased, and the effect of energy level on amylase activity was significant (P<0.05) but on lipase activity was not significant (P>0.05). The value of pH,the NH3-N content,acetone content and butyric acid content were increased with the energy level increased; the value of TVFA,acetic acid content and the rate of acetic acid to propionic acid were increased with the energy level reduced;the difference of the value of pH,NH3-N content,propionic acidcontent,TVFA content and the rate of acetic acid to propionic acid in different groups were extreme significant (P<0.01), and the difference of acetic acid content and butyric acid content in different groups were significant (P<0.05)。 The results when the NZ rabbits were reared from 2 to 3 month old. indicated that : energy level had no influnce on body length and chest measurement of 3-month old NZ rabbit but it had significant influnce on daily gain and feed conversion rate (p<0.05); when energy was 10.46 MJ DE/kg, daily gain was largest and it was 27.59g; with the increasing of the energy level,FCR reduced. Except ash digestibility ,energy level had significant influnce on other nutrient digestibility (p<0.05), when dietary energy was 10.46 MJ DE/kg ,crude protein digestibility and nitrogen deposition were highest ; with the increase of the energy level,crude fibre digestibility and energy digestibility and metabolity were incread but fat and ash digestibility were reduced .Compared with weaning~2 month old , the nutrient digestibility were little low except fat . Except HGB,energy level had no significant influnce on other immunity indexs; when dietary energy was 11.46 MJDE/kg ,thymus index and spleen index were highest; when dietary energy was 12.46 MJ DE/kg, W-SCR,W-SCC,WBC and HGB were highest . The energy level had no significant influnce on amylase and lipase activity (p>0.05),but the two kinds of enzyme were increased with the energy level reduced. With the increase of the energy level , value of pH,NH3-N content,acetone content and butyric acid content were increased ,but TVFA,acetic acid and the rate...
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