The Research On Energy Requirements Of Shanbei White Cashmere Goats In Non-pregnancy And Prcgnancy

The confinedness of cashmere goats has been becoming urgent at present.Shanbei whitecashmere goats were chosen as experimental animals in this study.Feeding test, digestivemetabolism test and slaughter test were conducted to determine the proper energyrequirements of Shanbei white cashmere goats during non-pregnancy, early pregnancy, andlate pregnancy respectively, in order to supply basic research data for the establishment andimprovement of feeding standards of Shanbei white cashmere goat.Experiment1. The research on energy requirements of shanbei white cashmere goats innon-pregnancyTwenty-four ewes at1.5year-old were randomly divided into four groups, which werefed concentrates with an equal crude protein level of74.0g/d and four digestible energylevels of7.6、8.3、8.9and9.6MJ/d, respectively, and the experiment lasted for40d,(including10d for adaptation). Three ewes in each group were selected for a seven-daydigestive metabolism test (all the feces and urine collected) at the end of the experiment. Theresults showed as follows:(1)The digestibility and metabolic rate of gross energy for nonpregnant ewes in fourgroups were62.45%~69.66%and51.78%~58.77%and increased with the increasing energyintake,group Ⅳ was highersignificantly than other three groups(P<0.05), group Ⅲwas highersignificantly than group Ⅰa ndⅡ(P<0.05).(2)Average daily gain of nonpregnant ewes increased significantly with the increasingGE、DE and ME intake in the condition of the same protein intake which met the normalgrowth needs(P<0.05).(3)The requirement of shanbei white cashmere goats for DE and ME of nonpregnantewes can be estimated by the fomula as follows:DE（MJ/d）=0.5070W0.75+0.0263ADG（P=0.003，R~2=0.9995）and ME（MJ/d）=0.4130W0.75+0.0245ADG（P=0.005，R~2=0.9992）,and in normal production conditions, the appropriate levels of DE and ME were9.17~10.14MJ/kg and7.70~8.60MJ/kg(air dry basis) respectively.Experiment2. The research on energy requirements of shanbei white cashmere goats inearly pregnancyTwenty pregnant ewes were randomly divided into four groups, which were fed concentrates with an equal crude protein level of74.0g/d and four digestible energy levels of7.6,8.3,8.9and9.6MJ/d, respectively, and the experiment lasted for90d. One ewe selected randomly from eachgroup were slaughtered at the end of the experiment. The results showed as follows:(1) Average daily gain of early pregnant ewes increased significantly with the increasingGE、DE and ME intake in the condition of the same protein intake which met the normalgrowth needs(P<0.05).(2)Energy requirements of Shanbei white cashmere goat during early pregnancy ismainly consistent with that of non-pregnancy. During early pregnancy ewes can becompletely in accordance with feeding standard of the non-pregnancy.Experiment3. The research on energy requirements of shanbei white cashmere goats inlate pregnancyTwenty ewes pregnant for90d were randomly divided into four groups, which were fedconcentrates with an equal crude protein level of145.0g/d and four digestible energy levels of12.5、14.0、15.6and17.1MJ/d, respectively, and the experiment lasted for58d(including10d foradaptation). Three ewes in each group were selected for a seven-day digestive metabolism test(allthe feces and urine collected) in the middle of the experiment. Two ewes selected from each groupwere slaughtered at the end of the experiment.The results showed as follows:(1) The digestibility and metabolic rate of gross energy for ewes in four groups increasedwith the increasing energy intake but differences among the experiment groups were notsignificant(P>0.05) and the average digestibility and metabolic rate of gross energy for latepregnant ewes were60.06%±2.92and50.09%±3.27respectively.(2) Average daily gain of early pregnant ewes increased significantly with the increasingGE、DE and ME intake in the condition of the same protein intake which met the normalgrowth needs (P<0.05).(3)The requirement of shanbei white cashmere goats for DE and ME of early pregnantewes can be estimated by the fomula as follows: DE（MJ/d）=0.5070W0.75+0.0329ADG（P=0.001，R~2=0.9938）�'�ME（MJ/d）=0.4130W0.75+0.0286ADG（P=0.002，R~2=0.9965），or DE（MJ/d）=0.5070W0.75+0.0263ADG1+0.0396ADG2（P=0.018，R~2=0.9482）and ME（MJ/d）=0.4130W0.75+0.0245ADG1+0.0327ADG2（P=0.010，R~2=0.9694).(4)In this experiment condition, the appropriate quantity of energy in diet for late pregnantewes were adding extra5.62MJ/d DE or4.89MJ/d ME on the basis of energy maintainrequirement for nonpregnant ewes, and in normal production conditions, the appropriate levels ofDE and ME were10.68~11.06MJ/kg and8.93~9.21MJ/kg(air dry basis) respectively.