Study On Protein Requirement Of Shaanbei White Cashmere Goat In Non-pregnancy And Pregnancy

The confinedness of cashmere goats has been becoming urgent at present.Shanbei whitecashmere goats were chosen as experimental animals in this study.Feeding test, digestive metabolismtest and slaughter test were conducted to determine the proper energy requirements of Shanbeiwhite cashmere goats during non-pregnancy and late pregnancy respectively, in which twoindependent trials were included, in order to supply basic research data for the establishmentand improvement of feeding standards of Shanbei white cashmere goat.Test1. Study on protein requirement of nonpregnant Shaanbei white cashmere goatTwenty-four nonpregnant ewes in the second birth order which were not significantlydifferent in weight （P>0.05） were chosen to be randomly divided into four groups; During thefeeding trial period of sixty-six days, among which seven days were for preparative feeding,every group were fed the dietary with a DE level of7.98MJ/d, and the CP level of fourgroups were48.51g/d,55.92g/d,63.53g/d and68.14g/d respectively; Three ewes wereselected in each group to conduct the digestion and metabolism trial（collecting all the feces）of seven days in the middle of the test. The results showed as follows:（1） There was no significant difference in apparent crude protein digestion rate of fourdietaries for nonpregnant ewes（P>0.05）, and the average rate was65.54±0.43%;（2）The average daily gain of ewes in four groups increased along with the growing dailyintake of crude protein （CP）and digestible protein（DCP）, in a similar linear curve changes,and the correlation coefficient were0.9896and0.9825respectively for CP and DCP, and the4thgroup demonstrated the highest average daily gain, much higher than the first group （p<0.05）;（3） The regression equations between CP requirement and DCP requirement, metabolicweight(W^0.75) and daily weight gain（ADG）were as follows:CP（g/d）=2.2686W^0.75+0.4622ADG（P<0.01R²=0.9744）DCP（g/d）=1.4867W^0.75+0.3039ADG（P<0.01R²=0.9571）（4） The appropriate amounts of CP and DCP in daily ration（based on airing sample）were8.29%-10.43%and5.43%-6.83%respectively for the nonpregnant Shaanbei whitecashmere goat ewes.Test2. Study on Protein Requirement of Shaanbei White Cashmere Goat in pregnancy Twenty-three health pregnant ewes which were not significantly different in weight（P>0.05） and confirmed pregnant for90days were chosen as test object, among which threeewes were slaughtered for slaughter experiment at the beginning of feeding test, and the rest twenty eweswere for feeding test. Twenty ewes were randomly divided into four groups and every groupwere fed the dietary with a DE level of15.90MJ/d, and the CP level of four groups were91.45g/d,106.83g/d,120.21g/d and137.05g/d respectively, to conduct the feeding test of60days（8days for pre-experiment）; Three ewes were selected in each group to conduct thedigestion and metabolism trial（collecting all the feces） of fourteen days in the middle of thetest（the20th day） and two ewes which were about the average weight in each group werechosen to conduct the comparative slaughter experiment. The results showed:（1） The apparent CP digestion rate of ewes in four groups increased with the increase ofCP level, and the apparent CP digestion rate of different groups were59.54%、61.65%、62.86%and65.47%respectively, but the differences between groups were notsignificant（P>0.05）. The average apparent CP digestion rate of all ewes was62.38%±2.47.（2） The average daily gain of ewes in four groups increased with the increase of CP andDCP intake in the condition of the same digestible energy（15.90MJ/d） which met the normalgrowth needs, and the4th group demonstrated the highest average daily gain with162.31g/d,much higher than the first group with119.23g/d（p<0.05）;（3）The relations between requirements of CP and DCP, metabolic weight(W^0.75,kg)andaverage daily gain（ADG,g/d） for late pregnant Shaanbei White Cashmere Goat could bedescribed by the formula below:CP（g/d）=2.2686W^0.75+0.5371ADG（P<0.01，R²=0.9602）DCP（g/d）=1.4867W^0.75+0.3320ADG（P<0.01，R²=0.9599）orCP（g/d）=2.2686W^0.75+0.4622ADG1+0.6379ADG2（P<0.01，R²=0.8718）DCP（g/d）=1.4867W^0.75+0.3039ADG1+0.3679ADG2（P<0.01，R²=0.8111）；（4） In normal production conditions, the appropriate amounts of CP and DCP in dailyration for late pregnant ewes were adding extra75.81g/d CP or46.86g/d DCP on the basis ofprotein maintain requirement for non-pregnant ewes, and the appropriate amounts of CP andDCP in daily ration（based on airing sample） were10.12%and6.35%respectively;（5）Under condition of this study, the conversion efficiency of CP and DCP to pregnantproduct for Shaanbei White Cashmere Goat were18.06%and31.31%respectively.