Effects Of Dietary Crude Protein Levels On Growth Performance,Blood And Urine Physicochemical Indexes Of Liaoning Cashmere Goats Breeding Rams

In this study,hoggets of Liaoning Cashmere Goat with the same parity and body weight were selected as experimental subjects and were fed three experimental diets with crude protein levels of 10.5%,11.5%,and 12.5%.The effects of crude protein level in diets on growth performance,blood indexes and urine indexes of Liaoning cashmere goat hoggets were measured,which aims at exploring the reasonable dietary protein levels that can ensure the growth of Liaoning cashmere goats and prevent the occurrence of urolithiasis,and providing a theoretical basis for the promotion of high efficient home-breeding for Liaoning cashmere goats.The results of growth performance showed that the average feed intake of each experimental treatment group decreased with the increasing of crude protein level.The average daily feed intake:10.5% group>11.5% group>12.5% group,daily weight gain:11.5% group>12.5% group >10.5% group,the daily gain in the 11.5% group at the end of the test period was significantly higher than that in the other treatment groups(P<0.01),and the feed weight ratio in the 10.5% group was significantly higher than other treatment levels(P<0.01).The results of plasma indexes showed that the serum plasma calcium content decreased as the crude protein level increased,and the plasma phosphorus content increased first and then decreased as the crude protein level increased.At the end of the trial,serum calcium levels in the 12.5% group were significantly lower than that in the 11.5% group(P<0.01),and plasma phosphorus levels in the 12.5% group were significantly higher than in the 11.5% group(P<0.05).The plasma uric acid,creatinine,blood urea nitrogen and blood urea nitrogen/creatinine ration in the 12.5% group were significantly higher than those in other groups(P<0.01),and there was no significant difference in other groups(P>0.05);the total blood protein level of the 10.5% group was significantly lower than other groups in same condition(P<0.05);and the albumin content in the 11.5% group was significantly higher than that in the 12.5% group(P<0.05).The results of urine indexes showed that the urine pH in the 12.5% group was significantly higher than that in other groups(P<0.01),and the urine conductivity in the 12.5% group was significantly lower than that in other groups(P<0.05).).The urine calcium content and urinary phosphorus content in the 12.5% group were significantly higher than those in other groups(P<0.01);the uric acid level in the 12.5% group was significantly higher than other groups(P<0.01).Urinary creatinine was significantly higher in the 11.5% group than in other groups(P<0.05).On the other hand,the urea nitrogen content in the 12.5% group was significantly lower than that in other groups(P<0.01);12.5% urea nitrogen/creatinine was significantly higher than other treatment levels(P<0.05)and the urinary protein in 12.5% group was significantly higher than other experimental groups(P<0.01).The experimental results indicates that the crude protein level of 11.5% can increase the daily weight gain of hoggets of Liaoning cashmere goats,reduce the ratio of feed and weight,and stabilize the physiochemical indexes in blood and urine,which is beneficial to the normal growth of hoggets of Liaoning cashmere goats,which can effectively prevent the occurrence of urolithiasis.