The Effect Of The Optimal Protein Levels Of Formula Feed On The Digestion And Metabolism Of Sika Calves

With the development of deer farming and the demand expansion of antler products, the intensification scale of rearing sika deer using mixed pellet dietaries, has taken initial shape, but the research was little about which are the optimal protein levels of formula feed for the growing sika deer calves. This experiment explored the optimal protein levels of formula feed for each growing period of sika deer calves and the effects on the digestion and metabolism.Eighteen young male sika deers were randomly selected and allocated into four groups, and were fed four different mixed pellet dietaries druing each growing period, respectively, to investigate the appropriate protein levels of formula feed in each growth peirod of sika calves. The conclusions were as follows: the optimum protein content of weaning sika calves from October to December was 14.66%; the sika calves over winter was 15.09%; the sika calves during early growing period was 14.26%; the one year old sika calves was 18.60%; and the sika calves during growing period was 19.47%.A 4×4 Latin Square experiment was designed; four young male sika deers were randomly selected and were fed four different dietary protein levels, to examine the effects of different dietary protein levels on the nutrient digestion and metabolism in both sika calves and growing deers, containing ten days of prepared feeding periods and five days of formal feeding period. The conclusions were as follows. The effects of diets with different protein levels on the concentration of serum urea nitrogen were significant (P<0.05), but other measurement indicators were insignificant (P>0.05). When the protein level in diet was 15.61%, the metabolic rate of protein for sika calves was 30.64%. The relationship between protein intake and sedimentable protein was: y1=0.394x1-27.568, R2=0.8828, n=8(P<0.05). The effects of diets with different protein levels on the intake and digestibilities of protein, P intak and the concentration of serum urea nitrogen were extremely significant (P<0.01), but other measurement indicators were insignificant (P>0.05). When the protein level in diet was 16.19%, the metabolic rate of protein for deer calves during growing period was 30.05%. The relationship between protein intake and sedimentable protein was: y1=0.3572x1-17.865, R2=0.969, n=8(P<0.05).The experiment results provided the basis for developing the standard of dietary protein levels of the sika calves during early growing period.