Amino acid requirements of South African Mutton Merino lambs 3. Duodenal and whole empty body essential amino acid profile
The duodenal and whole empty body essential amino acid (EAA) profile of South African Mutton Merino lambs fed a standard growth diet was investigated. The data of 20 lambs were used. With the exception of phenylalanine, significant (p < 0.05) differences between the EAA concentrations of the duodenal digesta and whole empty body occurred. From the chemical score, it was concluded that the duodenal digesta was first-limiting in histidine and second-limiting in methionine, followed by threonine and arginine for the whole empty body growth of South African Mutton Merino ram lambs fed a standard diet high in rumen degradable protein. A calculated essential amino acid composition for the correction of imbalances in duodenal digesta was as follows (%): 11.21 arginine; 14.53 histidine; 8.17 isoleucine; 9.97 leucine; 8.64 lysine; 13.87 methionine; 9.97 phenylalanine; 12.54 threonine and 11.11 valine.