DETERMINATION OF OPTIMUM THREONINE REQUIREMENTS OF JAPANESE QUAIL (Coturnix coturnix japonica) CHICKS REARED UNDER TROPICAL ENVIRONMENT

Abstract

Threonine, like most amino acids, is traditionally noted for its role in protein synthesis. However, dietary threonine concentration required for the maximum performance of Japanese quails is yet to be determined, therefore, a study was conducted to determine the optimum threonine requirement of Japanese quail chicks in the tropical environment. A total of four hundred and fifty, two weeks old quail chicks (mixed sexes) were randomly allocated to five dietary treatments (0.67, 0.81, 0.95, 1.08 and 1.22 % total threonine) and replicated thrice in a completely randomized design (CRD). There were no significant differences (P>0.05) in average weight gain, average feed intake, feed conversion ratio and age at first lay of quails fed the dietary treatments. Weight of first egg laid was significantly (P<0.05) higher for birds fed 1.08% total threonine diets than those fed other dietary treatments. Live weight, dressed weight, dressing percent, thigh, heart and gizzard weights were statistically (P>0.05) similar for all treatments. There were significant differences (P<0.05) in haematological parameters and serum indices studied except white blood cell, total protein, monocyte, eosinophils, mean corpuscular volume, alanine amino transferase, alkaline phosphatase (P>0.05). It was concluded that the performance of birds were not influenced by the dietary treatments up to the highest dietary level of threonine studied (1.22%). Therefore, it is possible that the optimum dietary level of threonine may be above 1.22 %. Further studies will be necessary to establish higher doses of dietary threonine requirement of Japanese quails reared under tropical climatic environment.