RESPONSE TO METHIONINE SUPPLEMENTATION OF BROILER CHICKS FED PRACTICAL CORN-GROUNDNUT MEAL DIETS IN THE TROPICS

Two floor feeding trials, involving 1000 broiler chicks fed two different practical-type diets, were conducted in order to determine the methionine and total sulphur amino acid (TSAA) requirements of broiler chicks 0-6 weeks). Two protein levels (20 and 23%) each with an energy concentration of 2800 Kcal ME (kg diet and four supplemental methionine levels (0.1, 0.2, 0.3 and 0.4%) were tested. At the end of 6 - week feeding period, a common finisher ration was fed to 10 weeks of age. Under our experimental circumstances with dietshaving 23% protein and metabolizable energy of 2800 Kcal ME/kg diet and based on assumed methionine and cystine content of feeding stuff, the quantitative requirement for methionine of broiler chicks up to six weeks of age were about 0.53% diet which is equivalent to 2.3% of the dietary protein (or TSSA of 0.85 per cent diet, that is 3.7 per cent protein). Higher supplemental methionine at this protein and energy levels resulted in deterioration in liveweight gain and slight but non-significant improvement in feed/gain ratio. The rations containing 20% protein performed poorly relative to those containing 23%. Feeding of high quality common finisher rations neutralized the initial gains due to supplemental methionine within each protein levelbut did not offset the gains due to different dietary proteins.