Methionine supplementation of practical broiler rations

Synopsis

Four trials, involving 2170 five‐week‐old broilers fed 5 different practical‐type diets, were conducted in order to determine the total sulphur amino acid (SAA) requirement of broilers during their finishing period (5 to 10 weeks of age).

No differences were found between the SAA requirements for the 5–8 week and 5–10 week periods, nor between those of male and female broilers. The requirements can be summarised as 3.5 and 3.6 per cent SAA, on the basis of dietary protein, for maximal weight gain and optimal food efficiency, respectively. It seems, therefore, that the SAA requirement does not change with age when it is expressed in terms of dietary protein, although the level of the latter is reduced when changing from starter to finisher diets. The SAA requirement of 3.6 per cent of the protein corresponds to about 0.66 per cent of the diet, to 0.31 and 0.21 per cent per megacalorie (therm) of productive and metabolisable energy, respectively, per kg. diet, and to 16.5 and 18.4 mg. SAA per gram weight gain during the 5–8 and 5–10 week periods, respectively.

Different performances of chicks up to 5 weeks of age may seriously confound the results of dietary treatments applied during the finishing period.

Notes

Contribution from the National and University Institute of Agriculture, Rehovot, Israel. 1966 Series, No. 991‐E.