Requirement of the hen for sulphur-containing amino acids.

The sulphur amino acid requirements of White Leghorn-type laying hens were determined in two 52-week experiments using diets based on maize and soyabean meal providing from 5.0 to 6.5 g sulphur amino acids/kg, 12.35 MJ ME/kg and 8.6 to 8.8 g lysine/kg. There were six replicates of 15 individually-caged hens each per treatment. 2. A requirement of approximately 775 to 800 mg sulphur amino acids/hen d, of which about 390 to 440 mg was methionine, was found for a maximum of 80 to 83 eggs/100 hen d. There were indications that the requirement for maximum egg production was less than that for maximum efficiency of food utilisation. 3. Diets containing 138 g protein/kg supplemented with methionine and lysine supported production and food utilisation as effectively as a diet containing 167 g protein/kg.