Egg weight and other production responses resulting from the supplementation of a semi‐purified layers' ration with energetically equivalent amounts of maize starch or maize oil

Equivalent levels of metabolisable energy (m.e.) from either maize starch or maize oil were fed to laying hens receiving a constant intake of all other nutrients from a semipurified, low‐fat diet. Maize oil supplementation significantly improved mean egg weight and total egg weight but had no significant effect on egg production compared with equivalent amounts of energy in the form of maize starch. The results indicated that a component of the oil other than m.e. was responsible for these improvements in production. Although in most instances the results confirmed those obtained previously when conventional diets were fed, certain differences in the responses to the two types of diet were evident. The production responses of birds fed a daily intake of 280 kcal m.e. were not significantly reduced in comparison with birds fed 325 kcal m.e. daily and the efficiency of utilisation of m.e. for egg production was substantially increased.