The relationship between yield of milk solids of dairy cows and response to change in plane of nutrition

SUMMARY A study is reported of the effect of initial potential for milk production of individual cows on the change in milk output consequent upon a change in amount of feed allowed per day. In this study equal initial rations and equal changes in ration were imposed on all cows. The main conclusion was that the greater the initial yield of milk, of milk fat, of solids-not-fat (SNF) or the SNF content of the milk of a cow the greater was the effect of a change in feed allowance on that attribute. It is argued that the effects are large enough to warrant consideration in practical feeding systems.