Experiments on the use of home-grown foods for milk production: I. The effect of war-time changes in the food supply on the nutrient intake and milk production of dairy cows

1. An experiment has been conducted with dairy cows to find the effect on milk production of feeding rations with a high dry-matter content—typical war-time rations.

2. It was found that where a ration high in dry matter is fed, the cow tends to refuse food, and a statistically significant fall in milk production results. The correlation between the refusal of food, calculated in terms of starch equivalent, and the fall in milk production was 0·959.

3. The factors causing this inability of the cow to consume sufficient food to meet her total nutrient requirements have been considered. It has been concluded that dry-matter consumption is not an adequate method of expressing the amount of food a cow will consume, and that the major factor influencing food consumption is the palatability of the individual foods making up the ration.

My thanks are due to Dr S. J. Rowland for chemical analysis of the individual foods used in the experiments.