The rations differed in the proportion of concentrated feed in the ration and in the allowance of grazing in the summer. Three experimental groups (each with 8 sheep or goats) were kept in stables all year round. The ration contained 5, 20 or 40% concentrated feed (test groups S05, S20 and S40). A fourth experimental group was kept on pasture throughout the summer (feeding group W05, full pasture in summer, winter feeding same as S05 group). All animals received the same basic feed (mixture of grass silage, corn silage and hay) and the concentrate allocation was adjusted to the course of lactation. At least three lactations from each animal were examined, with one animal always receiving the same food throughout the entire experimental period.

The results of this experiment show that basal feed intake highest in the S05 and S20 groups in both animal species . Feeding high proportions of concentrated feed (40%) led to forage displacement. The basic feed intake of the grazing goats was particularly low. Total feed intake and live mass increased in both animal species as the proportion of concentrated feed increased and was also lowest in the pasture group. In both animal species, the animals in the S40 group had the highest milk production and the grazing animals had the lowest, with the grazing goats having a particularly sharp decline in milk production. The lactation performances of the S05 and S20 groups were intermediate and did not differ. High fat, protein and urea contents were found in the milk of grazing animals. With a high concentrate content, there was also a high protein content in the sheep's milk and a low fat content in the goat's milk.

Of particular interest in this experiment was efficiency , i.e. the amount of milk produced in relation to the resources used. The body mass efficiency, i.e. the milk production per kg of body mass, was highest in both animal species with high concentrate proportions. In terms of feed and energy efficiency, i.e. milk production per kg of dry matter consumed or per MJ of convertible energy consumed, the S05 group performed best. For the goats, the pasture group had by far the worst efficiency parameters. In conclusion, it can be said that high proportions of concentrated feed in the ration promote feed intake and milk production , but low proportions of concentrated feed are advantageous feed and energy efficiency .