Feeding levels during the growing phase affect the production of primiparous Finnish Landrace ewes

Abstract

The effect of different feeding levels on the performance of primiparous ewes was studied in 31 Finnish Landrace ewes bred to lamb at the age of one year. Ewe lambs, initially weighing on average 19.2 kg (SEM 0.63), were placed on a low (L), standard (S) or high (H) level of feeding from 2 months of age to the end of mating and from 2 months pre-partum to the end of 8-week lactation. Changes in live weight were affected by the diet. During rearing, the ewe lambs on L diet gained significantly less (18.0 vs. 24.1 kg/lamb, P<0.0001) and they were also significantly lighter at mating than those on H diet (47.8 vs. 54.1 kg/lamb, P<0.01). Excluding ewe lambs on L diet, mating was successful. The highest litter size (4 lambs/ewe) occurred on H diet. Intensive feeding did not have a negative effect on milk yield. Ewes on S diet tended to produce the most milk, but the differences between diets were not significant. A high feeding level decreased the fat content, but its influence on the protein content of milk was small. It was suggested that replacement ewe lambs can be reared together with market lambs. The official Finnish feeding recommendations for sheep seemed to be unnecessarily high.