Easy Feeding of Housed Sheep.

Abstract

In recent years sheep producers have emphasised the amount of labour required for managing sheep enterprises. In particular, the winter management of the flock during the past 25 years has been concentrated on silage, housing and associated labour inputs. One approach to reducing dependence on silage is the practice of extended grazing. On intensively stocked farms, however, the scope for this practice is limited. An alternative approach is the use of complete concentrate diets as substitutes for silage. A trial was conducted at the Knockbeg Sheep unit, Carlow for the purpose of examining the feasibility of feeding complete concentrate diets to ewes housed during late pregnancy and early lactation. A flock of ewes managed for lambing in January was divided into three groups at time of housing in November, each allocated to one of three diets: silage ad libitum plus concentrate supplements, a cereal-based loose mix concentrate or a pelleted concentrate diet. Levels of feeding offered in late pregnancy and early lactation were calculated to satisfy the energy requirements of 70 kg twin-bearing ewes. In addition to the dietary comparisons for ewes the resulting lamb crop provided the opportunity to compare two feeding systems for finishing, namely, early weaning onto grazed grass plus creep feed and early weaning onto a complete concentrate diet. Results on the components of ewe productivity, i.e. litter size, lamb survival rate and number of lambs reared, were similar on all three diets. Lamb birth weight was significantly heavier (0.4 to 0.6 kg) in the progeny of ewes offered the complete concentrate diets compared with the progeny of ewes offered silage. Nevertheless, the birth weight resulting from the ewes fed the silage diet was similar to results in previous years and, as a consequence, was considered satisfactory. Growth rate to 5 weeks of age in the progeny of the ewes offered the concentrate diets was relatively low due to an outbreak of pasteurellosis. Following recovery, compensatory growth was evident from 5 weeks to sale with the effect that the progeny of the three ewe diets were finished for slaughter at similar weights and ages. Ewes offered the complete concentrate diets increased significantly in liveweight and most of the increase was observed in ewes rearing singles. It is recommended that when feeding complete concentrate diets to ewes during late pregnancy and early lactation, single and twin bearing ewes should be accommodated separately and offered concentrate allowances appropriate to their requirements. Labour demand for feeding was highest on the silage diet and lowest for the pelleted formulation. Labour demand for feeding silage and concentrate supplements can be halved by using a pelleted concentrate diet. At 2001 prices the difference in costs between the silage and loose mix concentrate diets was small. When this factor is combined with reduced labour demand, it is considered that loose concentrate mixes offer an attractive alternative to silage feeding. There was no evidence in favour of early weaning of lambs onto grazed grass plus creep feed compared with the conventional system of early weaning indoor onto complete concentrate diets.