A 'protein bank' of Lotus uliginosus cv. Maku as an alternative to conventional protein supplements for weaned lambs grazing on natural pastures during summer and autumn

摘要

The aim of this study was to evaluate the use of restricted grazing of an improved natural pasture as an alternative to conventional protein supplements for weaned lambs grazing natural pastures during summer-autumn. Two natural pastures that differed in dry matter allowances were used as basal diets. Sixty Corriedale lambs, 3 months old, were divided into 10 homogeneous groups. For each natural pasture, one group of lambs was randomly assigned to one of the following treatments (at 10 lambs/ha): continuous grazing (control); control + protein block (150 g/lamb. day); control + soybean meal (100 g/lamb. day); control + supplemental protein obtained from grazing for 3 h/day a natural pasture improved with Lotus uliginosus cv. Maku; or same as previous, except that grazing was allowed 1 in 3 days. Performance results (final bodyweight, average daily gain, and difference between initial and final body scores) were analysed as a completely randomised block design with subsampling. Lambs grazing 3 h/day or 1 in 3 days on improved pasture or supplemented with soybean meal showed better (P < 0.05) performance than non-supplemented lambs. Lambs consuming the protein block performed similarly (P > 0.05) to control lambs. The experiment demonstrated that feeding strategies using controlled grazing of natural pastures improved with lotus Maku or soybean meal supplementation are effective to achieve target growth rates of weaned lambs grazing natural pastures in summer-autumn.