Grazing management and supplementation for the lowland sheep flock
| العنوان: | Grazing management and supplementation for the lowland sheep flock |
|---|---|
| المؤلفون: | T. T. Treacher |
| المصدر: | BSAP Occasional Publication. 14:45-54 |
| بيانات النشر: | Cambridge University Press (CUP), 1990. |
| سنة النشر: | 1990 |
| مصطلحات موضوعية: | Stocking rate, Polymers and Plastics, Agronomy, Grazing, Domestic sheep reproduction, Weaning, Growing season, Flock, Biology, N fertilizer, Sheep flock |
| الوصف: | Stocking rate is the major determinant of differences in profitability of recorded sheep flocks. Detailed guidelines, based on sward height profiles, for the management of continuously grazed sheep pastures were published in the mid 1980s. The key recommendation of these guidelines was maintenance of a sward height of about 6 cm from April to mid June. It arose from experimentation showing that, at this height, herbage intake by lactating ewes is nearly maximal, the level of herbage utilization was satisfactory and a good sward structure was achieved.The paper reviews recent studies, which suggest modifications to the original management recommendations. Although concentrate supplementation of ewes in the spring, until the sward reached 4 cm, was recommended in the guidelines, there is little evidence of a response in lamb weight at weaning to supplementation unless swards are below 3 cm, which rarely occurs for long in lowland conditions. Decision rules for adjustment of the grazing area to achieve the height guidelines still present some problems, particularly in Scotland, where the growing season is short. An increase in sward height from 6 to 8 cm may be necessary from mid June to maintain high growth rates in lambs and prevent very low growth rates in weaned lambs. Rapid declines in sward height prior to mating may result in intakes below maintenance, which reduce lambing percentage, although this can be prevented by supplementation.Mixed swards of white clover and grass with zero or low N fertilizer input give outputs of lamb production per ha that are 75 to 100% of the output from swards receiving high N fertilizer inputs. Guidelines for management of mixed swards are essentially the same as for pure grass swards. |
| تدمد: | 2053-5953 0263-967X |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_________::db506ab8860f404d360a3e79bbab5d72Test https://doi.org/10.1017/s0263967x00002044Test |
| حقوق: | CLOSED |
| رقم الانضمام: | edsair.doi...........db506ab8860f404d360a3e79bbab5d72 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 20535953 0263967X |
|---|