The productivity of breeding ewes grazing on lucerne or grass and clover pastures on the tablelands of southern Australia. II. Wool production and ewe weight.

Author:

Donnelly JR,Morley FHW,McKinney GT

Abstract

Spring-lambing Merino and crossbred ewes grazing on dryland lucerne pastures were generally heavier throughout the year than ewes grazing on phalaris and subterranean clover pastures, even though they experienced greater weight losses during winter. These losses were mostly eliminated by compensatory gains in spring. Annual fleece weights of the Merino ewes grazing on lucerne or phalaris and subterranean clover pastures declined linearly by 146 and 64 g respectively for each additional ewe carried over a range of stocking rates from 9 to 18 ha-1. Corresponding figures for crossbred ewes were 114 and 46 g. In each case the difference between pasture species was significant (P < 0.02). Only at the lowest stocking rates were fleeces from ewes on lucerne heavier (by c. 500 g) than those from ewes on phalaris. At the highest stocking rates, there were no advantages in terms of wool production from grazing breeding ewes on lucerne. Not only was there a greater need for supplementary feed during late pregnancy to avoid losses from pregnancy toxaemia, but the lucerne pastures at all stocking rates proved more sensitive to unfavourable physical and chemical characteristics of soils than did phalaris and subterranean clover pastures. The fleece weights of Merino and crossbred ewes declined, on average, by 70 and 50 g per year for ewes aged between 1+ and 6+ years. Pregnancy reduced fleece weights by 5-10% in Merinos and 5-21% in crossbred ewes, depending on seasonal conditions which varied from year to year. For Merinos only, dry ewes grew about 4% more wool than lactating ewes. No other effects of reproduction on fleece weights were observed.

Publisher

CSIRO Publishing

Subject

General Agricultural and Biological Sciences

Cited by 10 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3