羊子的 litter 尺寸和羔羊的出生体重:影响羔羊的健康,性能和尸体特征
1Dr. Joyce Van Donkersgoed Inc., Coaldale, Alberta T1M 1M3.
概括
选择具有较大 litter 尺寸的羊品种可以降低羊羔出生体重和生长性能,同时增加死亡率. 这影响了绵羊生产的整体效率.
科学领域:
- 动物科学动物科学
- 生殖生物学 生殖生物学
- 农业经济学 农业经济学
背景情况:
- 商业绵羊业务的目标是每年最大限度地提高每只母羊的羊肉产量.
- 提高母羊繁殖率的选择是实现这一目标的共同策略.
研究的目的:
- 为了研究选择更大的子大小对在商业绵羊环境中的羔羊出生体重,健康和表现的影响.
主要方法:
- 一个大型商业绵羊场的数据的回顾性分析.
- 在两个疫苗试验中收集的数据,包括羔羊的健康状况,表现和尸体特征.
- 统计分析母羊子大小,羊羔出生体重和后续结果之间的关联.
主要成果:
- 增加 litter 尺寸与减少羊羔出生体重显著相关.
- 较低的出生体重和较大的 litter 尺寸与较高的死亡率相关 (饥饿,肠炎).
- 较大的羔羊的生长性能下降和较差的尸体特征被观察到.
结论:
- 选择更高的母羊繁殖率可能会对羔羊的出生体重,生长和尸体质量产生负面影响.
- 增加的死亡率损失是选择非常大的 litter 尺寸的结果.
- 绵羊生产者和兽医应该仔细考虑这些权衡,以优化整体生产.
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