使用血统分析解释Saanen × Beetal山羊的遗传多样性和种群结构
Shweta Sahoo1, Rani Alex2, Vikas Vohra2
1Department of Animal Genetics and Breeding, ICAR-National Dairy Research Institute, Karnal, Haryana, India. drshwetasahoo@gmail.com.
Tropical animal health and production
|November 3, 2023
概括
对Saanen × Beetal山羊的血统分析显示,由于关闭的基因库,内生繁殖率高,遗传多样性低. 实施分层繁殖计划和引入新的血统对于管理这个有价值的杂交种群至关重要.
科学领域:
- 动物遗传学和动物繁殖
- 人口遗传学 人口遗传学
- 量化遗传学 量化遗传学
背景情况:
- 在卡纳尔州ICAR-NDRI的杂交种群Saanen × Beetal山羊已经维持了五十年.
- 这种生殖质适应热带气候,具有较高的牛奶产量和繁殖能力.
- 繁殖计划的有效管理需要了解遗传多样性和人口结构,以控制近亲繁殖.
研究的目的:
- 为了阐明Saanen × Beetal山羊群中的遗传多样性,种群结构和近亲繁殖水平.
- 评估一个封闭的核对遗传参数随着时间的推移的影响.
- 为优化育种策略提供见解,以保持遗传健康.
主要方法:
- 分析了2603只Saanen × Beetal山羊 (1971-2021) 的血统数据.
- 计算了关键的遗传参数,包括近亲繁殖系数,平均亲属关系和有效人口大小指标.
- 分析了一个参考队列 (2014-2017年出生) 来评估最近的人口动态.
主要成果:
- 完整血统的平均内生系数和平均亲属关系为4.20%和6.87%,在参考队列中增加到10.78%和10.80%.
- 少数祖先 (3) 对参考队列的基因库有显著的贡献,这表明瓶效应 (fe/fa = 2.14).
- 对大多数生殖特征来说,近亲繁殖是无意义的,除了第一次服务的年龄和第一次开玩笑的年龄.
结论:
- 封闭核的Saanen × Beetal山羊种群表现出显著的近亲繁殖和减少的遗传多样性,需要紧急的管理干预.
- 建议采用分层繁殖计划,重点是基于亲属关系的伴侣选择.
- 建议引入与 Saanen 和 Beetal 无关的交叉品,以减轻近亲繁殖的积累并增强遗传多样性.
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