关于繁殖母猪群体更新率的探讨

Exploring the replacement rate of breedingsow herd

母猪群体的年更新率,其实是“母猪利用年限”问题,也是为了达到目标PSY水平所需合理的胎龄结构的生物经济学问题。影响更新率或母猪利用年限的因素有遗传因素,更多的是非遗传因素。主要原因是,母猪利用年限无法在核心群度量,也无法直接纳入综合选择指数,遗传力低,为0.05~0.25。因而,后备母猪培育选留标准、饲喂体况管理、繁殖管理是世界养猪发达国家公认的母猪利用年限的主要提高手段。遗传选择和选择肢蹄完整良好的母猪是提高母猪利用年限的间接选育法,十分重要。

The annual repcacement rate of the sow population is actually a problem of“lifespan of the sow”as well a bioeconomic problem of the appropriate parity structure needed to achieve the targeted PSY level.The impact factors that affect the renewal rate or the longevity of sows have genetic factors,and more are non-genetic factors.The main reason is that the lifespan of sows cannot be measured within nucleus herd,nor can it be directly included in the complex selection index,along with the low heritability from 0.05 to 0.25.Therefore,the major measures for improving sow longevity or reducing the replacement rate are gilt development and selection standards,feeding management on body condition,reproductive management,which are recognized by developed countries with high level pig production.Genetic selection and selection of sows with integrity of legs and hooves are important indirect selection methods for improving the longevity of sows.