AgroParisTech, UMR 1313 Génétique Animale et Biologie Intégrative, 16 rue Claude Bernard, 75231 Paris 05, France.
Genet Sel Evol. 2011 Nov 2;43(1):36. doi: 10.1186/1297-9686-43-36.
High selection pressure on domestic cattle has led to an undesirable increase in inbreeding, as well as to the deterioration of some functional traits which are indirectly selected. Semen stored in a cryobank may be a useful way to redirect selection or limit the loss of genetic diversity in a selected breed. The purpose of this study was to analyse the efficiency of current cryobank sampling methods, by investigating the benefits of using cryopreserved semen in a selection scheme several generations after the semen was collected.
The theoretical impact of using cryopreserved semen in a selection scheme of a dairy cattle breed was investigated by simulating various scenarios involving two negatively correlated traits and a change in genetic variability of the breed.
Our results indicate that using cryopreserved semen to redirect selection will have an impact on negatively selected traits only if it is combined with major changes in selection objectives or practices. If the purpose is to increase genetic diversity in the breed, it can be a viable option.
Using cryopreserved semen to redirect selection or to improve genetic diversity should be carried out with caution, by considering the pros and cons of prospective changes in genetic diversity and the value of the selected traits. However, the use of genomic information should lead to more interesting perspectives to choose which animals to store in a cryobank and to increase the value of cryobank collections for selected breeds.
国内牛种的高度选择压力导致了近交程度的不可取增加，以及一些间接选择的功能特征的恶化。储存在低温库中的精液可能是一种有用的方法，可以重新引导选择或限制选定品种中遗传多样性的丧失。本研究的目的是通过调查在收集精液后的几代中使用冷冻精液在选择方案中的益处，分析当前低温库采样方法的效率。
通过模拟涉及两个负相关特征和品种遗传变异性变化的各种情况，研究了在奶牛品种的选择方案中使用冷冻精液的理论影响。
我们的结果表明，只有在选择目标或实践发生重大变化的情况下，使用冷冻精液来重新引导选择才会对负选择特征产生影响。如果目的是增加品种的遗传多样性，那么这可能是一个可行的选择。
使用冷冻精液来重新引导选择或提高遗传多样性，应谨慎考虑潜在遗传多样性变化的利弊以及选定特征的价值。然而，利用基因组信息应该会为选择要存储在低温库中的动物以及增加选定品种的低温库收集物的价值提供更有趣的视角。
