Now, we know from modern farming that if the level of breeding stock falls below about three hundred females, the future of species of locally is at risk.
现在，我们从现代农业得知，如果良种畜的水平低于300头雌性，那么当地的未来物种便岌岌可危。
Breeding stock
原声例句
剑桥雅思听力全真试题 6
BBC随身英语（官网版）
" On top of that, only if these studies are successful and the public are accepting, would we integrate these gene edits into commercial breeding stocks, " Dr Tait-Burkard told the BBC. So it seems we may have a while yet.
“最重要的是，只有当这些研究成功并且公众接受时， 我们才会将这些基因编辑整合到商业育种中， ” 泰特-伯卡德博士告诉 BBC。 所以看来我们可能还有一段时间。
经济学人 Science and technology
Horses with good results and a good pedigree are used as breeding stock for the next generation.
中文百科
人工选择 Selective breeding
（重定向自Breeding stock）
人工选择（英语：Artificial selection，又译人择）是指针对特定性状进行育种，使这些性状的表现逐渐强化，而人们不需要的性状则可能逐渐消匿的过程。最早对此进行定义的科学家为查尔斯·达尔文，他以发生在驯养动物的人择过程来阐述演化过程中的自然选择（或称天择）机制。
英语百科
Selective breeding 人工选择
（重定向自Breeding stock）
Selective breeding (also called artificial selection) is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits (characteristics) by choosing which typically animal or plant males and females will sexually reproduce and have offspring together. Domesticated animals are known as breeds, normally bred by a professional breeder, while domesticated plants are known as varieties, cultigens, or cultivars. Two purebred animals of different breeds produce a crossbreed, and crossbred plants are called hybrids. Flowers, vegetables and fruit-trees may be bred by amateurs and commercial or non-commercial professionals: major crops are usually the provenance of the professionals.