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鱼种是发展淡水养鱼的物质基础,没有好的,足够数量的鱼种是难以获得养殖高产的。几年来,我们提倡的推广“大规格”鱼种,其目的就在于此。而且必将或正在生产中发挥积极作用。但实际上在鱼种生产中有待研究探讨的问题,远非仅仅是“大规格”鱼种一个问题。而且即使在已往开展的“大规格”鱼种上问题也不少。诸如到现在为止,年生产“大规格”鱼种的比重到底占多少?品种有哪些?为什么发展不快?究竟多大标准才够得上是大规格鱼种?按目前现有的鱼种生产体制的前景如何?等。总之,所有上述问题的解决快慢和解决程度都将直接影响到养殖生产的发展速度和单产的提高。
Fish species are the material basis for the development of freshwater fish farming. It is difficult to obtain high-yielding stocks without a good enough number of fish species. In the past few years, we advocated the promotion of “large size” fingerlings, and its purpose lies in this. And will or is in production to play an active role. However, in fact, the problems to be studied and studied in the production of fish species are far more than just a problem for species of “large size”. And even in the past to carry out the “big size” species on the lot of problems. For example, up to now, what is the proportion of the annual production of “large size” fingerlings? What are the varieties? Why is it unpleasant? How many standards are enough for large size fingerlings? According to the existing species production system How about the prospects? In conclusion, the speed of solution and the resolution of all the above problems will directly affect the rate of development of breeding and the improvement of yield.