宁夏地区斑点叉尾鮰工厂化繁育试验研究

Study on industrialized breeding of Ictalurus punctatus in Ningxia

为了探索斑点叉尾鮰在宁夏地区人工繁育技术的适宜条件,针对宁夏地区斑点叉尾鮰人工繁殖及苗种培育技术需求,分别开展了不同催产素配组及亲鱼人工配组的方法对斑点叉尾鮰催产率的影响、不同孵化温度对受精卵孵化率的影响及斑点叉尾鮰当年苗种培育试验。结果显示:水温23. 5℃条件下,使用催产药物可以使斑点叉尾鮰亲鱼在相对集中的时间段内产卵,且使用组合药物的催产率优于单纯使用一种药物的催产率,但是催产效果不明显。人工辅助配组产卵与池塘自然产卵相比,人工辅助配组产卵可以提高亲鱼的产卵率;斑点叉尾鮰受精卵最适人工孵化温度为24℃～26℃;适宜产卵温度为23℃～27℃。鱼种培育试验表明:斑点叉尾鮰在宁夏地区一龄鱼种生长比较快,从乌仔到一龄鱼种培育阶段建议放养密度在37. 5万尾/hm^2～45万尾/hm^2为宜。

In order to explore the suitable conditions for artificial breeding technology of Ictalurus punctatus in Ningxia,specific to technical requirements for artificial breeding and seed rearing,some experiments,for example,effects of different oxytocin combinations and artificial parent fish combinations on reproduction rate,hatching temperature on hatching rate of fertilized eggs and seed rearing experiment in that year of Ictalurus punctatus were carried out.The result showed that the use of oxytocic drugs enabled the Ictalurus punctatus to spawn in relatively concentrated time when the water temperature was 23.5℃,and the combination of drugs was better than the use of a single drug to spawn,but the effect was not obvious.Compared with natural spawning in ponds,artificial spawning could increase the spawning rate of parent fish,the optimum incubation temperature for fertilized eggs was 24℃-26℃,and the suitable spawning temperature was 23℃-27℃.Seed rearing experiment showed that the one-year-old seed grew fast,and from larva to one-year-old seed,the optimum stocking density of the Ictalurus punctatus was 375 000-450 000 fishes/hm 2 in Ningxia.