鳜春季、夏季和秋季按季节人工繁育模式的研究

STUDY ON ARTIFICIAL PROPAGATION MODES OF MANDARINFISH(SINIERCA CHUATSI) IN SPRING, SUMMER AND AUTUMN BY SEASONS

为满足不同地区、不同季节鳜(Sinierca chuatsi)养殖需要,实现均衡上市的苗种供应要求,研究通过对两批亲鱼在不同季节各进行4次交替人工催产,按月建立苗种繁育模式。结果显示,池塘中自然培育的亲鱼,卵巢成熟系数出现2个峰值,而网箱中培育的亲鱼,经过4次人工催产,出现4个成熟系数峰值,产卵量和出苗量与成熟系数峰值正相关。以二繁的成熟系数、产卵量和出苗量最高,显著高于其他三次(P<0.05),二繁、三繁和四繁的受精率、孵化率和苗种培育成活率均较高,显著高于一繁(P<0.05),温度是影响一繁受精率、孵化率和苗种培育成活率的主要因素。产后亲鱼成活率随人工繁殖次数增加而下降,其中以一繁的成活率最高,达93.33%,显著高于三繁和四繁(P<0.05)。综上结果表明,通过按季节分梯次人工繁育模式解决鳜苗种生产的均衡供应是可行的。这为转变鳜的养殖方式提供了科学依据,也为其他鱼类苗种的均衡生产提供了借鉴意义。

In order to meet the demands of mandarin fish culture in different regions and seasons,and to achieve the requirement of fingerling supply of a balanced marketing,in this study,two batches broodstock were alternate artificial induced for 4 times in different seasons,and established a seed breeding mode of fry and fingerling breeding by month.The results showed there were 4 peaks of gonadasomatic index for broodstock cultivated in the cage after 4 times of artificial spawning,while broodstock naturally cultivated in pond showed only 2 peaks of gonadasomatic index.The total spawning eggs and hatching fry quantity of artificial propagation were positively correlated with the peak of gonadasomatic index.The gonadasomatic index,total spawning eggs and hatching fry quantity of second artificial propagation were the highest,which were significantly higher than the other three times(P<0.05).The fertilization rate,incubation rate,fry and fingerling survival rates in of the second,third and fourth propagation were significantly higher than those in first propagation(P<0.05).The temperature was the main factor affecting fertilization rate,incubation rate,fry and fingerling culture survival rate.The survival rate of induced broodstock decreased with the increaseding artificial propagation frequency.The survival rate of first propagation was up to 93.33%,significantly higher than that of third and fourth propagation(P<0.05).To sum up,it was feasible to solve the balanced supply of fingerling in mandarin fish by the modes of artificial breeding by seasonal echelon.This provides a scientific basis for changing culture mode of mandarin fish,and also has important referential significance for balanced supply of fingerling in other species.In summary,the results show that it is feasible to solve the balanced supply of seedling production by the artificial breeding mode according to the seasons.This provides a scientific basis for the changing culture mode of mandarin fish,and also provides a reference for the balanced production of other fish species.