专用微胶囊饲料驯养培育兰州鲇稚幼鱼效果研究

Microencapsulated Forage for Silurus lanzhouensis Larvae and Juvenile Aquaculture

【目的】为解决兰州鲇(Silurus lanzhouensis)产业发展中面临的仔稚鱼培育饵料制约问题,开展微囊饲料对兰州鲇仔稚鱼驯食转化、生长发育和酶活性的影响研究。【方法】首先将驯养培育兰州鲇稚鱼分为微囊饲料组(WW)、微囊饲料+水丝蚓组(WL)及水丝蚓(Limnodrilus)组(LL)3个处理组,进行为期30 d的驯养培育稚鱼试验,通过记录稚鱼死亡数量、测量体重、体长等生长指标,探讨微囊饲料对兰州鲇稚鱼存活、生长的影响;以此为基础开展为期115 d微囊饲料(WW)与肉糜(RR)2个处理组驯养兰州鲇幼鱼试验,通过测定试验幼鱼体重、体长等生长指标,以及消化系统不同组织中脂肪酶、淀粉酶及胃蛋白酶活性,探讨微囊饲料对兰州鲇幼鱼生长、代谢的影响。【结果】(1)微囊饲料培育兰州鲇稚鱼,驯食转化率不及水丝蚓,但成活率最高,达(94.3±0.9)%,且与其余两组差异显著(P<0.05),微囊饲料+水丝蚓组(WL)仔鲇体重增长最快(P<0.05);水丝蚓组(LL)组仔鲇体重特定生长率(SGR)和绝对生长率(AGR)均显著低于微囊饲料组(WW)组和微囊饲料+水丝蚓组(WL)组。(2)微囊饲料培育兰州鲇幼鱼,可显著促进生长,且组间差异显著(P<0.05);除中肠、后肠和胃组织中胃蛋白酶活性组间差异不显著外,投喂微囊饲料组的其他组织中的脂肪酶、淀粉酶及胃蛋白酶活性均显著高于投喂鱼糜组的(P<0.05)。【结论】微囊饲料可促进兰州鲇稚幼鱼生长发育,且规格较为整齐。因此,微囊饲料在兰州鲇养殖产业发展中具有重要的应用价值,进一步研究并推广将对兰州鲇养殖产业发展发挥重要支撑作用。

【Objective】A microencapsulated forage was evaluated to replace live worms for feeding at early development stage of the carnivorous Lanzhou catfish(Silurus lanzhouensis Chen)based on the resulting larval weaning,juvenile growth,and enzyme activities in digestive tracts.【Method】Two experiments were conducted with the microencapsulated forage(MF)introduced to the fish at different ages.In the first experiment,3 groups of randomly divided catfish larvae were fed with either MF(WW),a combination of MF and live worms(WL)or live preys(LL).Larval survive rate and growth in 30 d were monitored following the feeding.The second experiment examined the effects of WW versus minced meat(RR)for feed on the growth and metabolism of the juveniles for 115 d.【Result】(1)Domesticating the fish in the WW group was significantly the least effective among all.However,the survival rate of(94.3±0.9)%on the fish fed with WW was significantly higher than the other two forages(P<0.05).And the body weight increase of the catfish in the WL group were the fastest(P<0.05).Significant differences in SGR and AGR of LL group were observed compared with the other two treatments(P<0.05).(2)MF appeared to significantly promote the growth from larval to juvenile stage of the catfish.There were significant differences on the performances by the different forages(P<0.05).Except for no difference between 2 treatments for the enzymatic activities of pepsin in the midgut,hindgut and stomach,the enzymatic activities of lipase,amylase,and pepsin in the pancreas,stomach,foregut,midgut,and hindgut of the fish tended to be higher in the WW group fed on WF than on RR.【Conclusion】MF significantly improved the growth and maintain a relatively uniform size of catfish at early development stages.The use of MF for catfish aquaculture was highly recommended.