不同配比南极磷虾粉饲料对网箱养殖俄罗斯鲟生长及氟累积的影响

Effects of krill meal on growth performance and fluoride accumulation of cage cultured Acipenser gueldenstaedtii

配制南极磷虾粉替代饲料中鱼粉比例分别为0%、10%、20%、30%的4组饲料饲喂俄罗斯鲟(Acipenser gueldenstaedtii)200 d后,分析南极磷虾粉替代部分鱼粉对网箱养殖俄罗斯鲟生长和鱼体组织氟残留的影响。结果表明:(1)随着南极磷虾粉替代比例的升高,俄罗斯鲟的末重、增重、特定生长率、蛋白质效率先上升后下降,饲料系数先降低后升高,10%组显著高于对照组和其它试验组(P<0.05);(2)实验结束时,俄罗斯鲟肌肉、肝脏和鱼鳔的氟浓度低于检测限,但鳃、皮、脊骨和背骨呈现剂量浓度效应,各试验组较对照组显著升高(P<0.05)。综上所述,在本实验条件下,在俄罗斯鲟饲料中加入10%比例的南极磷虾粉时获得最佳生长效果和较低的组织氟累积。

Russian sturgeon,Acipenser gueldenstaedtii,has recently received great attention in China as a promising commercial freshwater species for its ＇high value. Commercial diets for this species have been traditionally based on fish meal（ FM） and fish oil. However,the limited supply has hindered the rapid development in aquaculture industry. A significant challenge is to increase the amount of alternative protein sources in feed without compromising the growth of cultured fish. The krill has become a hot topic in fishery recently. To date,krill is available commercially mainly in the form of krill meal. Krill meal is an attractive ingredient for aquaculture industry because of its＇ palatability,balanced amino acids profile and as excellent sources of essential fatty acids,minerals and functional components such as nucleotides and small peptides.In addition,an enhancement of growth on fish species have been reported when fed with diets containing krill meal. These results all suggested that krill meal may improve the growth performance of sturgeons fed by krillmeal-included diets. In the present study,a 200-day feeding trial was conducted to evaluate the effects of krill meal on growth performance and fluoride accumulation of cage-cultured Russian sturgeon. Four extruded diets in which KM replaced 0%,10%,20%,or 30% of fish meal in the formulation were fed to duplicate groups of（ 4. 05 ± 0. 19） kg sturgeon. The growth trial was conducted in net cages in a commercial sturgeon farm in Hangzhou under natural photoperiod. Experimental results showed that final body weight（ FBW）,weight gain（ WG）,specific growth rate（ SGR）,and protein efficiency ratio（ PER） for Russian sturgeon first increased and then decreased while feed conversion ratio（ FCR） first decreased and then increased and 10%group was significantly higher than that of the control and other groups（ P〈0. 05）. Meanwhile,the fluoride concentrations in the dorsal muscle,liver,as well as swim bladder in all dietary groups were below detectable limits. In the gills,skin,vertebral bone and dorsal scutes,the fluoride contents from the KM groups progressively increased with the rising of fluoride concentrations in diets（ P〈0. 05）. In conclusion,KM can be included at a level of 10% in the diets of Russian sturgeon with the best growth performance.