3种饵料对中华绒螯蟹卵巢发育和育肥效果的影响

Effects of Three Diets on Gonadal Development and Fattening of Adult Female Chinese Mitten Handed Crab,Eriocheir sinensis

测定和比较了硬颗粒饲料、膨化饲料和冰鱼的生化组成,在直径1.08m、高1m的500L循环水槽中进行了80d的养殖试验,比较了3种育肥饵料对体质量为65~90g的中华绒螯蟹雌蟹的育肥成活率、卵巢指数、肝胰腺指数、蟹壳、肝胰腺和卵巢色泽的影响。试验结果显示,冰鱼的粗蛋白、粗脂肪和灰分含量最高,膨化饲料的灰分含量最低,硬颗粒饲料的水分和粗脂肪含量最低;冰鱼的总氨基酸、必需氨基酸和非必需氨基酸含量明显高于两种饲料,硬颗粒饲料和膨化饲料的氨基酸组成接近;冰鱼的总饱和脂肪酸、C20:4n6、C20:5n3、C22:6n3和总高不饱和脂肪酸含量均最高,C18:2n6含量最低;膨化饲料总饱和脂肪酸和总单不饱和脂肪酸含量最低,但C18:2n6含量最高。冰鱼组和膨化饲料组雌蟹的最终成活率显著高于硬颗粒饲料组(P<0.05);育肥40d后,3个饵料组的卵巢指数无显著差异,80d后,膨化饲料组和冰鱼组的卵巢指数显著高于硬颗粒组(P<0.05)。膨化饲料组蟹壳和卵巢的红度显著高于硬颗粒饲料组,冰鱼组的肝胰腺亮度和黄度最高,但红度显著低于硬颗粒饲料组和膨化饲料组。综上所述,优质膨化饲料的综合育肥效果优于冰鱼,特别是卵巢红度;与传统的硬颗粒饲料相比,优质膨化饲料可以显著提高育肥成活率,促进卵巢发育,提高蟹壳和卵巢的红度。

The biochemical compositions of hard pelleted feed,extruded feed and frozen trash fish were analyzed,and survival,gonado-somatic index(GSI),hepato-somatic index(HSI),and coloration of ovary were compared in fattened adult female Chinese mitten handed crab Eriocheir sinensis with body weight of(65~90)g reared in a 500L circulating tank with a diameter of 1.08 m and height of 1 m and fed the three diets above for 80 d.The results showed the frozen trash fish contained the maximal contents of crude protein,crude lipid and ash,the extruded feed contained the minimal ash content,and the hard pellet feed contained the minimal moisture and crude lipid content.There were higher contents of total amino acid(TAA),essential amino acid(EAA)and nonessential amino acid(NEAA)in frozen trash fish than those in the other two feeds,with similar amino acid composition in both hard pelleted and extruded feeds.Frozen trash fish contained the maximal∑SFA(saturated fatty acid),C20:4n6,C20:5n3,C22:6n3 and∑HUFA(high unsaturated fatty acid)contents,and the minimal C18:2n6 content.The extruded pellet feed contained the minimal∑SFA and∑MUFA(monounsaturated fatty acid)contents,and the maximal C18:2n6 content.There was significantly higher survival rate in fattened adult female Chinese mitten handed crab fed frozen trash fish and the extruded diet than that in fattened adult female crab fed the hard pelleted diet(P<0.05).No significant difference in GSI was observed in the crab fattened with the three diets in 40 days,and there was significantly higher GSI in fattened crabs with extruded pelleted diet and frozen fishes than in fattened crab with hard pelleted diet in 80 days(P<0.05).The significantly higher redness(a*)in shell and ovary were found in the fattened crab fed extruded diet than that in the fattened crab fed hard pelleted diet(P<0.05),with the maximal lighteness(L*)and yellowness(b*),in the fattened crab with frozen trash fish,and significantly lower redness than those in the fattened crab with hard pelleted diet and the extruded diet(P<0.05).In comprehensive fattening effects,especially in redness of ovary,high quality extruded diet showed better than frozen trash fish,and led to improve the survival rate of fattening,ovarian development,and redness of shell and ovary of adult female Chinese mitten handed crab.