五种诱食剂对中华绒螯蟹诱食效果的研究

为提高配合饲料诱食性、减少饲料溶失, 试验以均重为(26.4±0.17) g的中华绒螯蟹(Eriocher sinensis)为研究对象, 尝试用色素指示法筛选出其适用诱食剂。首先, 在基础日粮中分别添加4种不同颜色的食用色素, 每种颜色饲料取相同颗粒数放入同一养殖箱内, 观察饲料颜色对中华绒螯蟹摄食有无影响; 然后, 以基础日粮为对照, 鱿鱼膏(Squid extract, SE)、酵母核苷酸(Yeast hydrolysate, YH)、棉粕酶解肽(Cottonseed meal proteinhydrolysate, CPH)、甜菜碱(Betaine)以及大蒜素(Allicin)5种诱食剂分别设置4个浓度梯度, 同种诱食剂不同浓度的饲料添加不同颜色的食用色素, 每种颜色饲料取相同颗粒数放入同一养殖箱内, 筛选出每种诱食剂最适浓度; 之后, 选用5种诱食剂的最适浓度, 采用同样方法, 比较其诱食效果。结果显示: (1)不同颜色的基础日粮对中华绒螯蟹摄食无显著影响(P>0.05); (2)添加0.3%鱿鱼膏组、0.6%酵母核苷酸组、0.6%棉粕酶解肽组以及0.09%大蒜素组的诱食指数最高, 且显著高于对照组(P<0.05); 添加1%甜菜碱组诱食指数最高, 但与对照组相比无显著差异(P>0.05); (3)添加0.6%棉粕酶解肽组的诱食指数显著高于除0.6%酵母核苷酸组外的其他各组(P<0.05), 高于酵母核苷酸组但差异不显著; 0.3%鱿鱼膏组诱食指数略高于0.09%大蒜素组显著高于1%甜菜碱组(P<0.05)。结果表明: 饲料颜色对中华绒螯蟹摄食无影响; 鱿鱼膏、酵母核苷酸、棉粕酶解肽、甜菜碱和大蒜素的最适浓度依次为: 0.3%、0.6%、0.6%、1%和0.09%, 其诱食性为: 棉粕酶解肽>酵母核苷酸>鱿鱼膏>大蒜素>甜菜碱。其中, 0.6%棉粕酶解肽或0.6%酵母核苷酸诱食效果较好, 建议作为中华绒螯蟹诱食剂使用。

Effects OF FIVE ATTRACTANTS ON CHINESE MITTEN CRAB, ERIOCHER SINENSIS

To increase feed intake and reduce feed loss in the production of Eriocher sinensis, this study screened the attractants for Chinese mitten crab by pigment indication method using crabs of (26.4±0.17) g that were equally divided into 20 concrete tankages. To explore color preference and the optimum supplement dosages of five attractants of squid extract (SE), yeast hydrolysate (YH), cottonseed meal protein hydrolysate (CPH), betaine, and allicin, these five attractants were added pigment of different colors. The results showed that color did not significantly impact on feeding of crab (P>0.05). The stimulant index of fed 0.3% SE, 0.6% YH, 0.6% CPH and 0.09% allicin diets were significantly (P<0.05) higher than that of the control diet. The highest stimulant index of betaine was 1%, but there was no significant difference among other groups (P>0.05). The highest stimulant index was observed in 0.6% CPH group, and the stimulant index of 0.6% CPH and 0.6% YH diet was significantly (P<0.05) higher than other groups. The stimulant index of 0.3% SE diet was higher than 0.09% allicin diet group and 1% betaine diet group (P<0.05). In conclusion, the optimum supplement dosages of SE, YH, CPH, betaine and allicin for crab were 0.3%, 0.6%, 0.6%, 1% and 0.09% orderly and diets preference were following: CPH>YH>SE>allicin>betaine. The 0.6% CPH or 0.6% YH had stronger attractive effect among the attractants, which can be used as attractants of crab.