饵料对鹄沼枝额虫生长和生殖力的影响

鹄沼枝额虫是一种淡水小型甲壳动物,主要以细菌、有机碎屑和单胞藻等为食.用豆腐、虾片、米糠、大豆、面粉、小球藻6种饵料培养鹄沼枝额虫幼体,经11d培育,结果显示,不同饵料对鹄沼枝额虫生长、成活率有显著影响.方差分析表明,虾片组的鹄沼枝额虫体长增长显著优于其他5种饵料组(P<0.05);小球藻组的鹄沼枝额虫成活率显著高于米糠、豆腐和面粉组(P<0.05),但与虾片和大豆组没有显著性差异(P>0.05).虾片培养的鹄沼枝额虫较其他5种饵料提早1-2d产卵,且初次产卵量和卵径均为最大.用虾片、大豆、米糠、虾片+米糠、大豆+米糠5种饵料投喂性腺刚开始发育的鹄沼枝额虫,经27d培育,结果表明,不同饵料组间的鹄沼枝额虫生殖力差异显著.虾片+米糠培育的鹄沼枝额虫生殖总量显著高于米糠和大豆(P<0.05),而与虾片和大豆+米糠组没有显著性差异(P>0.05).因此,虾片和虾片+米糠是培养鹄沼枝额虫的优质饵料,对其生长和种群增殖有明显的促进作用.

Effect of diets on growth and fecundity of Branchinella kugenumaensis

Branchinella kugenumaensis, a small freshwater crustacean creature, mainly feeds on bacteria, organic debris and unicellular algae etc. Juvenile Branchinella kugenumaensis were cultured for 11 days by feeding six diets including tofu, artemia flake, rice bran, soybean, floure and Chlorella sp respectively. The results showed that growth performance and survival rate of Branchinella kugenumaensis were significantly affected by various diets. Statistical analysis by one-way ANOVA indicated that body length increment of experimental animal fed artemia flake was significantly higher than those of the other 5 treatments (P<0.05); the survival rate of Branchinella kugenumaensis fed Chlorella sp was significantly higher than those of groups fed rice bran or tofu or flour (P<0.05), and had no significantly difference with those of groups fed artemia flake or soybean (P>0.05). It was also observed that Branchinella kugenumaensis fed artemia flake began to lay eggs one or two days earlier and had the most egg numbers of the first batch and biggest egg size in diameter, comparing with other treatments. In a further experiment, Branchinella kugenumaensis with infancy development of sexual organ were cultured with five diets including artemia flake, soybean, rice bran, artemia flake with rice bran and soybean with rice bran respectively for 27 days. The fecundities showed significantly difference among dietary treatments. The reproduction capacity of Branchinella kugenumaensis fed mixture of artemia with rice bran was significantly higher than those of groups fed rice bran or soybean (P<0.05), and had no significantly difference with those of groups fed artemia flake or mixture of soybean with rice bran (P>0.05). In conclusion, artemia flake and mixture of artemia flake with rice bran were proper diets for the culture of Branchinella kugenumaensis, which could enhance the growth and mass multiplication of this animal obviously.