Induced nest spawning and artificial hatching of the fertilized eggs of mudskipper, Boleophthalmus pectinirostris

In this study, nest spawning was successfully induced by exogenous hormone injections and seawater flow stimulation, and optimum condition for hatching fertilized eggs of burrow fish mudskipper, Boleophthalmus pectinirostris, was searched. Apart from spawning inside the nests, females also spawned outside the nests. The percentages of spawned nests were 8.0% to 24.2%. Most eggs were observed adhered to the inner wall of the top half of the nest. Fertilization rates of the nest-spawned eggs varied from 17.3% to 80.8%. Females could spawn after being artificially confined inside the nests with males at ratios of 1:1 or 1:2, but the spawned eggs were not fertilized. Mean hatching rates of artificially fertilized eggs incubated in round plastic buckets were 32.7%-70.6%, and in the net cages, were 4.2%-20.5%, respectively. Mean hatching rates of nest- fertilized eggs incubated in the round plastic buckets were 33.6%-76.3%, and in the net cages, were 5.9%-25.2%. Results showed that round bucket incubation was the best way for hatching fertilized eggs of mudskipper. Keeping the hatching seawater flowing is an important way for increasing the hatching rates of the mudskipper fertilized eggs.

人工管道诱导大弹涂鱼产卵研究

报道了人工制作的陶瓷管道诱导大弹涂鱼 Boleophthalmus pectinirostris产卵的研究结果。未经激素催熟的亲鱼放入产卵池内7—12d未见产卵，经一次激素注射催熟的亲鱼放入产卵池内第3天开始交配产卵和受精，入池后5d未能产卵雌鱼的卵母细胞开始退化吸收。雌鱼不仅在管道内产卵，而且也将卵产在管道外、池底和池壁，产卵时间集中在下半夜的02：00—04：00，不同产卵池中管道的产卵率差别很大。卵子粘附在管道不同部位的数量和受精率均不相同。强迫配对的亲鱼虽有产卵，但卵子不受精。