The effects of different diet, salinity and light condition on growth performance and moulting cycle of juvenile mud crab, Scylla paramamosain

Scylla paramamosain is an importantly economical mariculture crab. To figure out the optimized conditions in the culture of juvenile crabs, three experiments were conducted to examine the effects of diet, salinity and light condition on the growth performance (body weight gain, BWG; carapace width gain, CWG; carapace length gain, CLG) and moulting cycle (MC) of crablets from V to VII stages. The growth performances of the crablets from stages V-VII have no significant differences after feeding different diets. However, the MC of crablet V fed Artemia or mixed fish were significantly shorter than that fed artificial diet. The CLG of crablet VI in salinity 25 parts per thousand was significantly higher than that in salinity 15 parts per thousand, while the CWG and CLG of crablet VII in salinity 15 parts per thousand were significantly higher than that in salinity 5 parts per thousand. The MC of the crablets V-VI reared in salinity 25 parts per thousand and 15 parts per thousand were significantly shorter than that in salinity 5 parts per thousand, while it was significantly shorter in salinity 25 parts per thousand than that in salinity 15 parts per thousand from crablets VI-VII. For light conditions, the BWG of crablet VI with full cover was significantly higher than that with half cover. Whereas, the MC of the crablets V and VI with full cover was significantly shorter than that without cover or half cover. These findings indicated that crablet V and VI may prefer to exposing to 25 parts per thousand salinity and dark environment and feeding on Artemia for faster growth. Thus, the current findings may serve as a guide for establishing appropriate conditions in the aquaculture of juvenile mud crabs.

Automated summary

This study examined the effects of diet, salinity, and light conditions on the growth and moulting cycle of juvenile Scylla paramamosain. The findings indicate that diet and salinity have significant effects on the growth performance and moulting cycle of the crablets, while light condition only affects the growth performance. The results can provide guidance for establishing appropriate conditions in the mariculture of juvenile mud crabs.