| 英文摘要 |
Crab larvae, megalopa used in this study were captured from wild. Crab larvae were acclimatized in 12 ton cement tanks, and fed with Artemia nauplii and commercial feed twice daily prior to experiment. Some of megalopa metamorphosed to juvenile after 3 days of acclimation, and all of megalopa became juvenile after 10 days of acclimation. The survival of crab juvenile was 64.6% during the acclimation. Thereafter, similar sizes of juvenile were selected for the trials of cannibalism improvement by setting different shelters in crab cultured tanks. Two trials of cannibalism improvement by using shelters were carried out with two sizes of crab, including 0.09 g and 20.1!O0.8 g, respectively. In the first trail with 0.09g crab, the survival of crab was significantly lower in the control (without shelter) (43.33%) than the treatment using the 2 inch of plastic tube as shelter (31.66%). However, significant higher survival was found in the treatment with the sinking black net used as shelter (63.33%). For the second trial, crab in the treatment with 2 inch of plastic tube as shelter has a significant higher survival (40!O1.53 %) compared to the control and the rest of treatment. In addition, the result of the treatment with the suspended black net for moulted crab hiding showed that the suspended black net in tank could reduce the problem of cannibalism. For the 125 days of mud crab monoculture, the shelters of suspended and sinking black nets, and plastic tubes were placed in the rearing tank (300 m2) for crab hiding. At the end of growth out trial, total 181 crab (including 164 crab reached to marking size with a mean weight of 201.2!O1.61g) were harvested. The survival and total production of crab was 18.1% and 33 kg, respective |
