Mud crab

I. Problem/QuestionThere is currently an increasing commercial viability of mud crabs especially in subtropical countries. However, due to seasonal factors affecting the spawning of these species, there a need to develop methods for â€Å"year-around larval production† (Zeng, 2007, p. 1478-1479) arises. There are no current techniques that would enable this process. Therefore, this study investigated on the feasibility of out-of-season mud crab spawning induction. It also determined whether in vitro incubation of eggs is possible.   An evaluation of the temperature effects on the rates of embryonic development of mud crabs was also conducted. This is in order to provide predicted dates of hatching for berried mud crab females (Zeng, 2007, p. 1478-1479). II. Experimental procedures/MethodThe researchers kept female individuals of S. paramamosain in 1000L tanks. These holding tanks contained seawater, filtered with sand, with constant salinity of 29-32 g/L but with uncontrolle d temperature between 10-30  °C.   In order to determine the â€Å"proximate maturation index (PMI)† (Zeng, 2007, p. 1479), crab ovarian development was regularly checked every fortnight using a calliper to measure the width of the strip of light in the carapace when shone with bright light from underneath (Zeng, 2007, p. 1479).The induction experiment was started with the random selection of mature subjects with