Effects of Different Types of Substrates on Growth of Crayfish Cherax destructor (Clark, 1936)

Abstract

This research was to study the effect of different substrates (black earth soil, black Japanese pebble, and no substrate) on weight, length molting and growth rates (body weight) of crayfish C. destructor. Crayfishes used in the experiment had an average weight of 0.29±0.02 g and an average length of 1.87±0.10 cm.  Crayfishes were reared in glass aquarium tanks with different substrates at 27º C. The change in weight, length, molting and growth rates (body weight) were measured at the beginning and end of the experiment for eight weeks. It has been found that the growth rates (body weight) of crayfish reared in the tank with black earth soil, black Japanese pebble, and no substrate were 0.047±0.007, 0.054±0.005 and 0.040±0.007 g/day, respectively, which were statistically different (p <0.05). The mean weight changes were 3.02±0.31, 3.47±0.23 and 2.57±0.39 g, respectively, which were statistically different (p <0.05).  The mean length changes were 3.64±0.23, 4.62±0.26 และ 2.94±0.60 cm, respectively, which were statistically significantly different (p <0.05) The number of molts was an average of 5.33±0.71, 5.89±0.33 และ 3.78±1.09 times, respectively, with no significant difference between black earth soil and black Japanese pebble but the black Japanese pebble and black earth soil are statistically significant difference with the one that no substrate. Therefore, it is concluded that different substrates affect the change in weight, length molting and growth rate (body weight). The most suitable substrate for rearing crayfish C. destructor is the black Japanese pebble followed by black earth, soil and no substrate.