Growth Performance and Substrate Preference of Juvenile Mexican Dwarf Orange Crayfish (Cambarellus patzcuarensis) in Different Substrate Types

Abstract

Substrate is very important factor on growth and survival for crayfish in their entire life. Survival rate and growth of juveniles of the Mexican dwarf orange crayfish ( Cambarellus patzcuarensis ) were evaluated in aquaria with six different substrates covering their bottom. The six different substrates were plastic mesh, pebble, sand, basalt and calcite and bare glass without a cover as a control group. The study was carried out in two different experimental areas. In the first experiment, ten (mean body weight 0.25±0.01 g) juveniles were stocked in aquaria with above mentioned six substrates and each substrate in three replicates. After 100 days, the best weight gain was observed in the group raised on basalt substrate (P<0.05). In the second experiment, juveniles were individually placed in a hexagonal glass aquarium divided into six sections each containing one of the same substrates used in the first experiment was used for substrate preference. Each individual was filmed for 24 h, and the time spent in each compartment was registered. Basalt was the most preferred substrate for Mexican dwarf orange crayfish (P<0.05). The preference of basalt substrate can be explained by its proximity to the natural substrate of this species.