2. Materials and methods
2.1. Experimental animals
Mature female freshwater prawns, M. rosenbergii (42.71±5.82 g
body weight) were obtained from commercial farms in Chonburi
Province, Thailand. The animals were kept in a 1400 L circular
concrete tank (80cm depth, 150 cm diameter). About 30% of the
water was changed every 2 days. Prawns were fed commercial
food pellets twice per day. Aeration was given all day. Thirty small
plastic cages were added in the tank for molting animals to hide in and avoid being killed from the cannibalistic behavior of this
species. Fifty prawns were used in this study, and twenty-five
female prawns were reared in the presence of five fully mature
males in a tank. Prawns were acclimatized under a photoperiod of
12:12 h light–dark, at 25–30 ◦C, for 2weeks before the animalswere
sacrificed, and CNS and ovarywere dissected out and processed for
immunohistochemistry.