Effects of Prawn Shell Meal Diets on Hemocyte Count, Hemolymph Clotting, and Sperm Quality of the Freshwater Prawn Macrobrachium caementarius

Crustacean shells are composed of chitin, which is bound to protein and minerals, along with other essential nutrients. These components are necessary for growth, immune response, the formation of reproductive structures, and the enhancement of sperm quality. This study aimed to evaluate the effects of prawn shell meal diets on hemocyte count, hemolymph clotting, and sperm quality of the freshwater prawn Macrobrachium caementarius. The prawns were distributed into three dietary treatments, consisting of a basal diet (control) and two experimental diets supplemented with 20% raw prawn shell meal (RPSM) and 20% cooked prawn shell meal (CPSM). Hemocytes were counted, and the hemolymph clotting time was determined. Spermatozoa in spermatophores and the vas deferens were counted. Sperm quality was assessed by staining. The RPSM and CPSM diets did not lead to an increase in hemocytes, nor did they affect the clotting time of the hemolymph. However, with the RPSM diet, there was an increase in the number of normal spermatozoa in the entire vas deferens (from 3.65–8.11 × 10⁵ spz/mL) and a lower proportion of dead and abnormal spermatozoa (<2 × 10⁵ spz/mL). These findings suggest the potential of RPSM and CPSM diets to improve sperm quality in the freshwater prawn. Further research based on isoproteic and isolipidic diets should be performed to ascertain whether RPSM could increase reproductive performance in male individuals of the freshwater prawn.