Reproductive Performance of Male Argentine Red Shrimp Pleoticus muelleri Bate (Decapoda, Penaeoidea) in Culture Conditions

Abstract

AbstractSpermatophore and sperm quality of male Argentine red shrimp Pleoticus muelleri held under laboratory conditions was evaluated using compound spermatophore weight, sperm count and percentage of live sperm as indicators. Thirty‐seven males of S to 20 g wet weight were held indoors in a 3‐m diameter circular fiberglass tank for 45 d. They were fed fresh squid, clam and pelletized diet. Spermato‐phores were obtained by manual ejaculations. Four shrimps were re‐ejaculated to verify the subsequent spermatophore regeneration. Spermatophore mean weights were significantly lower for 5–10 g males than for 15–20 g males (r= 0.998) (P < 0.05). There were no significant differences in sperm count and percent live sperm among the different weight classes (5–15 g, 15–20 g, 20–25 g). The sperm count varied from 2.22 to 5.62 million. No change in sperm quality was seen in re‐ejaculated individuals. During the first 2 wk of the experiment, the spermatophores exhibited healthy morphology and colour; by the fifth week evidence of spermatophore deterioration was apparent. Despite the degree of melanization, sperm quality was not affected and the high variability in sperm count indicated that the artificial ejaculation is adequate in this species.