Control of Reproduction of the ShrimpPenaeus kerathurusHeld in Captivity

Abstract

The control of the reproductive cycle of the shrimp Penueus kerathurus, held in captivity from early juvenile stages without eyestalk ablation, was attempted in two sets of experimental conditions during two successive years. In the first set of experiments, light regime, sex ratio and presence of sand substratum were assessed in relation to ovarian maturation and successful mating. Examination of thelyca obtained from cast exoskeletons showed that 40–82% successful mating had taken place. A sex ratio of 2:l female/male gave a higher percentage of fertilized females than a ratio of 1:l. The induction to full ovarian development was observed for every treatment except the tank without sand substrate, where no mated females were observed. In the second set of experiments, the role of diet, in particular the role played by a polychaete Nereis diversicolor, was assessed as a nutritive stimulator to induce maturation and spawning. With the same purpose, a parallel experiment in smaller aquaria was also conducted to assess the relative importance of mussel, squid, ragworm and crab and four composite diets consisting of two or three of the said food organisms. Nereis worm seemed to have a determinant role on the induction of shrimp ovarian maturation and spawning. The possible role of its fatty acids on shrimp reproduction is discussed. The experimental results suggest the possibility for extended control of the reproductive cycle of P. kerathurus in a controlled environment provided that proper food is available.

Evaluation of lipid-enriched Artemia on the reproductive performance of the white-striped cleaner shrimp, Lysmata amboinensis

“…Marsden et al (1997) also found that EPA did not contribute to reproductive output in Penaeus monodon. It may be that the EFA requirements of L. amboinensis were partly met by the C18 PUFAs, similar to the reports for other crustaceans (Luis and Ponte 1993;Cavalli et al 1999;Palacios et al 2001).…”

The Effect of Maturation Diets on the Reproductive Output of the White‐striped Cleaner Shrimp, Lysmata amboinensis

“…Various essential FAs can impact on spawning quality; in M. rosenbergii increased dietary levels of LOA (ω-6 family) increased fecundity, measured as egg number per female weight (Cavalli et al 1999). Beneficial effects of high LOA on reproduction and offspring survival have also been reported for penaeids (Luis and Ponte 1993;Palacios et al 2001). A high concentration of C18 polyunsaturated fatty acids (PUFA) (including LOA) in the Artemia diet of L. amboinensis could be associated with high egg production, however, viable fecundity was low and may suggest a requirement for a different mix of FAs.…”

Influence of food regimes and seasonality on fatty acid composition in the ragworm

“…The feeding regime resulted in an increased number of eggs per spawning event for each female and increased egg viability and larval survival in shrimp (Briggs et al 1994) and more rapid maturation in cultured prawns (D'croz et al 1988, Luis & Ponte 1993 and sole (Diniz 1992). Nereidid worms contain large amount of essential PUFA, which allows broodstock conditioning for egg production by crustaceans (Lytle et al 1990, Olive et al 1992.…”