Passos, A., L. Narciso
Penaeus kerathurus reproduction in captivity is considered by many authors quite problematic since females maturation and males fertility present several problems. Two groups of wild animals from the Sado estuary (Portuguese occidental coast) were used. The first one was processed immediately after its arrival into the laboratory while the second was maintained in a closed system at a constant water temperature (22 C) and salinity (35ppt) fed on Hedistes diversicolor ad libitum. Spermatophores were removed manually and the sperm counts point out a 60% decrease after one week of captivity.
Lipid nutrition (mainly the fatty acid profile) has been referred as one of the major factors that can interfere with maturation, reproduction and spawning of penaeid shrimps in captivity. Albeit H. diversicolor diet has been cited as trigger for the induction of P. kerathurus maturation our results point out that males fed on this live diet under laboratory conditions developed a high degree of infertility in terms of sperm counts decrease. In all studied organs (hepatopancreas, spermatophore ampoules, and testis) the captive animals present a significant improvement in the fatty acid profile, such as the increase of total FAME, DHA/EPA and n-3/n-6 ratios.
(Laboratorio Maritimo da Guia, Departamento de Zoologia e Antropologia Faculdade de Ciencias da Universidade de Lisboa Campo grande P-1700 Lisboa, Portugal)
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