Serotonergic stimulation of ovarian maturation and hemolymph vitellogenin in the Indian white shrimp, Fenneropenaeus indicus

The effect of serotonin (5-hydroxytryptamine, 5-HT) injection on the ovarian maturation and vitellogenin levels of Fenneropenaeus indicus was investigated. Female shrimp were assigned under as many as five ovarian stages. The neurotransmitter was evaluated at doses of 2.5 x 10(-6), 2.5 x 10(-7) and 2.5 x 10(-8) mol/g live mass. The effect was compared against a control group, which received the injection of the sterile vehicle solution. Serotonin induced ovarian maturation and increased vitellogenin concentrations at a dose of 2.5 x 10(-6) mol/g live mass. Ovarian development and vitellogenin levels were determined during the reproductive and non-reproductive moult cycles in order to examine the relationship between vitellogenesis and moulting. During the reproductive moult cycle, the ovary developed synchronously with the advancement of moulting stages. The results of the present study reveal the possible stimulatory role of serotonin on the ovarian maturation of F indicus by increasing the vitellogenin levels. (C) 2009 Elsevier B.V. All rights reserved.