Reproductive biology and histological profiling of maturity stages in Hilsa shad, Tenualosa ilisha (Teleostei: Clupeidae) in the mouth of Perak waters, Malaysia

Abstract

This study was the first study that was conducted to evaluate the reproductive biology and histological profiling of this Tenualosa ilisha off Bagan Datoh, Perak waters. 1,174 samples have been collected at Bagan Datoh jetty since March 2017 to December 2019. Information on length-weight and ovary weight were recorded. Ovaries were grouped into four stages morphologically and histologically. The stage IV ovaries from 21 samples were subjected to fecundity assay whereas another 200 ovaries were subjected to histological assay. The ration of male to female sample was 2.3: 1. Only 21.5% of female and 11% of male sample reached the length at first maturity (Lm) size. Length weight relationship of female and male were given by equation BW = 0.00002FL3.0162 (isometric) and BW = 0.00005FL2.8066 (negative allometric). Results revealed that spawning season for Hilsa shad is in March - May with the fecundity of 172,951 to 1,219,040 oocytes.