Quantitative histology of the seasonal changes in the gonads of summer whiting, Sillago ciliata

The histology of the gonads of free and captive summer whiting, Sillago ciliata, were compared to assess the potential of this fish for aquaculture. There were no qualitative differences between the free and captive males: both completed spermatogenesis through to spermiation. The captive females were non‐reproductive, reaching only the vitellogenic stage before the eggs were resorbed by atresia. A reproductive score was devised to assess reproductive potential in the comparison of the two populations. The females in the captive population had lower reproductive potentials, as shown by the score, and started development a month later than the normal free population. The captive males had higher reproductive scores than the free fish but they were also not spawning and, therefore, the higher score indicated that this potential was not realized. The score provides a standard against which experimental results can be compared and subsequently assessed. Copyrigh