The relationship between haematocrit and some biological parameters of the Indian shad, Tenualosa ilisha (Family Clupeidae)

Haematological parameters have been recognised as valuable tools for the monitoring of fish health. Here we analyse the relationship between haematocrit and body length, sex and reproductive state in the Indian Shad Tenualosa ilisha. Haematocrit value showed a quadratic relationship to fish size (body length), incrementing as the fish body length increased up to 400 mm, after which it decreased. Male fish showed a higher haematocrit value than females. Haematocrit appeared to be higher in the pre–spawning period than in the spawning phase, but then increased slightly in the post–spawning period.