Hi Sinan,

I found useful the following paper:

Froese, R. 2006. Cube law, condition factor and weight–length relationships: history, meta-analysis and recommendations. Journal of Applied Ichthyology. Vol. 22 (4): 241-253.

That paper is really useful, I recomend it

It depends if you are looking at morphological indices only or are also considering biochemcial indices. If the latter you should Google Scholar to search for papers by Catriona Clemmensen and also Benjamin Ciotti who have done nice research on use of RNA:DNA based indices in fish larvae and juveniles. In the 1980s-1990s there was also a lot of interest in use of lipid-based condition indices for larvae - have a search for papers by John Sargent's group e.g. Fraser, A. J., J. R. Sargent, J. C. Gamble, and P. MacLachlan. 1987. Lipid class and fatty acid composition as indicators of the nutritional condition of larval Atlantic herring. American Fisheries Society Symposium 2:129-143.

Thank you for answers. It seems biochemical methods are much more sensitive. But, unfortunately, I am working with an old data and it is mostly depend on morphological measuremets. By the way I found some other good literature on this subject for followers of this question:

Bolger, T., & Connolly, P. (1989). The selection of suitable indices for the measurement and analysis of fish condition. Journal of Fish Biology, (1 989). Retrieved from http://onlinelibrary.wiley.com/doi/10.1111/j.1095-8649.1989.tb03300.x/full

Diaz, M., Arano, M., & Pajaro, M. (2013). The use of morphological and histological features as nutritional condition indices of Pagrus pagrus larvae. Neotropical …, 11(3), 649–660. Retrieved from http://www.scielo.br/scielo.php?pid=S1679-62252013000300649&script=sci_arttext&tlng=pt

Jakob, E., Marshall, S., & Uetz, G. (1996). Estimating fitness: a comparison of body condition indices. Oikos, 77(1), 61–67. Retrieved from http://www.jstor.org/stable/10.2307/3545585

Any other additions may appreciated greatly