Effects of Different Ethanol Concentrations on the Morphometric Characteristics of Clarias gariepinus and Oreochromis niloticus

The effects of ethanol (90% and 95% concentration) preservation on the morphometric characteristics of Clarias gariepinus and Oreochromis niloticus were investigated. The morphometric characters observed were total length, standard length, head length, body depth, eye diameter, and total weight for the period of sixty-three (63) days. Samples were first euthanized before taking the morphometric characteristics after which the samples were individually preserved in separate bottles filled with respective concentrations (90% and 95%) for nine weeks (63 days). Morphometric characteristics of the samples were later measured at the end of the 63 days to determine any possible changes. The results indicated that varying degree of shrinkage was common in all the observed morphometric characters in both species even though they both reacted differently to different concentration of alcohol. The results also revealed that the percentage shrinkage in all measured morphometric characters was higher in C. gariepinus than in O. niloticus and higher in 95% concentration than in 90% concentration.