Surveying effects of fixation in formalin on the morphological characteristics of goldfish (Carassiusauratus)

Formalin is one of the important fixator in fish studies, and has many effects on morphological indices of fishes, so in this study the effect of this fixation was examined. The present study was done to investigate the effects of fixing and preserving in 10% formalin on the morphological characteristics of goldfish (Carassiusauratus). For this aim, 30 specimens of goldfish were collected from the Researches Center of Aquaculture, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran. After initial evaluation on morphological characters such as Total Length (TL), Standard Length (ST) and Head Length (HL), samples were fixed and preserved in 10% w/v formalin for 11 weeks. After this period, samples were removed from formalin and measurement and evaluation of color features were done once again. The results showed shrinkage was common in all of the specimens and changes in body color were clearly distinguishable with fresh fish such a way that the body and fins color were opaque but color pattern is acceptable but the intensity is reduced.

کلیدواژه ها:

Formalin ، Carassiusauratus ، Morphological characteristics ، Fixation