Assessment of Morphology and Nuclear Abnormalities in Freshwater Fish Specimens

Olivia Chakraborty, Soumendra Nath Talapatra

Abstract: The objective of the present study was to detect the morphological anomalies and nuclear abnormalities especially induction of micronuclei (MN) and abnormal nuclei (NA) in the peripheral erythrocytes of deformed fish (Oreochromis niloticus Linn.) collected from the Barasat market, West Bengal. The specimens were collected as per visual observation among normal and abnormal morphological features followed by MN and NA test after visualizing under brightfield binocular microscope. External morphologies of deformed fish specimens were observed bulging at lateral side and bending at trunk and tail region. Regarding mutational risk, micronuclei, notch nuclei, blebbed nuclei and nuclear cariolysis were identified in the peripheral erythrocytes of studied fish specimens. In conclusion, the abnormal external morphology induced the mutagenic effect in the studied fish specimens. Although the causative factors are unknown. Further study is suggested to analyse the mutagenic compounds such as metals and organic compounds in future.

Keywords: Abnormal morphology, Aquatic pollution, Fish market, Mutation risk, nuclear anomalies, Oreochromis niloticus