Ultrastructural Deformities in the Scales of Cyprinus carpio Inhabiting Two Government-Sponsored Fish Farms in North-East India Contaminated by Municipal Wastes and Other Pollutants.

Scanning electron microscopy of the scales of Cyprinus carpio, inhabiting two government-sponsored fish farms, with different sources of pollutants, in the North-East state of Meghalaya, India revealed extensive damage to them. Lepidonts, which are teeth-like structures present on the edge of circulii, were discovered to be either partly or completely damaged. The dislodgment of complete rows of lepidonts along with broken lepidonts was also observed. Loss of symmetry and torn areas of circulii are some of the abnormalities also observed as compared to control samples. The alterations observed could be because of the high sensitivity of the scales to environmental stress and their capacity to react to low concentrations of pollutants, which makes them a sensitive bioindicator of water pollution. The study hence not only represents an advance in pollution research, by employing a highly sophisticated analytical approach to reveal the above-mentioned microstructural scale abnormalities, but it can also have scientific impact on the society at large and the fish culturist in particular in understanding the destructive impact of pollution caused by mismanagement of city garbage and agricultural effluents.

Microscopy and Microanalysis of Blood in a Snake Head Fish, Channa gachua Exposed to Environmental Pollution.

Conventional and highly sophisticated analytical methods (Cyria et al., 1989; Massar et al., 2012a) were used to analyze micro-structural and micro-analytical aspects of the blood of snake head fish, Channa gachua, exposed to municipal wastes and city garbage. Red (RBC) and white blood cell (WBC) counts and hemhemoglobin content were found to be higher in pollution affected fish as compared with control. Scanning electron microscopy revealed the occurrence of abnormal erythrocytes such as crenated cells, echinocytes, lobopodial projections, membrane internalization, spherocytes, ruptured cells, contracted cells, depression, and uneven elongation of erythrocyte membranes in fish inhabiting the polluted sites. Energy-dispersive X-ray spectroscopy (EDS) revealed the presence of silicon and lead in the RBCs of pollution affected fish. Significance of the study includes the highly sophisticated analytical approach, which revealed the aforementioned micro-structural abnormalities.