Objective:To monitor the response of gills of Cyprinus carpio var. communis to LC_(50) levels of ammonia over a period of 96 h by bath exposure, using scanning electron microscopy (SEM). Methods: Cyprinus carpio procu...Objective:To monitor the response of gills of Cyprinus carpio var. communis to LC_(50) levels of ammonia over a period of 96 h by bath exposure, using scanning electron microscopy (SEM). Methods: Cyprinus carpio procured from a local fish farm in Vadalore, Cuddalore District, Tamil Nadu, India were acclimatized under laboratory conditions for 20 d. Fish were placed into experimental tanks with 20 L of water and 22 mg/L ammonia. A total of 10 fish were collected from each experimental tank every 24 h for histopathological studies. Results:Histopathological studies showed these changes in the gills:secondary lamellar fusion, haemorrhage, oedema, epithelial hyperplasia, and chloride cell proliferation. Occasionally, multifocal necrosis of inter-lamellar regions of gill filaments but with no apparent haemorrhage was observed under electron microscopy. Conclusion:The present study shows that histopathological and ultrastructural alterations in gills are useful indicators for ammonia toxicity in Cyprinus carpio.展开更多
基金Supported by the Annamalai University Grants Commission[39-562/2010(SR)].
文摘Objective:To monitor the response of gills of Cyprinus carpio var. communis to LC_(50) levels of ammonia over a period of 96 h by bath exposure, using scanning electron microscopy (SEM). Methods: Cyprinus carpio procured from a local fish farm in Vadalore, Cuddalore District, Tamil Nadu, India were acclimatized under laboratory conditions for 20 d. Fish were placed into experimental tanks with 20 L of water and 22 mg/L ammonia. A total of 10 fish were collected from each experimental tank every 24 h for histopathological studies. Results:Histopathological studies showed these changes in the gills:secondary lamellar fusion, haemorrhage, oedema, epithelial hyperplasia, and chloride cell proliferation. Occasionally, multifocal necrosis of inter-lamellar regions of gill filaments but with no apparent haemorrhage was observed under electron microscopy. Conclusion:The present study shows that histopathological and ultrastructural alterations in gills are useful indicators for ammonia toxicity in Cyprinus carpio.
