Some histopathological effects of Aroclor 1254 on the liver and gonads of rainbow trout, Salmo gairdneri and carp, Cyprinus carpio

Sexually mature ♂ and ♀ rainbow trout ( Salmo gairdneri Richardson) and carp ( Cyprinus carpio L.) were injected intraperitoneally with Aroclor 1254 (25 mg kg⁻¹ body weight in 1 ml of arachis oil) once weekly for four weeks. Arachis oil was used as the control. At the end of the fourth week, samples of the liver, testis and ovary were taken from treated and control fish and examined by light and electron microscopy. The light microscope study indicated that there was general vacuolation of the hepatocytes of trout but not carp; fragmentation of the developing oocytes but no observable changes in the testis. Electron microscopy study showed that there was enlargement of the rough endoplasmic reticulum of the hepatocytes, some damage to spermatozoa and proliferation of the smooth endo- plasmic reticulum of the oocytes.