Growth performance of labeo rohita under chronic dual exposure of water-borne and dietary cobalt

In the present study the growth performance of three age groups viz.,60-,90-and 120-day of labeo rohita has been studied after exposure of fish to water-borne and dietary cobalt concentrations,for 12 weeks. it was found that wet weight of fish was significantly increased,whereas fork and total length did not show any significantly change. the 120-day old fish group exhibited higher average wet weight,fork and total length compared with the 90-and 60-day old fish age groups. the three age groups showed higher feed intake than the stressed fish age groups. the feed conversion ratios of the three age groups during controlled conditions were minimum compared to the cobalt stressed media. it was observed that non-significant variations existed for condition factor during the investigation period of 12 weeks among the three age groups of fish. however,the condition factor of stressed fish was significantly lower (1.380.45) than observed for un-stressed fish as 1.420.39. copyright © 2016 zoological society of pakistan.