Effects of waterborne iron on fry of Catla catla (Ham.), Labeo rohita (Ham.) and Cirrhinus mrigala (Ham.) Debnath Mitra, Saha Ratan Kumar*, Kamilya Dibyendu, Saha Himadri Department of Fish Health and Environment, College of Fisheries, Central Agricultural University, Lembucherra, Tripura-799 210, India *Corresponding author’ e-mail: ratankumarsaha123@rediffmail.com
Online published on 12 August, 2015. Abstract Effects of waterborne iron on Indian major carps (Catla catla, Labeo rohita and Cirrhinus mrigala) fry was evaluated in the present study. In short-term definitive test a concentration series of 8, 10, 12, 14, 16, 18, 20, 22 and 24 mg l−1 of iron were selected. In long-term partial life cycle test 1.0, 2.0, 3.0, 5.0 and 6.0 mg l−1 of iron were selected to observe the behavioural changes, feeding rate, growth rate and bioaccumulation of iron in different organs of fishes. Supplement of iron was done by adding FeSO4 to get the test concentrations. Rohu showed highest tolerance to iron toxicity. The lowest 96 h LC50 value was found for mrigal as 11.21 ± 0.53 mg l−1 whereas the highest was observed in rohu as 16.75 ± 0.96 mg l−1. Among the organs tested, comparatively gill showed higher iron accumulation and muscle showed the lowest. However, rate of change of iron accumulation in gills w.r.t toxicant concentration was lowest as compared to other tissues. Histopathological study of gill showed the evidence of iron accumulation and erosion of secondary gill lamellae. In long-term partial life cycle test reduction in feeding rate, behavioural changes and reduced weight gain was observed. Mrigal showed highest accumulation and catla showed the lowest. Top Keywords Bioaccumulation, Environmental parameter, Gill erosion, Indian major carps, Iron toxicity, 96 h LC50. Top |