Physiological Responses of Freshwater Ornamental Fish Koi Carp, Cyprinus carpio (L.) in Inland Saline Water: Growth and Haematological Changes

摘要

Four month experimental study was carried out to assess the performance of freshwater ornamental fish, koi carp, Cyprinus carpio (Linnaeus) in different salinity levels w.r.t. survival, growth and haematological parameters. Inland saline water (55 ppt) collected from district Fazilka (Punjab) was used for preparation of different treatment salinities viz., 2,4,6,8,10 and 12 ppt. The pH and NHS-N did not vary significantly and these remained in tolerable range for fish culture. The rest of the parameters (EC, TA, and TH) and ionic composition (Na~+, K~+, Ca~(+2), Mg~(+2), CI~(-1) and SO_4~(-2)) of water differ significantly and maximum values for these parameters were observed in maximum salinity treatment (12ppt). No negative effect of salinity wasobserved on fish survival and growth. Hb, PCV and RBC showed significant increase with increasing salinity up to 12 ppt, whereas WBC increased significantly up to 10 ppt. The variations in haematological indices (mean corpuscular volume, mean corpuscularhaemoglobin and mean corpuscular haemoglobin concentration) were in accordance with haemoglobin, packed cell volume and red blood cells. Overall results are indicative of stimulation of defense mechanism in fish for maintaining balance state of ions andwater to achieve internal stability or homeostasis.