Effects of Water Temperature on Growth Criteria of Fingerlings of Grass Carp, Ctenopharyngodon idella (Valenciennes, 1884)

Abstract

The current experiment was conducted in the Fish Laboratory of Aquaculture Unit, College of Agriculture, University of Basrah from 28th January to 19th April 2021. Growth criteria of grass carp Ctenopharyngodon idella were investigated using four water temperatures (15, 20, 25 and 30 oC). Grass carp fingerlings (4.92 g) were brought from earthen ponds of the Aquaculture Unit in Al-Hartha Station for Agricultural Researches, North Basrah. The results indicated that the highest final weight (7.96 g) was reached by fishes at 15 0C, while the lowest final weight (7.22 g) was at 30 0C. Weight increments for fishes were 3.02, 2.97, 2.76 and 2.22 g for water temperatures of 15, 20, 25 and 30 0C, respectively. Fishes had the highest daily growth rate (0.0425 g/day) at 15 0C and the lowest (0.0312 g/day) at 30 0C. Fishes at 20 0C had the best feed conversion rate of 4.03, while fishes at 30 0C had the worst feed conversion rate of 5.29. It can be concluded that the best growth criteria were obtained from fishes at 15 0C and 20 0C, while the worst was observed at 30 0C.