Effects of Water Temperature on Sex Differentiation and Growth Parameters of the Mozambique Tilapia (Oreochromis mossambicus, Peters, 1852)

Abstract

In this study, the effects of water temperature on growth, survival rate, gonad development and sex ratios of Mozambique Tilapia (Oreochromis mossambicus) were studied by applying different temperature applications (28, 30, 32, 34 and 36 o C) for a single period of 40 days. At the end of the study, in the control group (28 o C), the males proportion was 47.62%. In fishes reared at 30 o C, average male ratio was found as 73.68%. The highest male proportion was obtained in the 36 o C temperature group (86.67%). Growth performances, feed utilization and gonad development were found to increase with elevating temperatures up to 34 o C unlike the survival rate which has been found to fall with higher temperatures. In this study, sex differentiation rates differed significantly between all groups (p<0.05). However, the highest male rate obtained in group A and D. As hypothesized, results suggest that fish performed better at 30-32°C than 28°C or 34-36°C water temperature and the optimum temperature for a better expression of growth parameters in Mozambique Tilapia could be 30 o C.

Notes on the Distribution of the Genus Oreochromis in the East Mediterranean Region of Turkey

“…It was shown in 1993 that O. niloticus grew 60% faster than the other tilapias (Canonico et al, 2005). Besides, they have important characteristics to be selected as valuable aquaculture products, including the relationship between extreme environment conditions and sex-differences (Hekimoğlu et al, 2019;Dussenne et al, 2020), as a biomarker for disease control (Huang et al, 2018;Chen et al, 2019;Yin et al, 2018;Wu et al, 2019), and for evaluating the effects of environmental pollutants (Yıldırım et al, 2006;Benli & Ozkul, 2010;Beryl et al, 2019;Ibrahim, 2020). Hence, the Genetic Improvement of Farmed Tilapia (GIFT) program was established and GIFT has invested many types of research and projects to improve the farming performance of tilapias, especially in Asia (Dey et al, 2000).…”