COMPARATIVE GROWTH PERFORMANCE OF MALE MONOSEX AND MIXED SEX NILE TILAPIA (Oreochromis niloticus L.) REARED IN EARTHEN PONDS
Year: 2015
Type: article
Abstract: Comparative growth performance of male monosex and mixed sex Nile tilapia (Oreochromis niloticus) was conducted in six earthen ponds each measuring 150 m 2 at the Kenya Marine & Fisheries Research Institute (KM-FRI), Kegati Aquaculture Research Station.Male monosex and mixed sex of O. niloticus juveniles at an average weight of 12.2 ± 0.02 g and average length of 7.6 ± 0.02 cm were collected from nursery production ponds.The male monosex juveniles were obtained by feeding newly hatched juveniles with feed dosed with 17--methyltestosterone hormone for a period of one month.Stocking was at 3 juvenile m -2 and feeding was carried out using 28% crude protein diet twice daily for six months at 4% body weight.Selected water quality parameters (dissolved oxygen, temperature, pH, electrical conductivity and total ammonia nitrogen) were measured weekly in situ, while sampling for weight and length measurements was conducted on a monthly basis for a period of six months.Specific Growth Rate (SGR), Feed Conversion Ratio (FCR), Condition Factor (CF) and survival rate (%) were measured at the end of six months.Data were subjected to one-way analysis of variance (ANOVA).At the end of six months, the average weight of male monosex and mixed sex fishes was 200.8 ± 0.81 g (mean ± SE) and 123.4 ± 0.76 g, respectively, while the average length of male monosex and mixed sex was 22.4 ± 0.21 cm and 18.6 ± 0.23 cm, respectively.The male monosex O. niloticus achieved significantly increased final weight and length, SGR, FCR and CF than the mixed sex O. niloticus (p < 0.05).However, both male monosex and mixed sex fish recorded similar survival rates (p > 0.05).There were no significant differences in mean water quality parameters in male monosex and mixed sex ponds (p > 0.05).The male monosex fish performed better because most energy was spent on muscle and tissue development while the mixed sex fish spent most energy on reproduction activities at the expense of muscle and tissue development.Further studies should be done in other culture systems such as liner ponds, tanks, cages and raceways.
Source: Croatian Journal of Fisheries
DOI: 10.14798/73.1.788
Language: English
Subfield: Aquatic Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: bronze
OpenAlex ID: W2140835211