Original scientific paper
https://doi.org/10.14798/73.1.788
COMPARATIVE GROWTH PERFORMANCE OF MALE MONOSEX AND MIXED SEX NILE TILAPIA (Oreochromis niloticus L.) REARED IN EARTHEN PONDS
Cecilia Muthoni Githukia
; Kenya Marine & Fisheries Research Institute (KMFRI), Kegati Aquaculture Research Station, P.O Box 3259, Kisii, Kenya
Erick Ochieng Ogello
; Kenya Marine & Fisheries Research Institute (KMFRI), Kegati Aquaculture Research Station, P.O Box 3259, Kisii, Kenya
Elijah Migiro Kembenya
; Kenya Marine & Fisheries Research Institute (KMFRI), Kegati Aquaculture Research Station, P.O Box 3259, Kisii, Kenya
Alfred Otieno Achieng’
; University of Eldoret, Department of Fisheries and Aquatic Sciences, P.O Box 1125, Eldoret, Kenya
Kevin Odhiambo Obiero
; Kenya Marine & Fisheries Research Institute (KMFRI), Sangoro Aquaculture Research station, P.O Box 136 Pap - Onditi, Kenya
Jonathan Mbonge Munguti
; Kenya Marine & Fisheries Research Institute (KMFRI), National Aquaculture Research Development & Training Center, P.O. Box 451, Sagana, Kenya
Abstract
Comparative growth performance of male monosex and mixed sex Nile tilapia (Oreochromis niloticus) was conducted in six earthen ponds each measuring 150 m2 at the Kenya Marine & Fisheries Research Institute (KMFRI), 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-α-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.
Keywords
male monosex; mixed sex; Nile tilapia; growth performance
Hrčak ID:
137589
URI
Publication date:
25.3.2015.
Visits: 2.601 *