Nile tilapia (Oreochromis niloticus) seed production and growth performance of fry and grower broodstocks in Northwest Ethiopia

Abstract

Small-scale Nile Tilapia (Oreochromis niloticus) fry production is essential for improving seed availability and supporting sustainable aquaculture. This study evaluated the biological performance and economic feasibility of Nile tilapia fry production in earthen ponds using a locally formulated diet under small-scale farming conditions in Ethiopia. Thirty-three broodstock fish (11 males and 22 females) collected from the Geray Reservoir region were stocked in a 100 m² earthen pond at a male-to-female ratio of 1:2 and fed a locally formulated diet containing 35% crude protein at 3% of body weight per day. The diet consisted of fish meal (38.1%), soybean meal (38.1%), and wheat bran (24.0%), offered twice daily. Male brood stocks showed significantly greater growth performance than females (P < 0.001). Each spawning cycle produced approximately 3,300 fry, and broodstocks spawned an average of eight times annually, yielding about 1,200 fry per female and an estimated annual production of 26,400 fingerlings. Fry reared in the best-performing on-farm pond (researcher) achieved significantly greater final weight, final length, and daily growth rate than those reared at the other sites (farmers) (P < 0.001), while survival remained consistently high (98.75–100%) with no significant differences among sites. In water quality, no significant differences among sites for temperature, dissolved oxygen, pH, total dissolved solids and ammonia (P > 0.05), although electrical conductivity differed significantly (P < 0.001). Total feed consumption was 251.16 kg, corresponding to a total feed cost of US$105.94. The selling price was US$0.079 per fingerling. The production system generated positive economic returns. These findings demonstrate that earthen-pond-based Nile tilapia fry production using locally formulated feeds is a technically feasible and economically viable approach for increasing the availability of quality fingerlings. The technology has strong potential for dissemination through Farmers Training Centers to support sustainable aquaculture development, fisheries enhancement, and improved rural livelihoods in Ethiopia.