Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Substitution of organic manure for pelleted feed in tilapia production.

Abstract

The partial substitution of organic manure for pelleted feed in monosex Oreochromis niloticus (20 000/ha) production ponds was studied in Honduras. Treatments were: pelleted feed only (23% protein; 3% fish biomass/day), organic manure (chicken litter 1000 kg total solids (TS)/ha weekly) only during the first 60 days, followed by pelleted feed only, and organic manure (chicken litter 500 kg TS/ha weekly) and pelleted feed (1.5% fish biomass/day) given simultaneously. Mean gross yields after 151 days were 5305, 4794 and 4351 kg/ha for treatments 1 to 3, respectively. At harvest, fish averaged 262, 284 and 251 g/fish, respectively. No differences were detected among treatments for gross yield or average individual weight. Feed conversion ratio for treatment 1 (1.83) was significantly greater than for treatment 3 (0.95). It was concluded that layer chicken litter can replace 27 to 58% of pelleted supplemental feed without significantly affecting tilapia yield. Total production costs from enterprise budgets were US $5336/ha (feed only), $4645/ha (manure followed by feed), and $3471/ha (manure and feed simultaneously).