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Showing papers on "Polyculture published in 1969"


Journal ArticleDOI
TL;DR: Each of six 700-m 2 earthen ponds was stocked with all-male hybrid fingerlings from the cross of female Tilapia nilotica x male T. hornorum, and average weight of tilapia was 395 g among all ponds, independent of prawn density.
Abstract: Each of six 700-m 2 earthen ponds was stocked with all-male hybrid fingerlings (28 g) from the cross of female Tilapia nilotica x male T. hornorum , at a rate of 0.4 fish/m 2 . Six days later, duplicate ponds were stocked with either 0.5, 1.0 or 1.5 juvenile prawns ( Macrobrachium rosenbergii ) (2 g) per m 2 . Initially 32% protein pellets were fed daily at 2.5% of fish biomass; this ratio was decreased to 1.4% by harvest. At the low, medium and high prawn densities, average yields after 20 weeks were 171, 243, and 350 kg/ha lor prawns and 1,404; 1,450; and 1,356 kglha for tilapia, respectively. At these densities, 84.4, 87.7, and 85.4% of the prawns weighed 30 g or more, whereas 75.0, 67.5, and 71.3% weighed 40 g or more, respectively. Average weight of tilapia was 395 g among all ponds, independent of prawn density.

6 citations