Production of Nile Tilapia Oreochromis niloticus and Freshwater Prawn Macrobrachium rosenbergii Stocked at Different Densities in Polyculture Systems in Brazil

Abstract

Abstract.— The effect of stocking prawns Macrobrachium rosenbergii at increasing densities in ponds with Nile tilapia Oreochromis niloticus reared at low density was evaluated. Twelve 0.01‐ha earthen ponds were stocked with 1 tilapia/m2 and 0, 2, 4, or 6 postlarvae prawn/m2. Three replicates were randomly assigned to each prawn density. Postlarval prawns were stocked a week prior to tilapia juveniles and both were harvested 175 d after the beginning of the experiment. Tilapia final average weight, survival, production, and food conversion rates did not differ significantly among treatments (P > 0.05); the averages were 531 g, 67%. 3,673 kg/ha, and 1.91, respectively. Prawn survival rates did not differ for the three stocking densities (mean 90%). However, final weight and production were significantly different (P < 0.05) as follows: 34.0, 23.0, and 14.7 g and 639, 909, and 818 kg/ha, respectively for 2. 4, and 6 prawns/m2 densities. Stocking densities up to 6 prawn/m2 did not affect tilapia production and required neither additional feeding nor significant changes in management. The polyculture system allowed an increase in total production with the same amount of supplied feed, thus improving the system sustainability.

Stocking densities and feeding strategies in shrimp and tilapia polyculture in tanks

“…Tilapia survival (84 to 85%) in the present experiment was: similar to the one reported by Bessa Junior et al García-Pérez et al (2000) also reported no significant differences in prawn performance between monoculture (7 prawns per m 2 ) and polyculture (7 prawns per m 2 , with 1 tilapia per m 2 ) treatments in nonaerated earth ponds. Working with earth ponds without aeration, Santos & Valenti (2002) also observed no significant differences among prawn (M. rosenbergii) reared in both monoculture and polyculture at three different densities (2, 4 and 6 prawns per m 2 ), with tilapia (O. niloticus) at 1 fish per m 2 density.…”

“…García-Pérez et al (2000) observed mean values of 294.2 and 276.9 g m -2 for tilapia monoculure and tilapia polyculture with M. rosenbergii, respectively. Santos & Valenti (2002) also reported that prawn (M. rosenbergii) addition to tilapia culture did not significantly affect tilapia yield varying from 344.5±31.5 g m -2 , for tilapia monoculture, to 367.1±93.8 and 385.7±37.2 g m -2 for polyculture. Even with a reduction on tilapia yield, when shrimp was introduced at a density of 5 shrimp per m 2 , it was possible to reach a shrimp yield of 30.55 g m -2 without any additional feed.…”

“…Bessa Junior et al (2012) also did not observe significant differences in FCR for densities of 2 tilapia per m 2 and shrimp at 3, 6, 9, 12 shrimp per m 2 , with increased shrimp stoking density. The FCR was not affected in a tilapia-prawn polyculture, until the addition of 6 prawns per m 2 with 1 tilapia per m 2 (Santos & Valenti, 2002). When feed is provided for tilapia in a polyculture system, competition for food is apparently negligible.…”

“…It is possible that with tilapia density reduced to 1 fish per m 2 , as by Santos & Valenti (2002) and García-Pérez et al (2000) experiments, a density of 5 shrimp per m 2 , would not affect shrimp performance in nonaerated tanks. In aerated tanks, Candido et al (2005) reported a shrimp survival higher than 83%, in a shrimp-tilapia polyculture.…”

Influence of different dietary protein levels and feeding frequencies on growth performance and feed utilization of the Giant freshwater prawn, Macrobrachium rosenbergii with the Nile tilapia, Oreochromus niloticus in polyculture

“…Tilapia and prawn have different food and feeding habits. Dos Santos and Valenti (2002) reported that the polyculture of the freshwater prawn, M. rosenbergii with the Nile tilapia, O. niloticus, did not affect the production of tilapia. It is known that freshwater prawns feed on benthic organisms (Tidwell et al, 1995), detritus and feces (Zimmerman and New, 2000).…”