标题：The Feasibility of Monoculture and Polyculture of Striped Catfish and Nile Tilapia in Different Proportions and Their Effects on Growth Performance, Productivity, and Financial Revenue
摘要：Cultivation of species of high growth rates is a key achievement of sustainable aquaculture development, with the aim of increasing animal protein per capita, maintaining food security and preserving freshwater usage. The present study was conducted to evaluate the feasibility of monoculture and polyculture of striped catfish, Pangasianodon hypophthalmus, and Nile tilapia, Oreochromis niloticus, in different proportions and their effect on growth performance, survival, productivity, feed utilization, body composition, and financial revenue. Five experimental treatments were designed as follows: monoculture of striped catfish (100%), Nile tilapia (100%) and polyculture in different proportions of striped catfish and Nile tilapia (25%:75%; 50%:50%; 75%:25%, respectively), each in three replicates. The fish feeding regime consisted of isonitrogenous (307.80 g kg−1) and isocaloric (19.27-kJ g−1) diets for 14 weeks. The results revealed that the highest growth performance, feed utilization, survival of striped catfish were obtained in monoculture, followed by polyculture of striped catfish and Nile tilapia (in low proportions) (75%:25%). The total production per m3 reached 5.41 kg m−3 in the monoculture of striped catfish, this production decreased in polyculture by 52%, 46% and 23% with 25%; 50%; 75% of striped catfish. The gross margin significantly increased, in case of striped catfish farmed in monoculture, compared to other polyculture proportions. While the gross margin per m−3 of water was 6, 0.5, 1 and 3 $ in monoculture and different polyculture proportions, respectively. Moreover, the feed cost per kilogram of protein gain significantly decreased in the monoculture of striped catfish compared to other polyculture treatments. The growth performance and survival of tilapia showed no significant difference among different treatments. In addition, the proximate chemical composition did not differ in respect to species in different studied treatments. Monoculture of striped catfish is recommended to achieve high production and improve financial revenue per water unit (m−3), for better sustainable development of aquaculture.
