Effect of Polyculture on Survival Rates and Body Composition of Fish Cultured in Rice Fields

Abstract

The study was conducted for the period from 6/7/2022 to 7/12/2022, with the aim of knowing the effect of farming different species of fish in rice fields on survival rates and body composition: moisture, protein, fat, carbohydrates, ash and fiber. The land was divided into four fields planted with rice, Oryza sativa, the area of each field was 100 m2 with dimensions of 10 m × 10 m. After the height of the rice reached 20 cm, the immersion phase began, after which two species of fish were released: the common carp Cyprinus carpio and the grass carp Ctenopharyngodon idellus inside Rice fields, four experimental treatments were used that were cultured with rice and fish at a density of 100 fish/field, with an average initial weight of 100 ± 5 g/fish. The first treatment included the culture of common carp alone, in the second treatment, the grass carp was cultured alone, while in the third treatment the common and grass carp were cultured together by 50 fish each, and in the fourth treatment, the common and grass carp were cultured by 75 and 25 fish, respectively. The results of the statistical analysis of the body composition of common carp and grass carp showed significant differences among the treatments, the T1 recorded the highest percentage of moisture amounting to 74.74%, while the highest percentage of moisture was recorded in T3 which amounted to 73.05%, T3 recorded the highest percentage of protein and amounted to 23.95%, followed by T2 which reached 22.09%, T4 recorded the highest percentage of fat for common carp and grass carp, reaching 5.96% and 5.09%, respectively. With regard to ash, T3 recorded the highest percentage, amounting to 1.36% for common carp fish, while T2 recorded the highest percentage of ash, amounting to 1.52% for grass carp fish. As for carbohydrates, T3 recorded the highest percentage and amounted to 0.22% for common carp, while T2 recorded the highest percentage it was 0.32% for grass carp. With regard to fibers, T4 recorded the highest percentage of 0.34% for common carp, while T2 recorded the highest percentage of 0.15% for grass carp.