Rearing Rabbits Over Earthen Fish Ponds in Rwanda: Effects on Water and Sediment Quality, Growth, and Production of Nile Tilapia Oreochromis niloticus

Abstract

Nine earthen ponds of 400 m² each, were stocked with 800 mixed sex Nile tilapia Oreochromis niloticus fingerlings (14 g mean weight stocked at 2 fish/m⁻²) and fertilized with rabbit droppings from rabbits reared over fish ponds and stocked at three different densities: T1 = one, T2 = two, and T4 = four rabbits per 100 m² of pond. After 152 days, results from this integrated rabbit/fish system showed: 1) increasing nutrient content of all ponds in the three treatments except for nitrates, which decreased with time and, 2) good water quality in terms of pH, dissolved oxygen, and turbidity. Fish mean weight at harvest and fish yield were higher in ponds fertilized by the highest rabbit stocking rate: 42.32 g and 6.35 ± 1.0 kg/are, respectively (1 are = 100 m²).

Keywords:

• Rabbit survival
• water quality
• pond soil quality
• fish production

Acknowledgments

This work is the first part of an ongoing PhD research funded by the Nile Basin Initiative (NBI-ATP) to whom I would like to convey my gratitude for assistance.