Replacing fish meal with chicken offal silage in commercial Oreochromis niloticus (L.) feed

Four isocaloric isonitrogenous rations containing various levels (0,10, 15 and 20%) of chicken offal silage as a replacement for fish meal were fed to three replicate groups of Oreochromis niloticus (L.) fingerlings with a mean initial weight of 10.8g. Ten fish per tank were tested for 5 weeks in 40‐1 aquaria. The aquaria were put together in a flow‐through system utilizing underground water (24 ± 3°C). Weight gain, feed conversion, protein efficiency ratio and proximate body composition did not vary significantly between treatments. These results indicate that, on an isocaloric/ isonitrogenous basis, chicken offal silage can make up as much as 20% of O. niloticus commercial feed as a replacement for fish meal without any effect on growth or proximate body composition under the experimental conditions.