Sinking Feed Efficiency in Growth Performance, Feed Conversion Ratio (FCR) and Yield of Tilapia (Oreochromis niloticus) at Different Stocking Densities

Abstract

The efficiency of feed is considered as one of the most crucial factors that affects the growth performance, feed conversion ratio and yield as well. The study was aimed to compare the growth parameters of tilapia at different stocking densities to detect the efficiency of sinking feed assessing the growth trends at various sampling stages. To evaluate the comparative yield, the study was carried out in twelve concrete tanks under an outdoor laboratory shed. Tilapia (Oreochromis niloticus) fry was released at the rate of 8 fry per tank as per the recommended stocking density of 320 fishes/decimal and 4 fry per tank equivalent to the stocking density of 160 fishes/decimal in intensive and semi-intensive aquaculture system, respectively. To evaluate the growth trends sinking feed was used for feeding the fish during the experimental period for T1 (Intensive) and T2 (Semi-intensive), respectively. The feed was supplied in each with three replications at the rate of 20%, 15%, and 10% of the body weight of fish, respectively. The daily ration of feed was delivered to fish dividing into two parts daily. Aeration facilities using air stone aerator were installed for 24 hours. To assume the consecutive growth trends, weight of fish was recorded in 3 days interval to have better understanding on the yield performance in relation to the feed conversion ratio (FCR). Water quality parameters i.e., temperature and dissolved oxygen (DO) were recorded two times daily. The final weight gains of fish were 133.77±5.65 gm and 50.70±2.40 gm for T1 and T2, respectively. The mean percent weight gain of tilapia was higher in T1 (1127.25±0.00) than T2 (518.51±0.00 gm). Feed conversion ratio (FCR) in T1 and T2 were 1.97±0.11 and 1.70±0.07, respectively. The specific growth rates (SGR) of tilapia in T1 4.90±3.03 and 4.78±3.83 considering the data at the beginning and the end of the production cycle, respectively. Higher total production was obtained in T1 (1070.19 gm) than T2 (610.00 gm) with 100% survival in both the treatments. The present study reveals that, the efficiency of sinking feed was higher in T1 than T2 and farmers might be suggested to practice tank-based intensive aquaculture system to get higher production in a short period of time.