Growth performance of bonylip barb Osteochilus vittatus (Valenciennes, 1842) fed on combination of Lemna (Lemna perpussila Torr) and commercial diet

Abstract
Bonylip barb (Osteochilus vittatus Valenciennes, 1842) is a native fish of Indonesia's inland waters which has become a cultivated fish commodity. However, production tends to decrease due to high feed costs. The alternative feed types need to be found to anticipate the problem. Lemna perpusilla Torr is one of macrophytes plant which potentially used as an alternative feed due to high protein content. This study aims to evaluate the growth performance of fish fed with a combination of Lemna and commercial feed. As much of each 14 fishes were rearing in a 45x45x40 cm3 aquarium and fed for 84 days or 12 weeks. There are 5 combinations of feed, i.e feed A (100% commercial feed), B (75% commercial feed + 25% Lemna), C (50% commercial feed + 50% Lemna), D (25% commercial feed + 75% Lemna), and E (100% Lemna). The fishes were fed by commercial feed as much as 3% of the total fish, while administering Lemna at 30% of body weight. Growth performances were measured i.e standard and total length, absolute growth, specific growth rate and survival rate. The results showed that fish was able to growth using combination of commercial feed and Lemna. Data analysis was conducted descriptively that showed that fish fed by feed C (50% commercial feed + 50% Lemna) produced the highest length and weight, absolute growth and specific growth rate compared to other treatments. The highest survival rate was at fish fed by feed E (100% Lemna). The use of Lemna as an alternative feed is expected to reduce dependence on commercial feed.