Effects of Replacing Duckweed with Red Corn Meal and Rice Bran on Growth Performance of Local Chicken in Semi-Confined and Confined Systems

Incorporating duckweed into poultry diets can improve feed efficiency and growth rate. However, its effectiveness as a replacement for traditional feeds such as red corn meal or rice bran remains less explored. The present study aimed to evaluate the feed intake, average daily gain (ADG), and feed conversion ratio (FCR) in local chickens reared under confined and semi-confined systems. The experiment was conducted at the campus of Svay Rieng University, Svay Rieng Province, Cambodia, from June to August 2024. The present study consisted of two factors. The first factor was the rearing system, including semi-confined and confined systems, and the second factor was the diet, with four treatments. A total of 120 local chickens, 35 days old, with an average initial body weight of 300 grams, were arranged in a 2 × 4 factorial layout using a completely randomized design within eight treatments and three replications. The first group included 5% duckweed, 22% commercial feed, 20% red corn meal, 52.5% rice bran, and 0.5% premix/salt (T1). The second group consisted of 10% duckweed, 19% commercial feed, 20% red corn meal, 50.5% rice bran, and 0.5% premix/salt (T2). The third group had 15% duckweed, 16% commercial feed, 20% red corn meal, 48.5% rice bran, and 0.5% premix/salt (T3), and the fourth group included 20% duckweed, 13% commercial feed, 20% red corn meal, 46.5% rice bran, and 0.5% premix/salt (T4). There were no significant interactions between four diets and two raising systems for feed intake, ADG, and FCR in the chickens, except for the crude fiber intake. However, significant differences were observed in T1 and T2 compared to T4 regarding feed intake and ADG, with a tendency toward improved FCR for chickens fed T3 compared to T4 and those raised under the confined system. The growth performance in chickens raised under the confined system was higher than that of chickens raised under the semi-confined system. The present results indicated that using duckweed at 15% mixed with other ingredients led to higher feed intake, higher ADG, and improved FCR, even when chickens were raised in a confined or semi-confined system. Keywords: Commercial feed, Confined system, Duckweed, Performance, Red corn