The effect of betaine supplementation on performance of laying hens in the tropical climate during the starting period

Abstract

The study investigated the effects of dietary betaine on the growth performance of laying hens in a tropical climate during the starting period. In total, 192 laying hens strain Lohmann aged three weeks were assigned to four dietary treatments, each consisting of six replicates of eight birds. The dietary treatments included a basal diet (T0) and a basal diet supplemented with betaine at 6 mg/kg (T1), 12 mg/kg (T2), 18 mg/kg (T3). The treatments lasted for eight weeks. Temperature and relative humidity were measured with Hobo-U12, while the wet-bulb temperature was measured using Lutron HT-3027SD. The effect of betaine was not consistent where T3 decreased feed intake (FI) in week 2 but increased FI in weeks 4 and 5. Furthermore, T2 showed higher FI in weeks 6 and 7 than T0 (p<0.05). Accordingly, T2 and T3 led to lower weight gain in week 2, but they compensated with higher weight gain in week 4 when ambient temperature above 30°C occurred for 42 hours in a week. Overall, weight gain and body weight in week 8 was not affected by the treatment. It is concluded that the effect of betaine was more apparent when the birds were exposed to high ambient temperature.