Effect of supplemental methionine, choline and their combinations on the performance and immune response of broilers.

1. A study was conducted with broilers to find out the effect of addition of methionine (0.0, 1.5, 3.0 and 4.5 g/kg) and choline (0.0, 1000 and 2000 mg/kg) to a basal diet containing crude protein, 221 g/kg, ME, 12.25 MJ/kg, methionine, 3.6 g/kg and choline, 1300 mg/kg. 2. Supplemental levels of methionine and choline were found to be ineffective in improving the growth, food consumption and food conversion efficiency of broilers. 3. However, a higher value for leucocyte migration inhibition was observed in chicks fed on the diet containing 6.5 g/kg methionine and 1300 mg/kg choline, indicating a significantly improved cellular immune response. 4. HI test and ELISA indicated enhanced antibody titres in chicks receiving 3.0 g/kg methionine and 3300 mg/kg choline, showing a significantly better humoral immune response. 5. Methionine and choline should be supplemented at levels higher than the recommended level of BIS for better health and production in chicks.