Biswas, A., Mohan, J., Sastry, K.V.H. and Tyagi, J.S. 2008. Effect of higher levels of dietary vitamin E on performance and immune responses in growing Japanese quail. J. Appl. Anim. Res., 33: 61–64. To study the effect of increasing dietary vitamin E (VE) on performance and immune response, 240 day old chicks were randomly selected and divided into 12 groups with 20 chicks in each group (3 dietary treatments × 4 replicates). The basal diet contained 15 IU VE/kg and the two experimental diets were supplemented with 150 IU and 300 IU VE/kg. Body weight gain, feed intake, feed conversion ratio and mortality were not affected by VE supplementation. Antibody titres, response to intradermally injected phytohaemagglutinin (PHA) and the relative weights of the bursa of Fabricius and thymus were significantly (P<0.05) higher after feeding the two VE-supplemented diets. It is concluded that VE supplementation improved immune response but not performance in growing Japanese quail.