Role of differential food treatment on hypothalamic NPY expression and migratory phenology of redheaded bunting ( <i>Emberiza bruniceps</i> )

The present study explores the effect of differential food treatment on the migratory phenology of redheaded bunting (<i>Emberiza bruniceps</i>). Birds were divided into four groups (<i>N</i> = 10 each) on the basis of the food provided. Group I was fed with seeds of <i>Setaria italica</i> (kakuni), while group II was provided with protein-rich diet (combination of; 3 parts egg white and 1 part kakuni seeds). Likewise, group III birds received fat-rich food (i.e. 3 parts sesame seeds and 1 part kakuni seeds). Birds in group IV were provided with all three food items mentioned above separately. The experiment continued until the appearance of 7 cycles of <i>zugunruhe</i>. The results reveal a significant impact of food on locomotor activity and food intake behavior of birds, although the physiological response as demonstrated by a gain in body mass, fat score, and gonadal recrudescence was mainly influenced by the LHS. Besides the behavioral and physiological responses, the hypothalamic expression of neuropeptide Y (NPY) in infundibular complex (INc) was significantly high for group IV, highlighting the importance of "variety" in food intake. Thus, the present study suggests a significant role of food in influencing seasonal responses via hypothalamic NPY stimulation.