Weekly body weight gain, feed intake, and hemagglutination inhibition (HI) titer in mice fed diets with adequate protein (AP) or very low protein (VLP). A, Change in percentage body weight gain over 3 weeks. B, Weekly feed intake. C, D, Serum HI titers in AP and VLP groups treated with H5-HA, adjuvanted H5-HA, or adjuvant. Data in all 4 panels represent results from 2 experiments (20 mice per group). Values in A and B represent means with standard deviations; in C, each symbol represents an individual mouse from 2 experiments with 10–14 mice per group, and horizontal lines represent mean group values.