Response of adult rats to lysine supplementation

The response of adult rats to wheat flour protein fortified by addition of lysine was studied by utilizing the relative protein value (RPV) compared to non-fortified wheat flour. Lactalbumin was used as a standard protein. Fortification of wheat flour by 0.3% lysine resulted in better growth of rats when fed at 6% protein level. However, no significant difference was observed in the growth of rats fed non-fortified or fortified wheat flour at 4% or 2% protein level. The relative nutritive value (RNV) of supplemented wheat flour protein is higher than that of the non-supplemented when change in body weight or change in body water are used as response parameters. When the dietary protein is provided at maintenance or below maintenance levels, lysine is not limiting. Therefore, supplementation of wheat flour protein with lysine did not result in any better growth response. When protein is provided at levels above maintenance requirements lysine is limiting and better growth was achieved by lysine supplementation to wheat flour protein.