Effect of increasing valine level in the diet on performance, egg quality and serum components in laying quails

One of the branched-chain amino acids, valine, is regarded as fifty limiting amino acid for birds fed with based on corn-soybean meal. It also plays a crucial role in performance, protein and lipid metabolism, energy stability, cell function and immunity. Increasing valine level decreased egg weight and egg mass. At the same time, the albumen index and the Haugh unit decreased. Serum glucose and triglyceride levels reduced with increasing valine level. Additionally, it decreased erythrocyte and haematocrit, but increased white blood cell, neutrophil and lymphocyte counts.