Diet supplied with L‐lysine and L‐arginine during chronic stress of high stock density normalizes growth of broilers

The effects of fortifying a diet with L‐lysine HCl (Lys) and L‐arginine (Arg) in broilers housed under conditions of high stock density, were studied in an experiment that measured bodyweight, feed intake, feed conversion, body temperature, serum protein, immune parameters and neutrophils. A diet fortified with Lys and Arg increased bodyweight gain in broilers housed under high stock density conditions, but not in normally housed controls. The diet fortified with Lys and Arg decreased the feed conversion ratio and abdominal fat, as compared to the effects of a control diet, without regard to housing conditions. No effects of amino acid fortification or stock density on body temperature, serum protein or immune parameters were recorded. The results indicate that an increase in the dietary supply of Lys and Arg is beneficial to broilers during stressful conditions of high stock density, potentially contributing to an enhancement of animal welfare in broiler farms.