Exogenous insulin could alter stress response during slaughter in broiler chicken

Abstract

The process of slaughtering animals is known to induce significant stress, which subsequently triggers a wide array of physiological and metabolic alterations. Amongst avian species, this stress often leads to changes in the secretion of various hormones, particularly insulin and cortisol. This study aimed to investigate the role of insulin by administering synthetic insulin during the slaughter of broiler chicken. Fifteen broiler chickens were randomly divided into three groups, comprising a control group receiving subcutaneous saline (s/c saline) and two treatment groups, with one receiving 4 IU of insulin subcutaneously (T1) and the other receiving 8 IU of insulin subcutaneously (T2). The research protocol involved collecting blood samples both prior to and subsequent to the slaughtering process. These blood samples were then analyzed to measure the levels of serum glucose and cortisol, as well as to assess hemoglobin concentration and determine the Heterophil:Lymphocyte (H:L) ratio. The administration of insulin, 30 minutes before the slaughtering process, leads to a significant decrease in serum glucose levels in the treatment groups. In contrast, the hemoglobin levels remained relatively stable, showing no significant changes following insulin administration. Equally significant was the observation that the H:L ratio, which indicates stress in avian species and serum cortisol, exhibited marked reductions after insulin administration. These results strongly suggest that insulin may have a role in reducing stress levels in broiler chickens during the slaughter process. These findings point could contribute to enhanced animal welfare practices in the live bird market.