Prophylactic effects of dietary ascorbic acid on oxidative stress indices, physiological and behavioural responses of domestic pigeons exposed to road transport stress

Transport disturbs birds’ welfare and health status which lead to oxidative stress and dietary ascorbic acid mitigates the adverse effects of transport stress. The present study was aimed to evaluate the impacts of ascorbic acid administration on oxidative stress indices, cortisol, H/L ratio, tonic immobility reaction and rectal temperature of pigeons exposed to road transport. A total of 80 clinically healthy pigeons were selected and randomly divided to eight equal groups as follow: (1) Ctrl(–): fed by basal diet and no subjected to transport stress; (2) Ctrl+: fed by the basal diet and subjected to transport stress; (3, 4) 1DBS10 and 1DBS16: received ascorbic acid from 1 day before transport stress at doses of 10 g/100 L and 16 g/100 L of drinking water, respectively; (5, 6) 3DBS10 and 3DBS16: treated with ascorbic acid from 3 consecutive days before transport stress at doses of 10 g/100 L and 16 g/100 L, respectively and (7, 8) 7DBS10 and 7DBS16: received ascorbic acid from 7 consecutive days before the transport at doses 10 g/100 L and 16 g/100 L, respectively. Birds were transported for 3 h over a distance of about 200 km. The total antioxidant capacity, malondialdehyde and cortisol were measured before transport and at 6, 24 and 72 h post‐transportation. The rectal temperature and tunic immobility reactions were recorded. Dietary ascorbic acid led to a decrease in tonic immobility response, hetrophil to lymphocyte ratio, circulating cortisol and total antioxidant capacity, and an increase in circulating malondialdehyde in pigeons exposed to transport stress compare to Ctrl+ group. In conclusion, ascorbic acid administration at dose 16 g/100 L of drinking water from 3 and 7 days before exposure to stress helps attenuate undesirable effects of oxidative stress in pigeons.