Ameliorating effect of melatonin on colonic temperature and erythrocyte osmotic fragility of Japanese quails (Coturnix coturnix japonica) transported by road

Experiments were performed with the aim of determining the effect of 2-h road transportation and the administration of melatonin on colonic temperature (CT) and erythrocyte osmotic fragility of 90 eight-week-old Japanese broiler quails. The birds were randomly divided into two groups of 45 birds each: control, not administered with melatonin; and mel-treated group, administered with melatonin at a dose rate of 0.5 mg/kg body weight. Thereafter, the quails were transported for 2 hours. Erythrocyte osmotic fragility was analysed before transportation, immediately after transportation and on the third day of post-transportation period. The ambient temperature (AT) and relative humidity (RH) recorded inside the vehicle during transportation fluctuated between 29.5 to 37.6 degrees C and 55.6 to 74.7%, respectively. The CT values recorded 30 min, 1 h and 2 h of transportation in the control quails were significantly (P < 0.05) higher than the values obtained in mel-treated quails. The mean corpuscular fragility (50%), minimum (20%) and maximum (80%) fragility values recorded in the control quails after the transportation were significantly (P < 0.05) greater than the corresponding values obtained in mel-treated quails. They demonstrated an increase in haemolysis on each point of the fragility curve, compared to the values obtained in the mel-treated quails. In conclusion, 2-h of road transportation during the hot-humid season resulted in hyperthermia and haemolysis. The administration of melatonin to quails prior to transportation reduced the risk of adverse effects of transportation procedures and heat stress on CT and fragility of erythrocytes in quails.