Recovery of earth-pond-reared Pelteobagrus fulvidraco from transport stress in acclimatization of laboratory system

Earth-pond-reared adult yellow catfish(Pelteobagrus fulvidraco R.) were transported to the indoor laboratory recycle system.Feeding and responsiveness to daily management,blood cortisol and glucose,percentage and phagocytic function of circulating leukocytes of the fish were monitored immediately after transport(day 0) and in acclimatization of the laboratory system for a period of 35 days.Cessation of feeding was apparent during the first 4 to 7 days after transport.All fish resumed feeding by day 8 and adapted to daily management by day 15.Blood cortisol and glucose concentrations were significantly high at day 0,1,2 and 3.Elevated blood cortisol and glucose significantly decreased by day 7 and maintained at low levels at day 21,28 and 35.No significant differences were found in circulating erythrocyte numbers.Compared to values of each parameter for circulating leukocytes at day 21,28 and 35,lymphocytopenia was found at day 3 and 7,neutrophilia was detected at day 0,1,2 and 3,significantly decreased phagocytosis and phagocytic index of peripheral leukocytes were found at day 7 and 14.The results of the present study indicate(1) that transport induced characteristic stress responses in the adult yellow catfish,(2) that transport resulted in significant alterations in the percentage of circulating lymphocytes and neutrophils and suppression in the phagocytic function of circulating leukocytes in the adult yellow catfish,(3) that a minimum of three weeks needed for the earth-pond-reared adult yellow catfish to completely recover from transport stress in acclimatization of the laboratory system.