PHYSIOLOGICAL-RESPONSES OF THE COMMON CLOWNFISH, AMPHIPRION OCELLARIS(CUVIER), TO FACTORS RELATED TO PACKAGING AND LONG-DISTANCE TRANSPORTBY AIR

The physiological response of the common clownfish, A. ocellaris, to f actors pertinent to air transportation conditions was studied in three stages: (i) determination of temperature effect and exposure process on oxygen consumption rates; (ii) elucidation of excretion trends of s elected metabolites in simulated packaging experiments, and (iii) prel iminary tolerance studies of some packaging parameters. Temperature si gnificantly affected the metabolic rates of the clownfish. Q(10) value s were relatively constant in fish exposed to sudden changes in temper ature (from 25 degrees C to either 15, 20, 30 or 35 degrees C). Those treated with gradual changes in temperature showed much greater increa ses in oxygen consumption at temperatures above 25 degrees C. The temp erature selected for subsequent experiments was 25 degrees C. Dissolve d oxygen levels of packaging water remained high throughout the 48-h p eriod. Water [H+] and total dissolved and unionized CO2 concentrations changed most significantly during the initial 24 h and then levelled off by 48 h. Similarities in changes of concentrations between these i mply close interaction between the measured variables. The total disso lved NH3 continued to increase with no signs of levelling off. The con centrations of unionized NH3 increased four-fold to 1.4 mu M The excre tion of CO2 decreased linearly at a rate of 150 nmol/g per h while the excretion of NH3 increased at a rate of 97 nmol/g per h. A temperatur e range between 24 and 32 degrees C was found to be necessary for surv ival of the fish with an optimal temperature of 27 degrees C. Clownfis h started to die when the pH of the seawater fell to 6.34 or total dis solved NH3 rose above 0.97 mM ([unionized NH3] = 38.35 mu M). At 15 de grees C, the fish started to die at 20 mm Hg which was twice the oxyge n level at 20 degrees C or above.