Respiration of carp under anesthesia induced by mixed bubbling of carbon dioxide and oxygen.

Abstract

Anesthetization of fish by mixed bubbling into the ambient water of carbon dioxide and oxygen is being tried as a method of live transport. To get fundamental information on fish under anesthesia, respiratory parameters were measured with carp before, during and after anesthesia induced by 1:1 mixed bubbling of carbon dioxide and oxygen. During the anesthesia, oxygen content and oxygen saturation of the arterial blood was maintained at levels higher than or equal to the pre-anesthetic ones owing to very high PO2 accompanied with elevated Ht and Hb in the blood, in spite of enormously high PCO2 which ought to reduce the oxygen affinity of the blood. Gill ventilation was also maintained at the pre-anesthetic level due to increased frequency of respiration, notwithstanding its reduced stroke volume. Oxygen consumption was reduced to one-half its pre-anesthetic level, accompanied with a sharp drop of oxygen utilization at the gills.