Effect of chronic tracheal bypass implant on the nasal breathing in sheep.

Abstract Three sexually matured Rambouillet ewes were surgically implanted with a reversible, tracheal bypass canula. A total of seven trials were made on three resting, unanesthetized sheep in standing position. The ambient temperature was kept constant at 18°C in order that any change in nostril temperature could not be attributed to any fluctuation of this environmental temperature. In all trials, the nostril temperature increased (6°c) when the animal was placed on tracheal (bypassed) breathing and it decreased when the sheep was changed to normal nasal breathing. This paper describes a procedure to study the effects of prolonged interruption of normal nasal breathing.