Habitat aridity as a determinant of the trade-off between water conservation and evaporative heat loss in bats.

The maintenance of water balance in arid environments might represent a formidable challenge for Chiroptera, since they have high surface-to-volume ratios. In deserts, bats conserve water, for example, using daily torpor, but they also might experience episodic heat bouts, when they may need to increase total evaporative water loss (TEWL) to thermoregulate. We hypothesized that in bats, habitat aridity and its variability determine a trade-off between water conservation and thermoregulation via evaporative means.

Bilateral ectopic ureters in a male dog with unilateral renal agenesis.

A 1-year-old neutered male mixed-breed dog was evaluated because of signs of urinary incontinence. Retrograde positive contrast urethrocystography and excretory urography with pneumocystography revealed bilateral intramural ectopic ureters and absence of the right kidney. During abdominal exploratory surgery, only the left kidney was located.