AJP - Regulatory, Integrative and Comparative Physiology, Vol 247, Issue 2 246-R249, Copyright © 1984 by American Physiological Society
Saline acclimation and water and sodium transport across avian small intestine
J. R. Roberts and M. R. Hughes
The uptake of sodium and water across everted sacs of the jejunum and ileum
of Pekin ducklings, nestling Glaucous-winged gulls, and adult Japanese
quail was measured in both freshwater- and saltwater-acclimated birds to
assess the importance of the avian small intestine in salt and water
balance after a salt load. The jejunum and ileum together were divided into
segments I-V in ducklings and gulls and segments I-IV in Japanese quail.
Acclimation to sodium chloride solutions increased the uptake of sodium and
water, per unit dry weight of tissue, across segments II and IV in larger
ducklings, although no significant differences were observed in smaller
ducklings. Sodium and water transport were significantly greater across the
posterior region of the small intestine of saltwater-acclimated gulls. In
Japanese quail acclimated to sodium chloride solutions, mean values for
sodium and water uptake were decreased, compared with
fresh-water-acclimated birds, but were not statistically significantly
different. Increased uptake of water and sodium after saline acclimation
appears to be correlated with the presence of functional salt glands.
