Effects of hypertonic sodium chloride injection on body water distribution in Ducks ... Gulls ... and roosters.

Isotope and dye estimates were made of body fluid compartment sizes in White Leghorn roosters, Glaucous-winged gulls, and in groups of Pekin ducks which were raised on either fresh water or regimes of hypertonic NaCl solution. The gulls and both groups of ducks were observed to have plasma (T-1824 dye) and total body water (H₂³O) volumes larger than thoseof the roosters, whereas the reverse was true for Br⁸² space (extracellular fluid; ECF) measurements. Salt fed ducks showed smaller, but insignificantly different compartment sizes (% body weights) when compared to fresh water raised ducks. The effects of an intravenous injection of hypertonic NaCl on the distribution of body water were compared among birds which differed in their capacity for renal and extra-renal salt elimination. In those birds (gulls, salt water ducks, and fresh water ducks with functional salt glands) which exhibited extra-renal salt secretion, the increase in ECF was significantly greater in response to the intravenous injection of hypertonic NaCl than in those birds (roosters and non-secreting fresh water ducks) which did not utilize the salt glands. The relative amounts and concentrations of the salt load removed by renal and extra-renal routes of elimination were compared. Birds with actively secreting nasal glands voided a major equivalent of the injected NaCl as solutions hypertonic to plasma NaCl levels. Renally eliminated NaCl represented a much smaller portion of the load and was in all cases hypo- or isotonic with plasma ion levels. Isotopically labelled Na²² CI administered concomitantly with the salt load in several of the test birds revealed that a large portion of the labelled sodium chloride was removed by the nasal glands and kidneys before there was equilibration of the injected load with extravascular compartments. A preliminary report is made on the composition and possible source of an excess eye secretion observed in the rearing of saline fed Pekin ducks. The enlarged Harderian glands of these birds were implicated as the source of a fluid several fold hyperkalemic to plasma ion concentrations. The secreted fluid was observed to accumulate and encrust the feathers below the inner canthus of the eye.Science, Faculty ofZoology, Department ofGraduat