Serum electrolyte concentrations in Sinclair(S-1) miniature swine from 1 through 36 months of age.

Venous blood samples were collected monthly from 60 male and 60 female Sinclair(S-1) miniature swine from 1 through 36 months of age. The rate of serum urea nitrogen concentration decreased instantaneously for females and increased instantaneously for males as described in the equation y = aebt. Serum creatinine concentration decreased through 20 months of age and increased from 20 through 36 months of age. Serum calcium, inorganic phosphorus, potassium and sodium concentrations decreased instantaneously through 36 months of age. From 14 through 36 months of age, males had a greater mean serum urea nitrogen concentration than did females.