Abstract
Urinary creatinine excretion is considered reasonably constant in the individual animal (Folin, 1905; Aafjes and Groot, 1961; Albin and Clanton, 1966; Hodgen, Erb and Plotka, 1967) and has been used as a reference substance for expressing excretion rate of various urinary metabolites (Butcher and Harris, 1957; Powell, Plough and Baker, 1961, Scommegna and Chattoraj, 1967; Jones and Erb, 1968b). Moreover, creatinine excretion rate has been related to muscle mass of the body (Brody, 1945; Hankins and Howe, 1946; Miller and Biyth, 1952; Lofgreen and Garrett, 1954; Van Niekerk et al., 1963). Since the metabolites of steroids in urine may fluctuate considerably in 24 hr. or less, a simple method is required to express short-term excretion rates. Concentration of substances in a random sample of urine is not a satisfactory measure of excretion rate since urine volume varies widely because of environmental and physiological factors. The purposes of this research were to estimate the excretion rate of creanine in urine and evaluate its use as an index compound for estimating rate of excretion of steroids in urine from sows. Copyright © 1970. American Society of Animal Science . Copyright 1970 by American Society of Animal Science