“…Other metabolic parameters that tend to be higher or greater in GF animals as compared to CV animals include pH of cecal contents (Thompson and Trexler, 1971), mean intracolonic oxygen pressure (Bornside et al, 1976), pulmonary arteriovenous oxygen values (Schwartz, 1975), plasma levels of some steroids (Einarsson et al, 1973), urinary citrate excretion (Gustafsson, 1948), and fasting blood glucose (Pleasants, 1974). In addition, aortas and portal veins have a higher total calcium content in GF animals (Altura et al, 1975), and the microvasculature is refractory to catecholamines (Gordon et al, 1966;Baez and Gordon, 1971).…”