Phosphorus metabolism in ruminants. 1. Techniques for phosphorus depletion

Abstract

A dietary technique and a parotid saliva replacement technique for depleting ruminants of phosphorus are described. The unilateral parotid depletion technique, involving permanent re-entrant parotid duct catheterization, with phosphorus-free artificial saliva returned to the duct, rapidly depressed blood and ruminal inorganic phosphorus concentrations of animals fed on a low-phosphorus diet. The parotid technique is capable of removing the total extracellular fluid inorganic phosphorus of cattle, goats and sheep in 5-14 h and is of value for creating acute phosphorus deficiencies in adult ruminants. Removal of phosphorus from the ruminant is slower with the dietary technique.