Studies on Sodium Bentonite in Ruminant Diets Containing Urea

Abstract

Sodium bentonite is an inert colloidal clay of volcanic origin and is composed primarily of mineral montmorillonite, which is a hydrated form of aluminum silicate. It is able to absorb much water and certain cations and appears to improve the physical nature of pelleted feeds. Jordan (1953) found that bentonite improved feed intake and gains of sheep, but these effects were not consistent (Jordan, 1954). Erwin, Elam and Dyer (1957) found that bentonite apparently, but not significantly, improved the performance of steers fed a fattening diet. Because of its great adsorptive capacity for water and certain cations, it was postulated that it might improve the utilization of ruminant rations containing urea. The following experiments were conducted to study this possibility. Trial 1. Digestibility and Nitrogen Retention. Sixteen adult wethers averaging 37 kg. were allotted at random into four treatment groups for the determination of digestibility and nitrogen retention. Diets 1 and 2 (table 1) were each fed with and without 2% sodium bentonite.