Effects of Ingested Soil on Ration Utilization by Dairy Cows

Abstract

Six nonpregnant, nonlactating Holstein cows were fed 3.6 kg concentrate, hay ad libitum, and 0, 450, or 900 g red clay subsoil daily in two 3 × 3 Latin squares. Effects of added soil on apparent digestibility were increases of 20 and 19% for ether extract, decreases of 5 and 9% for dry matter and 2 and 6% for protein, and no effect for organic matter, crude fiber, nitrogen-free extract, and combustible energy. Apparent absorption of potassium was reduced 12 and 25% by increasing soil intake, but absorptions of magnesium, calcium, and phosphorus were not altered. These results indicate that amounts of soil which are likely to be consumed under normal and sparse grazing would not have an important effect on utilization of most major dietary nutrients. © 1977, American Dairy Science Association. All rights reserved.