Nutritive Characterization of Certain Grass Hays in Northern New Mexico

Abstract

Botanical and chemical composition along with nutrient digestibility were studied on five grass hays from north-central New Mexico. Although botanical composition varied widely among the hays, they were similar in most chemical constituents and in digestibility of these constituents. Crude protein was the most variable chemical constituent and was also the most variable component in digestibility among the hays. Digestible protein contents for the hays were closely related to their crude protein percentages. By comparing nutrient composition to nutrient requirements for cattle, an estimate of the feeding value of the hays was obtained. All hays contained sufficient energy and all but one sufficient protein for pregnant cows, but most hays were deficient in these nutrients for lactating cows or growing calves.