The possibility of predicting the sheep voluntary dry matter intake of hays from their rumen degradation characteristics

Abstract

Ability to predict accurately the intake of digestible nutrients by ruminants is of great interest. The feed intake can be limited mainly by the amount of undigested residue remaining in the rumen. Ingested feed disappears from the rumen in two ways: through digestion and through passage. So, forages with easily degraded cell-walls, may promote faster rates of digestion and passage and allow the animal to consume more feed (Hovell et al., 1986). The objective of the present study is to determine the rate and extent of rumen degradation of various hays “in situ” and to evaluate the ability to predict the voluntary intake from these rumen degradation characteristics. Eleven sun-cured hays from three cultivars (alfalfa, red-clover and vetch-cereal), two sown grasslands (grass-clover mixture and mixed grass sward) and six permanent meadows were used to study the relationship between some rumen degradation characteristics and the voluntary dry matter intake (VDMI) by sheep.