Bloat in Cattle. VII. Relation to Amino Acid Composition of Alfalfa as Affected by Maturity

Abstract

The aerial portions of alfalfa plants of different maturities were separated into a nonprotein nitrogen fraction and a water-soluble fraction. The whole plant and each fraction were analyzed for N and for 17 amino acids. The bloating tendency of alfalfa was determined by permitting bloat-susceptible cattle to graze the pasture. Changes in plant maturity during two seasons had little, if any, effect on the amino acid composition of the whole alfalfa plant, nonprotein N fraction, or soluble fraction. The N content of the whole plant and its fractions decreased with increasing maturity. In general, the incidence of bloat also decreased with increasing maturity. It was not possible to establish any clear association between the amino acid content of the aerial portion of the alfalfa plant and stage of maturity or the bloat-provoking ability associated with stage of maturity.