Effect of wheat adaptation strategies on rumen parameters and dry matter intake of late lactation dairy cows

Abstract

The effects of a major dietary change on ruminal fluid pH, volatile fatty acid (VFA), lactate and ammonia concentrations, dry matter intake (DMI) and milk yield were measured in 32 dairy cows in late lactation. All cows were initially fed 100% lucerne hay cubes and were then gradually introduced to a diet with wheat comprising 40% of total dry matter (DM) and lucerne hay cubes, the remainder. Wheat was gradually substituted for lucerne via one of four strategies, (1) in six small increments (each 6.7% of total DM) over 6 days (2) in six small increments (each 6.7% of total DM) over 11 days (3) in three large increments (each 13.3% of total DM) over 6 days or (4) in three large increments (ea..