Thirty mid lactating Holstein cows (159 DIM) were used to evaluate the substitution of ground corn with gluten feed (FGM-21) in total mixed diets containing corn silage as the main forage and citrus pulp as part of the energy source. Treatments were: no FGM-21 and 20% ground corn in total feed DM (FGM 0), 10% FGM-21 and 10% ground corn in total feed DM (FGM 10), and no corn and 20% FGM-21 in total feed DM (FGM 20). The parameters evaluated were: dry matter intake, milk yield and composition, milk urea N concentration, blood parameters and body condition score. Cows were randomly assigned in ten 3 × 3 Latin Squares, according to milk yield, days in lactation and parity. Treatments did not affect the daily dry matter intake (DMI) (21.19 kg/d), milk yield (24.88 kg/d), FCM yield (25.34 kg/d), milk fat content (3.62%), and milk total solids (11.86%). Inclusion of corn gluten feed affected milk protein, lactose and urea concentrations.
byproducts; fibrous feeds; lactating cows; milk production and composition; ruminants
