Faba bean in dairy cow diet: effect on milk production and quality.

Two consecutive trials were carried out to test flaked faba beans as a partial substitute for soybean meal (SBM) in the diet of Reggiana breed dairy cows. In both trials a “Control” concentrate (12% dehulled SBM) was compared to a “Faba” concentrate (7.5% dehulled SBM; 10% flaked faba beans). Forages fed to animals included hay (mixed grass and alfalfa) plus green mixed grass in trial 1, hay only in trial 2. Concentrate intake, faecal scores, milk yield and quality were similar between feeding groups. The milk urea content was lower in the “Faba” group (“Control” vs “Faba”: 34.6 vs 32.9 mg/dl in trial 1, P<0.1; 27.4 vs 23.4 mg/dl in trial 2, P<0.01). The plasma urea was different only in trial 2 (“Control” vs “Faba”: 3.9 vs 3.0 mmol/l,; P<0.01). The inclusion of faba beans within the allowed limit of the Parmigiano-Reggiano Consortium for diet formulation could represent a feasible opportunity for a partial substitution of SBM.