Milk quality, manufacturing properties and blood biochemical profile from dairy cows fed peas (Pisum sativum L.) as dietary protein supplement

Pea (Pisum sativum L.), a protein-rich legume seed well adapted to many climatic areas and widely used for feed and food, was fed to Italian Friesian breed cows for 16 weeks to assess its effects on milk yield and production, renneting properties and metabolic responses. Cows within each group were assigned to two isonitrogenous and isoenergetic concentrates based on corn plus soybean meal or peas. Individual milk samples were collected from two consecutive milkings, composited, and then analysed for fat, protein, casein and lactose contents and somatic cells count as well as blood and milk urea and milk technological characteristics. Cow blood samples were taken and plasma were analysed for metabolites, biological enzymes, β-hydroxybutyrate (BHBA) and non-esterified fatty acids (NEFA). Peas supplementation had no effects on metabolic blood profile as well as on milk composition traits and clotting aptitude. Milk and blood from cows fed peas indicated a reduction (P<0.05) of their urea concentrations compared to those fed soybean meal. Our findings indicate that peas can replace soybean meal as protein source in diet of dairy cows without unfavourable effects on milk quality and cheesemaking properties.