This trial was run at Estación Experiment Agropecuária of INTA (EEA-INTA, Rafaela), Argentina. Thirty-two high producing Hostein-Argentina dairy cows were used in early lactation, aiming to evaluate blood parameters at two levels of protected fat (0 and 400 g/cow/day) and two types of alfalfa (fresh or haylage). All cows were submitted to a pre-trial period of fifteen day in two groups: with and without fat supplementation. The animals, post-partum, were allocated to paddocks with green or pre-dried alfalfa, comprising, then, four experimental treatments. A completely randomized design with a 2x2 factorial, using days post-partum and lactation order as covariates, was used. The statistical analysis was performed by using the analysis of variance and F-test. There were no differences among experimental treatments.
alfalfa grazing; hydrogenated fat fish; blood parameters; lactating cows
