An improved grazed class method to estimate species selection and dry matter intake by cows at pasture

Research has recently focused on pasture species intake by ruminants due to their influence on animal product quality. A field-applicable method which investigates species intake and selection, was tested on two dairy cow grazing systems: continuous grazing on a highly-biodiverse pasture (C) and rotational grazing on a moderately-diverse sward (R). In addition to the grazed class method, which evaluates the percentage of grazed dry matter (DM) per species according to the residual height of the plant grazed, further measurements were introduced to quantify DM consumption and selection index per species. Six and four representative species were studied in the C and R systems respectively. We found an exponential regression between the presence of a species and its contribution to the cattle’s daily intake (P