Selection of forage species by dairy cattle on complex Sicilian pasture

Abstract

This study examined the selective foraging behaviour of dairy cattle on very complex pastures as a part of a larger study on the influence of diet upon cheese flavour [Selective grazing on Sicilian pasture by cattle and effects on Ragusano cheese, Ph.D. dissertation, Cornell University, Ithaca, NY, 2003]. Sicilian pastures can contain over 100 plant species belonging to over 25 families, although not all of these species may occur in a single pasture. A grazing study was conducted on a farm with a group of 13 lactating Friesian cows. Milk was used to make cheeses that were evaluated in a separate study. Pasture composition and selection of plant species by cows were studied in the years 1999 and 2000. Qualities of mixed selected forage were uniformly very high and did not vary greatly over season and years. While pasture composition varied between years, animal selection was highly correlated with species incidence ( r=0.83). Animal choices tend to follow occurrence. A few species remained uneaten including Carduus (thistle) and Biscutella. The dominant species consumed belonged to the plant families Asteraceae (Compositae), Cruciferae, Malvaceae and Fabaceae. This information was used in a larger study to relate pasture species to flavour of cheese.