Do cattle exhibit a preference for white clover?

Attaining a predictable and stable composition of white clover in pasture is affected by selective grazing and inter-species plant competition. This paper reports an experiment which demonstrates that when given a free choice between monocultures of ryegrass and white clover, cattle did not selectively graze only clover but chose a mixed diet. Ten young heifers were stocked for 3 weeks on 2 ha, comprised of adjacent 1-ha monocultures of each of ryegrass and white clover. Animals were given 1 week to adjust to the spatial separation and then on 2 consecutive days in each of 2 consecutive weeks, cattle were observed at 10-minute intervals during daylight hours. Behaviour (grazing or not) and location (ryegrass or white clover) were recorded. This procedure was conducted in December, February and May to assess seasonal variation in the species preference. At each occasion cattle choose a mixed diet by eating both ryegrass and white clover, but their preference for white clover changed with season. In February they exhibited a partial preference for white clover, by spending approximately 65% of grazing time on white clover and 35% on ryegrass. In December and May the partial preference for white clover was lower, with cattle allocating approximately 47% of grazing time to white clover and 53% to ryegrass. Results are discussed in relation to the extent of preference for white clover when limitations to selection are removed and how this information could be used to enhance white clover proportion in the diet to better match animal preference. Keywords: diet selection, grazing behaviour, perennial ryegrass, preference, Trifolium repens L.