OBSERVATIONS OF SHEEP FORAGING IN FAMILIAR AND UNFAMILIAR ENVIRONMENTS - FAMILIARITY WITH THE ENVIRONMENT INFLUENCES DIET SELECTION

We determined if familiarity with a pasture decreased the importance o f social interactions in food selection and choice of foraging locatio n by lambs with different dietary preferences. Lambs in three treatmen ts (18 lambs per treatment) were reared separately for 2 months and ex posed daily to a 1-ha experimental pasture (Treatment 1), to a 0.5-ha pasture with similar forage species to those in the 1-ha experimental pasture (Treatment 2), or reared in confinement and not allowed to gra ze (Treatment 3). Half of the lambs in each treatment were fed mile (S orghum bicolor) and half were fed wheat (Triticum aestivum) daily for 2 months to condition preferences for mile and wheat, respectively. Du ring testing, subgroups of three lambs that were conditioned to prefer mile and three that were conditioned to prefer wheat (three subgroups per treatment) were exposed simultaneously to the 1-ha experimental p asture to determine if social influences affected food selection when mile and wheat were placed at opposite ends of the pasture (100 m apar t). We found: (1) subgroups of lambs familiar with the pasture typical ly consumed different foods, depending on whether they preferred mile or wheat; (2) subgroups of lambs naive to the pasture typically forage d together on the same food; (3) preferences for either mile or wheat persisted for animals familiar with the experimental pasture, whereas lambs naive to the pasture acquired preferences for both foods. Thus, these results suggest social factors can override food preferences in a novel environment, but food preferences may be more influential in f ood selection in a familiar environment.