Effect of flavour change on food intake by horses

Horses almost invariably consume only small quantities of food when it is presented for the first time (van den Berg et al., 2015a). This cautious sampling of new food types is referred to as neophobia ("fear of new") and has been suggested as an innate herbivore survival mechanism for avoiding the over-consumption of toxic plants in the wild (Provenza and Balph, 1988). While feed neophobia has been anecdotally described in horses as "fussy eaters" recent studies (van den Berg et al., 2015a, 2015b) suggest that similar responses occur in many species. Food flavours are commonly used by the commercial horse feed industry with the objective to overcome feed neophobia, but there are limited studies that have investigated the acceptance of flavours. Although, Goodwin et al. (2005) has shown that in multiple choice trials (short term) horses can respond to sensory variety in concentrate diets that differ in flavours (odour and caloric taste) and/or formulations (nutrients), selecting from preferred and less preferred foods. At present it is unclear how horses respond to non-nutritive flavour changes over a longer term (when a single diet is presented). Therefore, as part of a larger study the responses of horses to flavour (odour) change on diet intake by horses were examined.