Improving the practicality of measuring motivation for food in ruminants

The measurement of strength of motivation is widely used to assess the resources that an animal values by providing an insight into how much work an animal is willing to do to obtain that resource. Animals are trained to perform an operant behaviour to access a resource and are then asked to 'pay a price' to maintain this access. A proven protocol for testing food motivation in ruminants allows unrestricted access to food over 23 hours, meaning that only one animal can be tested at each access prices in each set of apparatus per day. When testing is added to the necessary habituation and training required, motivation experiments can take upwards of four months to complete. As the equipment is generally too expensive to replicate it would be useful if several animals could be tested per day. Therefore, the aim of this investigation was to determine whether shorter periods of testing could differentiate food motivation between animals exposed to different levels of food restriction.