Feeding Behaviour in Group-Housed Growing-Finishing Pigs and Its Relationship with Growth and Feed Efficiency.

Feed consumption and feeding patterns influence the individual feed efficiency in group-housed livestock species. Using the meal as the unit of feeding behaviour, the main objectives of this research were to identify feeding behaviour () traits that may indicate an individual's rank within the social hierarchy or its level of dominance among pen mates and to assess the relationship between growth and feed efficiency with the identified traits, as well as those describing individual feed consumption patterns. Data from 5516 pigs during the fattening period were used. Pens were equipped with an automatic concentrate feeder that recorded individual feed intake, time spent at the feeder, and body weight at each visit. A meal criterion was established. Then, different FB traits were computed: number of meals, number of visits to complete a meal, occupation time to complete a meal, time between first and last visit within a meal, feeding rate, feeding rate to complete a meal, and interval between meals. Social ranking () traits were also calculated: position/order in which each animal accessed the feeder, ratio of visits to the feeder during preferred times, distribution among the cage mates of the total daily feed, number of visits, number of meals, and occupation time. Pigs that eat more and faster tend to have a poorer feed efficiency and higher final weight. Animals that eat more, more times, and occupy the feeder longer, eat mainly in the preferred period. They could be considered dominant, while others have to adapt their feeding schedules to off-peak times.