This study looked at aggression in sows when feeding and how it was influenced by the size of partitions and type of food, wet or dry. Six groups of six sows were each put through various combinations of feeder partitions and wet and dry food. Also each sow in groups of sows were ranked 1 to 6 depending on dominance over the other sows in the group. Sows were each given a week to get used to the feeding set up and then were held for 9 days in each system. At 9:00am each sow was fed 2.5kgs of either dry or wet feed ( 1:6 water to feed ratio). The sows were video taped for an hour, fifteen minutes of feeding and then for 45 minutes afterwards. The video tapes were viewed and researchers took note of times sows bit each other and where they were bit ( head, shoulder, vulva). Also it was noted when pigs left the feeder voluntarily or if they were forced to leave by another sow. The results of the compiled data showed that full length body partitions were the most effective in reducing aggression and biting to the head and shoulders, but full body partitions saw increased biting of the vulva. Wet feed reduced aggression compared to dry feed, possibly because portions were larger and sows were full and didn’t have reason to fight, or because all the sows finished eating at the same time there was less competition for feed. The most aggression was found in the fifteen minutes of feeding, aggression was reduced significantly in the 45 minutes following the feeding period. It was found that sows ranked in the 3rd and 4th spot of dominance suffered the most bites and aggression from other sows. Pigs who were ranked 5th and 6th were bitten less but this can be explained because they spent less time at the feeder. Full body partitions were the most effective but lock ins at the back of the stall could be incorporated to reduce vulva biting. Shoulder length partitions along with wet feed were found to be as effective in reducing aggression as full body partitions.

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