Abstract
Animal variation in social dominance within a herd has been shown to be associated with performance, feed efficiency and animal well-being. The objective of this study was to quantify disruptive feeding events in cattle fed a high-grain diet. Crossbred steers (n = 85) housed in a pen with GrowSafe bunks were used in this study. An algorithm was developed to quantify displacement events defined as an animal being displaced by another within 5 sec. These feed bunk displacement events were further separated into either displacer events or displacee events. A displacer event was defined as an animal displacing another (aggressive). A displacee event was defined as an animal being displaced (submissive). The displacer events as a proportion of total displacement events were used to classify animals as aggressive versus submissive (±0.5 SD). Animals with fewer displacer events as a proportion of total displacement events (submissive < 0.5 SD) had greater (P < 0.05) frequency and duration of bunk visit events and head down duration than the animals who initiated more displacer events as a total of displacement events (aggressive > 0.5 SD). Additionally, submissive animals also had a slower (P < 0.05) bunk visit eating rate than aggressive animals. The results of this initial analysis found that due to the associations between feed bunk displacements and feeding behavior, there may be potential to correlate this trait with temperament and performance traits as well as be a potential indicator of feed efficiency in confined cattle.