This episode examines a 2026 study that explored whether pre-breeding behavior can predict which bulls will sire the most calves in multi-sire breeding pastures. Researchers fitted bulls with collars containing accelerometers and proximity sensors to objectively measure activity levels and social interactions before the breeding season. The goal was to determine whether behavioral traits such as activity, social connectedness, and interaction patterns were associated with a bull’s eventual siring capacity.
The study found that more active bulls tended to sire more calves, and bulls that were more socially connected within the group also appeared to have greater breeding success. Researchers used complex network-analysis measurements, including eigenvector centrality and relative strength, as indicators of social influence and interaction among bulls. Bulls with more diverse interactions across the bull group generally had higher siring capacity than bulls that spent most of their time with only a few herd mates.
The hosts found the concept particularly intriguing because previous efforts to predict breeding success often relied on subjective observations, while this study used objective monitoring technology. However, they also highlighted several limitations, including a relatively small sample size, missing sensor data, differences in bull grouping between years, and challenges associated with bulls entering or leaving breeding groups due to injury.
Another important finding was that some behavioral traits, especially activity level and social connectedness, showed moderate repeatability from year to year, suggesting they may reflect inherent characteristics of individual bulls rather than temporary conditions. The hosts emphasized that while the results are promising, the study should be viewed as an early step rather than definitive evidence. They concluded that larger studies across more herds and breeding environments will be necessary to determine whether wearable technology can reliably help producers identify the most effective breeding bulls before turnout.
Podcast (bovine-science-with-bci): Play in new window | Download