Some abstracts do not have video files because ASAS was denied recording rights.
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History of management procedures and hierarchy in dairy cows
Objectives – this study assessed social interactions between cows in a 186 lactating cow herd, split into high milk yield (<35 weeks into milking) and a low milk yield (>35 weeks into milking) groups. The shifting hierarchical behaviours of the cows over 20 days was observed through analysis of video. The objective was to determine whether cows with a higher history of management procedures associated with treatment for common conditions, mastitis, lameness and dystokia, would be lower in rank in the social hierarchy, and show more fluctuation in rank, than cows with a low management procedure history.
Methodology – a still image photo-library of the cows in the herd was compiled, so that every cow could be identified from video recordings. Cows were identified as being in a high management history group (HMG) or a low management history group (LMG) based on their electronic farm management record. For blind analysis, the categorisation into low and high management groups was made after the video analysis had been completed.
Cows were filmed at the feed barrier using 1080p 50fps GoProHero 4 cameras, each camera supported to give a stable image along the feed barrier. Activity and time budget analysis of individual cow interactions from the video images allowed dominant (+) and submissive (-) interactions between cows to be noted.
Results and Interpretation - no significant difference was found in the ‘average hierarchical rank’ between cows in the HMG and the LMG (p=0.330). Heifers did rank significantly lower than cows, for example – when comparing heifers to cows in their 3rd lactation (p=0.004). The LMG showed a higher variability (deviation in means score) in rank than the HMG.
Innovation – this pilot study may aid understanding of possible long term effects of common dairy management procedures. With further development, this method could a) inform steps to reduce long term impacts of common procedures b) utilise altered hierarchical behaviour as a detection tool for cattle showing long term deleterious effects of previous management procedures.
Conclusion - cows that had a higher history of management for common dairy cow conditions – lameness, mastitis, dystokia – did not experience long term effects on hierarchical behaviours during feeding. However, significant behavioural differences in groups based on age were detected.
Keywords: dairy cows, management, disease, hierarchical, behaviour