Housed dairy cows utilise varied environmental enrichments and show diverse inter-individual variation in habituation

There is currently a focus on the importance of providing positive experiences to farm animals, which can be facilitated through the provision of environmental enrichment. Brushes are an established enrichment resource for dairy cows, however, enrichment opportunities beyond this appear to be limited. Resources which animals habituate to rapidly may be economically unviable and provide limited welfare benefits. This study aimed to assess the utility of simple point source enrichment for housed dairy cows, to evaluate how cows habituate to enrichment over time and whether cows show a preference for different enrichments. A preliminary experiment provided two groups of dairy cows (n=71) with continuous access to a novel object in the home pen for three weeks. In a further experiment, two groups of cows (n=75) were provided with the same novel object alongside continuous access to an outdoor concrete yard for nine weeks. Interaction with enrichment was quantified using sampled continuous 24-hour periods of video footage. Most cows continued to use both resources throughout the study. After two months the proportion of cows that continued to use the object and the outdoor yard was 0.88 ± 0.01 and 0.96 ± 0.02 per day. Cows spent on average 2.72 ± 0.37minutes per day interacting with the novel object by the end of the trial, comparable to previously published data quantifying brush use in cows. We identified significant variability in the extent of habituation between cows. Although most cows declined their active utilisation of enrichment to some extent, one-quarter of cows alternatively increased the time they spent using enrichment by the end of the study. Linear models revealed a significant positive relationship between how much time individual cows used enrichment when initially provided and the extent to which they habituated to it by the end of the study (P<0.05), with the highest users of enrichment initially, showing the greatest decline in enrichment use over time. Cows spent more time outside at 72.76 ± 5.13minutes per day (P<0.05) than using a novel object after two months. These results indicate that housed dairy cows will utilise additional and novel forms of enrichment if provided, suggesting the availability of these resources to be beneficial. Cows’ habituation responses to enrichment appears to not be a consistent group-level response. The provision of greater opportunities for environmental enrichment should be considered for dairy cows alongside the evaluation of enrichment use at the individual level.