Short project description

Dairy cows considerably contribute to greenhouse gas (GHG) emissions by eructating methane, a natural product of microbial fermentation in the rumen as well as a powerful GHG. Among the available tools to reduce enteric methane emission by targeting rumen metabolism and inhibiting methane producing microorganisms, the feed additive Bovaer® (3-Nitrooxypropanol; 3-NOP) is considered the most promising, and large scale implementation in Danish commercial dairy farms is planned (https://fm.dk/nyheder/nyhedsarkiv/2024/april/bredt-flertal-i-folketinget-fordeler-ca-5-mia-kroner-fra-det-groenne-raaderum/).

While Bovaer® effectively lowers enteric methane emissions by targeting key microbial enzymes, its potential side effects on cow welfare remain unclear. Notably, Danish studies reported that Bovaer® supplementation reduced feed intake, which is often seen when experiencing discomfort. Since discomfort in cows often manifests in reduced activity, grooming, and social behaviour, among others, this study aims to investigate the behavioural response of lactating cows to Bovaer® supplementation.

As part of a large experiment investigating the effects of several doses of Bovaer® on behaviour, performance, and emissions of Danish Holstein lactating cows conducted in the departmental resident Danish Holstein herd of Aarhus University (Tjele, Denmark), this thesis project will examine the undisturbed behaviour of dairy cows feed-supplemented with one of three doses of Bovaer® (0, 60, 90 mg/kg DM). The student will conduct a literature review, label behaviour from video recordings, and analyse original data. The student will be based in AU Viborg and be part of a research team.