Date of Award


Degree Type


Degree Name

Master of Science (MS)


Food Studies


Rick Welsh


Cattle;Dairy;Kelp;Methane emissions;Seaweed;Tacit knowledge

Subject Categories

Agriculture | Life Sciences


While demand for dairy products increases globally, dairy cattle and other ruminants emit over a quarter of total methane emissions through enteric fermentation (Carrazco et al., 2020). A potent greenhouse, methane has eighty times the global warming potential of carbon dioxide over a 20-year period (Black et. al., 2021). Consumer demand for more environmentally friendly dairy products paired with state climate goals has the dairy industry seeking ways to reduce methane emissions. One proposed solution is to feed algae (e.g., seaweed, kelp) to cows, as some live animal trials have shown it can reduce methane emissions by 80% (Stefenoni et al., 2021). Many dairy farmers already feed algae to promote cow health (Antaya et al. 2019). In this thesis I discuss the use of algae as a feed supplement, drawing on interview and survey data collected from conventional and organic dairy farmers, dairy cattle nutritionists, and animal science researchers. I explore their beliefs about algae supplements through a theoretical framework of productivist and constructivist knowledge paradigms- namely tacit and codified knowledge. I investigate what farmers, nutritionists, and researchers know about algae-feed supplements, why they feed or recommend them, and what sources of information they rely on for trusted information about feed supplements. I find that dairy farmers feed algae for herd health reasons and for those who do not, they would need incentives to feed algae for methane reduction. Farmers primarily trust their nutritionist with feed decisions. Nutritionists and researchers obtain information pertaining to feed supplements from animal science journals, and trust data from reputable scientific experiments. This mixed methods study is part of a nationwide multidisciplinary research project investigating the feasibility of using algae feed supplements to reduce methane emissions and improve dairy productivity.


Open Access

Included in

Agriculture Commons



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