This paper illustrates how a practical problem can shape the production of theoretical knowledge through a case study of bloat in the New Zealand dairy industry. Bloat became troublesome in New Zealand from the late 1930s as a consequence of pasture improvements designed to increase agricultural productivity. Clover and other legume species with high nutritional content, which became widespread within NZ pastures, produced higher animal growth rates and increased butterfat levels in milk, but also had serious adverse effects. The rich food produced so much foam and gas within the rumen that the cow’s belly swelled causing, among other problems, fatal pressure on lungs and heart. Bloat afflicted the herds of so many New Zealand farmers and had such major economic consequences that the dairy farming community asked that government scientists investigate and find a remedy for the malady.

Solving the problem of bloat required sophisticated multi-disciplinary approaches. It required studies of ruminant metabolism, the chemistry and nutrition of grasses and clover (including seasonal changes), and the bacteria in the ruminant stomach. Theory was not simply available to be ‘applied’ but new areas of study, such as ruminant metabolism, had to be developed. Moreover, any proposed solution had to be economically viable and feasible in the paddocks of a normal working dairy farm under New Zealand pastoral conditions. The research programme that resulted combined field and lab scientists from different disciplines (biochemistry, microbiology, chemistry, physiology) who worked together to produce new knowledge. Researchers developed innovative methods to investigate the metabolic processes in vivo. In so far as separation is possible, the paper will focus on biochemistry in illustrating the ways in which new knowledge and approaches came from researching the agricultural problem.