Students use dichotomous keys to contrast the adaptations and identify the different breeds of pig. Practical fieldwork begins with the weighing of Gretel the ginger woolly Mangalitza, our free-range, pedigree, Austrian mountain pig. Students are then challenged to calculate Gretel's growth rate from the growth curve graph they have plotted, and compare the Mangalitza with results for our other rare breeds and a commercial hybrid pig. Practical activity continues with weighing and calculating the calories in Gretel's daily meal. Finally, using the formula N=I-(F+R), students calculate efficiency of energy conversion by each breed, and the map the MJ/day lost as metabolic heat. To conclude, students can pinpoint key methods in modern animal husbandry that are responsible for achieving highest productivity.