<p>While it is clear that animal production poses environmental and ethical challenges for society, it is less clear which impact animals have on the productivity of single farms. A sample of 2500 Swiss farms was used for descriptive comparisons between farm types and between farms without animals, before land, labour and capital productivities were explained in a regression by animal density. Results show that animals contribute positively to land and labour productivity for farms that are not specialized in horticulture and permanent crops. However, animals’ contribution to capital productivity is generally low or even negative and do not seem to be an optimal investment. Farms without animals have a higher labour productivity, land productivity and capital productivity than farms with animals. A careful analysis of the results indicates that animals, as a production factor, contribute less to productivity than other production factors, but that this fact is overshadowed by the considerable gains of farm specialization. Therefore, the clearest result of our exercise was not the modest profitability of animals on the farms but the considerable economic benefits of specialization. </p>