Sustainable stockbreeding requires livestock with a steady body size

An archaeological research project is analysing livestock’s size from the Late Bronze Age to Late Antiquity (8th c. BC - 9th c. AD) through the comparative analysis of three geographical areas in South-Western Europe. The study provides ideas for a more sustainable stockbreeding today.

Silvia Valenzuela (Institución Milá y Fontanals, IMF-CSIC) directs the project, which focuses on livestock husbandry (cattle, sheep, goats, and pigs) in areas of the centre and north of Italy, the North-East and the South-West of the Iberian Peninsula (present-day regions of Catalonia and Extremadura, and southern Portugal). These areas were chosen because of their close location and because they experienced similar historical processes.

Ariadna Nieto (left) and Silvia Valenzuela (right) in the Institución Milà i FontanalsThe ERC research project involves innovative techniques such as the study of ancient DNA, the study of isotopes to track mobility (strontium and oxygen) and the analysis of the changes in livestock husbandry’s composition through history. The project also sheds light on aspects that had not been researched in depth previously -- until now; knowledge about size changes in livestock through time in the area was limited.

“We can extract a lot of information from archaeological bones and teeth. From a tooth we can know the age, analyse the DNA, and investigate the mobility pattern and the biometrics”, explains Ariadna Nieto, one of the postdoctoral researchers of the project in an interview.

More than 2.000 years ago, livestock in these areas was fed according to free-range husbandry practices. These extensive spaces are opposed to our current intensive herding system, which favours high productivity and reduces the biodiversity of the planet. Consequently, our livestock today is bigger and heavier than the animals in the Iron Age, the last period of Prehistory.

When asked about the relevance of studying livestock’s size differences through history, Valenzuela clarifies that body size matters because it is related to the amount of meat that can be obtained. “The larger the animal, the higher the productivity per animal”, she asserts.

In Catalonia we are producing more fodder for stockbreeding than cereal for human consumption

The downside of this is that bigger animals require more water and food than smaller ones. The consequences of the intensive breeding system are noticeable in the production, the biodiversity and the dependence of long-distance commerce. In order to supply the demand of food for livestock husbandry, Europe imports 80 millions of tonnes of fodder per year from all over the world. “In Catalonia we are producing more fodder for stockbreeding than cereal for human consumption”, Nieto adds.

In this sense, our current husbandry practices are similar to the systems used during the Roman period, after the Iron Age (from the 3rd. century BC to the 5th c. AD), when shepherding intensified in order to obtain a higher productivity. Valenzuela adds that both periods involve “large and interconnected systems and economies” in which animal body size progressively increased.

“In these systems we depend on long-distance trade, and if that fails, everything does”, she asserts. The archaeologist explains that these production levels necessarily have to rely on transnational commerce, which results in plenty of socioeconomic implications.

The project can help to find methods for a more sustainable livestock husbandry, as it reveals that extensive breeding – although less productive – is more sustainable over time.

In the next months the researchers will focus on the area of the South-Western Iberian Peninsula, the area less explored so far. Interestingly, the first results suggest that this region had steadier livestock production throughout time.

Read the academic paper:

Valenzuela-Lamas, S., & Albarella, U. (2017). Animal husbandry across the Western Roman Empire: changes and continuities. European Journal of Archaeology, 20(3), 402-415.

Nieto-Espinet, A. Trentacoste, A., Valenzuela-Lamas, S., (in press) Continuïtats i canvis en la ramaderia a Catalunya del primer mil·leni aC a la tardoantiguitat. Adaptació ecològica o canvis socio-polítics?, Tribuna d'Arqueologia.

Paula Talero Álvarez and Sabela Rey Cao / Delegación del CSIC en Catalunya