What is ‘natural’?

Published 3 April 14

View from Duncan Pullar

‘Unnatural’ is a term often used by campaign groups as an argument against modern livestock farming, as they try to specify the conditions under which they believe livestock should be kept. But is there any basis for the claim that some systems are ‘unnatural’?

First, it’s important to recognise the difference between ‘normal’ and ‘natural’. In a 1986 paper, Jenson described abnormal behaviour as an ‘untypical reaction to a particular combination of motivational factors and stimuli’. He says much abnormal behaviour can be regarded as stress-coping responses, such as stereotyped motor patterns, abnormal aggression and, in some species, cannibalism. By contrast, normal is when the animal can express the behaviour inherent in its genetic make-up, which would eliminate the expression of these signs.  

‘Natural’ is harder to define when talking about animals that have been domesticated for so long. Historical records show cows were probably first domesticated about 8,000 years ago in what is now Iran, and separately in the Indus valley. Humans soon started selectively breeding to make them easier to work with and more productive.

As domestication progressed, we have needed to adapt the way in which we look after our animals. The ‘contract’ between cow and cow-keeper has to be two-way to succeed. The cow supplies us with a product (milk) and we give it an environment where it can flourish and express the five freedoms  developed as the benchmark of animal welfare. The fact that the cow is extremely adaptive means we have changed her needs and we have, therefore, a responsibility to meet them.  So we are arguing about the workings of a manmade system – as all farming is – and not what is natural, as is found in the wild or in the ‘let nature take its course’ sense. 

The science answers some questions bur raises others. Charlton, G., Rutter, S. M., East, M., and Sinclair, L. A.(2010) showed that higher yielding dairy cows chose to be indoors for 91% of the time when offered a choice between a TMR ration and quality grazing  (but this was in animals with no access to pasture during the rearing period).  In general, the literature clearly shows that cow preference for pasture varies largely and is dependent on a large number of factors including prior experience and metabolic demands.  

As for grazing, is it natural or normal behaviour? The dental equipment of the cow is pretty well developed for a grazing behaviour but there is no evidence of cows exhibiting stress or abnormal behaviour if they are denied the ability to graze when all their other needs are met. We are carrying out further research at Harper Adams, through our Research Partnership, looking at what choices cows make when they can pick their environment.

Overall, a realistic and economically sound response for high-yielding cows in particular is to put them in a building where their needs and freedoms can be fully met. The important thing is that the design and management of that building is good enough to meet the freedoms – including the freedom to express normal (ie, behaviour free from stress signals rather than ‘natural’ behaviour) – and support a profitable production system.