Opinion paper: is there a role for breeding for welfare improvement?

Increasing global demand for animal products produced with ever greater efficiency makes it unlikely that the pressure placed on livestock industries and therefore the animals themselves will diminish in the foreseeable future. Increasing affluence and awareness of welfare issues by society may drive improvements in welfare standards, but this may be regional rather than global in impact. Some complex welfare problems in intensive production systems, such as tail biting in pigs and feather pecking in hens, have existed for decades, have significant negative impacts on economic and environmental sustainability but have known solutions that are too costly for many producers to implement. Other welfare challenges, such as poor health control or high neonatal mortality in extensively managed systems, persist because management options for their mitigation are limited. Still other welfare challenges have been exacerbated in the past by imbalanced selective breeding on a narrow range of economically important traits, most notably in the dairy and broiler industries. Considerable variation exists between animals in their expression of negative welfare outcomes (e.g. in aggressive behaviour in pigs; Figure 1). Selective breeding leads to permanent and cumulative change, and breeding for appropriately targeted traits has the potential to benefit welfare without negative economic impacts or the requirement for major management change. This article will focus on three examples of welfare problems that have persisted for many decades and are tolerated as routine within current production systems, but which have the potential for improvement via selection. These examples are diverse and present ethical dilemmas, each to a different extent, with regard to the acceptability of using selection to improve welfare. The first example (improving lamb survival) is the least controversial of the three examples. The second (improving sheep resistance to foot infections known as ‘footrot’) is likely to benefit welfare but major improvements ought to be achievable on some farms without recourse to breeding through better prophylactic and therapeutic health management. The final example (reducing pig aggression) deliberately seeks to reduce expression of behaviours that are an integral part of the repertoire shown by all pig breeds and wild boar since housing systems that minimise this problem are not economically feasible.