Best start to life – meeting behavioural and nutritional needs to promote welfare in farm animals

“...as more individuals are produced than can possibly survive, there must in every case be a struggle for existence... Those individuals who possess any advantage, however slight, over others, will have the best chance of surviving and of procreating their kind.” On the Origin of Species (1859), Charles Darwin.

Evolutionary pressure selects for traits that confer an advantage to ensure survival of the species. Some of these traits are manifested as different behavioural and biological needs that the animals have a strong motivation to fulfil. These traits have evolved over thousands of years and are relevant for the environment in which the animals have evolved. However, modern agricultural practices remove animals from their natural habitat and keeps them in a more confined and controlled environment. Even though there has been a strong genetic selection for animals that perform well in commercial environments, most of the original behavioural needs still remain in farm animals. This can lead to a large discrepancy between the environment in which their needs evolved and their present environment. 

For example, ruminants form a strong filial bond between mother and young, which increases the chances of survival by restricting maternal care and milk availability to their own offspring. Similarly, a strong motivation to suckle increases the probability of survival of the newborn. However, a strong mother-young bond becomes undesirable in commercial dairy systems. In dairy cattle, newborn calves are separated from their mother a few hours, and in some instances a few days, after birth. Separation at birth leads to ethical concerns and reduced public acceptance while separation after a few days leads to a stronger stress reaction to separation. Similarly, a strong motivation to suckle allows young calves to meet their nutritional needs to reach their full growth potential. However, in order to reduce labour and feed costs calf milk feeding (frequency and volume) is usually restricted in commercial dairy farms. Therefore, the calves’ behavioural and nutritional needs are not met which can lead to behavioural problems, restricted growth and reduced production potential as adults. 

Similar conflicts arise in egg production systems where modern laying hens have evolved from the jungle fowl that have a strong motivation to forage for food. In nature, jungle fowl need to spend up to 94% of their active time foraging (pecking and scratching) for food to meet their nutritional needs, as food can be hard to find in a complex environment. This strong motivation to forage is still very much present in modern domestic egg laying birds. However, in commercial situations, performing food searching behaviours for most of the day is no longer relevant since food is so easily and readily available that birds are able to consume up to 73% of their daily intake in as little as 90 min. The mismatch between their natural needs and the farm environment increases the risk of developing injurious feather pecking (which is consider a redirected foraging behaviour) and cannibalism. The most effective way of preventing feather pecking from developing are interventions during early rearing. 

In this lecture, I will present examples of my research which focuses on evaluating the welfare consequences of conflicts between behavioural and nutritional needs and modern production environments. I will also present alternative farming practices during rearing that allows animals to express and fulfil their natural needs to give them the best possible start to life to be able to thrive in a commercial environment.