There is growing consumer interest in food production and in recent years the dairy industry has been subject to increasing public scrutiny. Consumers frequently highlight the welfare of dairy cows as an issue of concern (Wolf et al, 2016; Jackson et al, 2022) and management practices and conditions that adversely affect animal welfare may negatively influence public perception of the industry and undermine consumer trust. Lameness is well-recognised as a condition associated with reduced welfare but remains common on dairy farms, with a prevalence of over 20%, a figure unchanged since the 1980s (Afonso et al, 2020; Thomsen et al, 2023). Although pain is the most obvious welfare compromise associated with lameness, it is recognised that there are wider negative welfare effects; using the Five Domains Model as a framework (Figure 1) (Mellor et al., 2020), these are discussed here.
Domain one: nutrition
Do lame cows go thin or do thin cows go lame? Low body condition score predisposes cows to lameness (Lim et al, 2015; Randall et al, 2015), but it has also been demonstrated that lame cows exhibit changes in feeding behaviour such as reduced time spent feeding, fewer, shorter feeding bouts, and reduced feed consumption compared to non-lame cows (Miguel-Pacheco et al, 2014; Norring et al, 2014; Thorup et al, 2016; Grimm et al, 2019; Frondelius et al, 2022). Additionally, grazing lame cows have been found to take fewer bites per minute than grazing non-lame cows (Walker et al, 2008) and lame cows are less able to compete at the feed face, possibly causing them to consume less nutritious feed left over after other cows have fed.
Changes in feeding behaviours associated with lameness may result in malnutrition and a poor nutritional state that compromises welfare. Poor nutrition may also lead to feelings of malaise, and it is possible that lame cows may experience hunger, which can negatively affect their mental state (domain five).
Domain two: physical environment
Whilst environmental factors such as overstocking are known risk factors for lameness (King et al, 2016), changes in the environment occurring as a result of lameness may contribute to reduced welfare. For example, although separating lame cows from the herd is good practice, complete isolation of lame cows in a treatment pen can be stressful (Herskin et al, 2007) – an effect that may be mitigated by separating cows with a herd-mate for company (Whay and Shearer, 2017). Additionally, if management of the treatment pen is suboptimal, lame cows might be exposed to environmental conditions such as dirty bedding and air pollutants. However, these welfare impacts are not exclusive to lame cows and can be readily ameliorated by improving the management of treatment pens.
Domain three: health
Lameness is painful, impairs mobility, and is associated with poor health – all negative welfare effects. Furthermore, alterations in nutrition associated with lameness may contribute to health disorders such as metabolic disease (Calderon and Cook, 2011), further negatively impacting welfare. Pain, weakness and exhaustion related to lameness all contribute to poor mental state and compromise welfare domain five. Furthermore, lame cows can develop hyperalgesia (Whay et al, 2005) that may compromise welfare in the longer term, even after the lameness event has passed.
Domain four: behavioural interactions
In a positive welfare state, an animal has opportunities to make choices and have some control over its interactions with the environment, other animals, and people (Mellor et al, 2020). Lameness has the potential to reduce a cow's ability to engage in certain behaviours and limit available choices, reducing agency and compromising this aspect of welfare.
Interactions with the environment
The effects of lameness on lying and standing behaviours are widely studied in cows. Lameness is associated with fewer, longer lying bouts and a higher overall proportion of the time budget spent lying (Tucker et al, 2021; Magrin et al, 2023). Whilst lying is an important behaviour for all cows, lameness may lead to cows prioritising lying over behaviours that may be more appropriate for the current environment, interfering with healthy behavioural-environment interactions and contributing to good welfare. For example, as the temperature humidity index increases lying time of healthy cows is reduced (Nordlund et al, 2019) and standing time is increased (Allen et al, 2015) – likely a behavioural adaptation to aid cooling. However, lame cows may be reluctant to stand, potentially reducing the effectiveness of cooling and increasing the likelihood of heat stress. Other changes in behavioural-environment interactions of lame cows (compared to non-lame cows) that may be associated with poorer welfare include a higher proportion of cows lying outside of the cubicles (Galindo and Broom, 2002), alterations in brush use (Mandel et al, 2018; Weigele et al, 2018; Burton and Blackie, 2024) and differences in how cows use available space (Frondelius et al, 2022).
Interactions with other cows
Lame cows exhibit altered behavioural interactions with healthy cows such as an avoidance of antagonistic behaviours and being more frequent recipients of social licking (Galindo and Broom, 2002). It is unclear whether these changes in social behaviour have negative welfare impacts as avoiding antagonistic interactions may lead to reduced risk of injury and reduced social stress, and social licking is associated with comfort and bonding in cattle (Laister et al, 2011; Pinheiro Machado et al, 2020) – factors that might be expected to be associated with a more positive welfare state. However, the affective response of individual cows to changes in their social behaviour is unknown, and changes in a cow's behavioural repertoire may negatively affect their emotional state.
Interactions with people
Negative interactions with people lead to heightened fear and anxiety in cows (Rushen et al, 1999) and some handling methods (such as hitting) may cause pain. There is a paucity of data indicating how lameness affects human-cow interactions, but it has been suggested that lame cows may be subject to negative handling experiences as people get frustrated with the cow's reluctance to move (Whay and Shearer, 2017), a plausible hypothesis. It is also possible that ineffective detection of lame cows (Babatunde et al, 2019), may mean cow handlers might not recognise a lame cow and make suitable handling accommodations (for example, allowing extra time for movement), potentially further contributing to lame cows' aversive experiences.
Conclusion
Lameness is a common condition of dairy cows that is associated with reduced welfare. Although pain is arguably the most obvious welfare compromise associated with lameness, by using the Five Domains Model (Figure 2), we can see that lameness has wider negative welfare impacts that also merit consideration.
