How effective is physical enrichment for dairy calves? A systematic review

Abstract

Abstract Physical enrichments have been widely used in the dairy cattle systems. Providing more space, outdoor access, objects, and changes in flooring materials can enhance the welfare of dairy calves, by encouraging natural behaviours. However, how effective is physical enrichment for dairy calves? We conducted a systematic review regarding the effects of physical enrichment on the behaviour, feed intake, growth, health, and physiology of dairy calves. A search was conducted using the Web of Science and PubMed databases to identify and assess peer-reviewed studies published in English before April 2024. The resulting articles ( n = 1,033) underwent a PRISMA 4-step appraisal process, resulting in a final sample of 64 studies. Increasing space allowance in calf-rearing environments (assessed in 18 studies) was associated with higher levels of calves’ activity, including increased grooming and play behaviours, as well as lower cortisol levels. However, there was no clear evidence that increased space allowance affects growth, while feed intake and health appeared to be unaffected. Studies ( n = 17) that investigated the effects of enclosure types (indoor vs outdoor housing) found associations between outdoor housing and improved health parameters, while outcomes related to growth and feed intake were inconsistent. The flooring types evaluated in studies ( n = 20) were categorized into harder surfaces, such as concrete or wooden slats, and softer materials such as straw, rubber mats, or sawdust. Flooring type appeared to influence calf behaviour and feed intake, while the impact on calves’ growth, health, and physiology varied depending on the flooring types being compared. Overall, softer and organic materials provided more comfort for calves and provided a cleaner environment, whereas calves generally avoided harder surfaces for lying down. The use of objects for enrichment (assessed in 19 studies) influenced calf behaviour. However, there was no effect on growth, feed intake, health, or physiology reported across these studies. Overall, our findings indicate that physical enrichment increases calf activity. In contrast, the effects on growth feed intake, health, and physiology are inconsistent or affected only by certain types of enrichment.

The authors' abstract, as published at the source. Annals of Animal Science, 2026 · DOI ↗