Effects of tree arrangements of silvopasture system on behaviour and performance of cattle: a systematic review

Abstract

This review aimed to provide a critical and systematic evaluation of the scientific literature about the effect of tree arrangements of the silvopasture system on the thermal environment, behaviour, and performance of cattle. We conducted a search using Web of Science and Google Scholar to identify the key literature of the theme. Peer-reviewed published articles written in English, comparing one or more tree arrangements of SPS to treeless pasture or comparing shaded and sunny areas within the SPS, were selected. The resulting manuscripts (n=191) underwent a four-step PRISMA appraisal process. This process resulted in a final sample of 37 articles, which were used for recording metadata, bibliometric analysis, and assessment of the results, using the software R. Of the 37 articles, 20 studies evaluated dairy cattle (behaviour: 14; performance: 7) and 17 evaluated beef cattle (behaviour: 6; performance: 12). The main behaviours evaluated were grazing (95%) and ruminating (90%), while weight gain (89%) was the main performance variable evaluated. The co-occurrence network analysis highlighted that the studies related the animals' response to improving the thermal environment promoted by silvopasture systems. The main difference among tree arrangements evaluated by the studies was tree density, which ranged from 5 to 800 trees/ha; most studies covered SPS with row of trees (single row, n=16 and multiple rows, n=19). Most studies (n=32) were carried out in Brazil. The evidence of this review showed that regardless of tree arrangement, the silvopasture system improves the thermal environment for cattle, although some effects on behaviour and performance are inconclusive.