Population growth and improving living standards are leading to a growing demand for beef. The understorey in the 19 million hectares of oil palm plantation worldwide represent a source of cattle feed, while also sparing additional land conversion for grazing. Research on cattle grazing under oil palm is novel and knowledge is lacking on long-term profitability and sustainability of the system, a major deterrent to cattle–oil palm farming system adoption. Here we review the current literature on cattle grazing in oil palm plantations, to highlight the knowns and unknowns of grazing impacts on the understorey, cattle and oil palm productivity, as well as economic implications. This review’s major outcomes are the following: (i) although understorey utilization as feed is a major advantage of cattle–oil palm integrated farming systems, declining understorey productivity under ageing plantation indicates the need for alternative solutions for sustained cattle productivity over the plantation’s lifecycle; (ii) oil palm yields were reported to increase under cattle integration but evidence was weak, both oil palm yields and the pathways through which oil palm yields are impacted by cattle grazing should be further explored; (iii) economic analyses showed cattle grazing under oil palm plantations was profitable for large-scale oil palm producers due to cattle sales, and returns were further enhanced by reductions in weeding and fertilizer costs; (iv) sustainable cattle grazing was found to be difficult in smallholder oil palm plantations due to land constraints and the current practice of free-grazing; options for improving grazing sustainability and profitability in these systems should be explored. This systematic review concluded that cattle integration in oil palm plantations has great potential but further research is required to develop locally specific productive and sustainable systems of grazed cattle integration with oil palm plantations.

人口增长和生活水平提高导致对牛肉的需求不断增长。全球 1900 万公顷油棕种植园的林下层是牛饲料的来源，同时也节省了额外的土地转换用于放牧。关于在油棕下放牧的牛的研究是新颖的，并且缺乏关于该系统的长期盈利能力和可持续性的知识，这是对牛-油棕养殖系统采用的主要威慑。在这里，我们回顾了当前关于油棕种植园牛放牧的文献，以突出放牧对下层、牛和油棕生产力的影响以及经济影响的已知和未知因素。本次审查的主要成果如下：（i）虽然作为饲料的林下利用是牛-油棕综合耕作系统的主要优势，老化种植园下林下生产力下降表明需要替代解决方案以在种植园的生命周期内保持牛的生产力；(ii) 据报道，在养牛一体化的情况下油棕产量增加，但证据薄弱，油棕产量和油棕产量受牛放牧影响的途径都应进一步探索；(iii) 经济分析表明，由于牛的销售，在油棕种植园放牧牛对大型油棕生产者来说是有利可图的，而除草和化肥成本的降低进一步提高了回报；(iv) 由于土地限制和目前的自由放牧做法，小农油棕种植园难以实现可持续放牧；应该探索在这些系统中提高放牧可持续性和盈利能力的选择。该系统评价得出结论，油棕种植园中的牛整合具有巨大潜力，但需要进一步研究以开发当地特定的生产性和可持续的放牧牛与油棕种植园整合系统。