A review on the effects of part-time grazing herbaceous pastures on feeding behaviour and intake of cattle, sheep and horses

• Published in: Livestock science 2022-09, Vol.263, p.104982, Article 104982
• Main Authors: Molle, Giovanni, Cannas, Antonello, Gregorini, Pablo
• Format: Article
• Language: English
• Subjects: energy expenditure; herbivores; meat; milk; time-restricted feeding
• ISSN: 1871-1413; 1878-0490
• DOI: 10.1016/j.livsci.2022.104982

•Part-time grazing (PTG) ruminants display compensatory ingestive behaviour•They achieve levels of performance as good as 24 h-grazing ruminants if AT is 6-8 h/d.•PTG can results in reduction of energy expenditure and selective behaviour but fibre digestibility could be constrained•Beneficial FA in milk is usually higher in PTG than stall-fed ruminants•Horses show lower intake rates scaled to metabolic weight than ruminants•Horses are less adapted to short access time to pasture Part-time grazing (PTG) is the grazing technique based on the time-restricted access to pasture of farmed herbivores, usually supplemented indoors. This review evaluates the effects of the duration of access to pasture on the functional responses of grazing time and herbage intake rate in cattle, sheep and horses and the implications of these responses on diet selection, diet digestibility, energy expenditure, animal welfare, the performance of ruminants and the quality of their products (milk and meat). Ruminants with restricted access time to pasture display compensatory behaviour through increased intake rate, achieving similar levels of intake and performance compared with 24 h-grazing ruminants, particularly if access time is in the range 6-8 h/d. This can depend on the reduction of locomotion energy expenditure, and, sometimes, on the selection of a better quality diet than that on offer. Nevertheless, due to lower ingestive fibre trituration, fibre digestibility could be reduced, particularly with access time