Depends what you are feeding and why, whether the horse is a good doer or not and the amount of acreage and access to grass in spring. If my horses were doing so little work they wouldn’t be getting anything at all other than a balancer for vitamins and minerals.
More info is required such as his condition, what are your plans for when the grass comes through and the days are longer will he be turned out more? what feed is he getting at the moment? it is normal to cut back on hard feed as they get more grass but sometimes the workload increases dramatically and they may actually need more.
assuming he's not skinny or v young (or anything else that would make him need calories) then I would scrap the Alfa and sugar beet and keep a check on haylage quantities / consider some hay instead
Obesity in horses is an epidemic and very dangerous.