supplements for a tb in winter

[stretl]

Hi I have a tb who I only got six weeks ago he drops weight really easily and already is not at optimum weight. I have given him a round Bale to eat adlib and he's started on sugar beet and alfa original with Apple and codlivine for joints he's 8 but not sure what would be best to give him he's not in best condition just sorting his feet his hair is quite course and wondered if you knew what would be best to feed him on and supplements so I can try and still put Weight on him without getting daft