Not 1.8 tonnes of trailer complete with horse, tack, water etc etc....I wouldn't. That's just not enough tow cap however you juggle it. I'd like to see that pull a horse trailer off road (flat wet grassy field, muddy track, etc) after all horse trailers are taken off Tarmac on a regular basis.
Anyhoo that is not a horse towing vehicle...proper hoss pullers are big, square, have a roof, the aerodynamics of a fridge, do 22mpg, have a tow bar, a whip in the boot, straw on the carpets and smell of horse ****.