I have recently purchased a gray six year old gelding from a rescue and I have noticed he is always sweating on its neck/shoulder on the left side. The rescue said they got him from a kill truck in February and he was starved and it looked like he had been abused. It has been an average temperature of 40 degrees farenheit so I dont think it's the weather. He dosent seem like it is bothering him. He is very happy and content but I would like to make sure there aren't any major underlying problems.