"He had really serious injuries as a result of that," Deacon said.
"When we arrived there were family and friends there and he was just unconscious on the ground."
The man was sedated at the scene and Deacon's crew performed a rapid sequence intubation (RSI) to assist his breathing.
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Deacon said animal injuries as a result of human interaction is not uncommon.
"They are often not deliberate, I'd say the horse was properly unfamiliar with him.
"Horses in the area aren't ridden a lot, they are fairly free roaming and don't have much human contact as horses in other areas," Deacon said.
The paramedic said the horse was not in sight when he got there.
"Family seemed very calm when we got there."