How did the animals prevail during the Battle of Cowshed?

In October, accompanied by several other farmers, Mr. Jones tries to recapture Animal Farm. Snowball has already trained the animals for war, however, and they take their defensive positions. The smaller animals attack the men and then pretend to retreat into the yard in defeat. Once the men follow, the larger animals ambush them. Mr. Jones kills one sheep and wounds Snowball several times with his gun, but the animals manage to overpower the humans. Boxer is thought to have killed a stable-lad, which upsets the stalwart horse. But it turns out that the boy is only injured, and he flees with the other men.