Daisy, I think if the chicken was fine afterward and the clobbering wasn't done out of meanness, I would take a chance and send it in. The Highlights people, if they like your story, may write and ask you to revise that bit, if they feel that it's not in the right Highlights tone. I know a few people who have had that happen.
If it's more than that one incident and something about the entire story seems a mismatch for Highlights, they'll just tell you so. I'm sure it's a great story, chicken-beating and all, and hope you find a home for it soon!