Bot-fly eggs can often be found on a horse’s lower part of its leg in summer. The eggs look like little yellow specks. If you find bot-fly eggs on you horse, ask an adult to scrape them off with a knife (be careful to not hurt your horse!). If your horse licks the eggs and swallows them, the eggs will develop into larvae inside its stomach or even its mouth, if they remain unswallowed. If you deworm your horse with ivermectin in early winter, it will destroy all the bot-fly larvae inside its body.