I have been researching and have information overload. What is the best medication to use to worm chickens & is the most effective? I read there is one that hits all types of worms & is the most effective but can't remember the name. It had a broad spectrum coverage & was easy to use. Reason why I'm asking is that I have noticed blood (fresh & bright) on the shavings below the roost in the morning twice this week. Advice would be greatly appreciated.