BOOST! Probiotic Mealworm Additive combines protein (from a 5 LB Mealworms or 5 LB Grubs Bag - Sold Separately) with gut-supporting microbes - a great combination for energy, feather growth, and digestion. Clinical studies show that daily use supports digestion and immunity. This powerful Probiotic will BOOST! the health of your chickens! We recommend combining the Probiotic with Zylina Healthy Mealworms 5 lb or Zylina Healthy Grubs 5 lb (sold separately). The Zylina Probiotic is administered in 2 simple steps: 1 - Pour the Entire Bottle of Probiotic in a 5 LB Bag of Mealworms or Grubs and 2 - Mix thoroughly and feed your flock. The Probiotic adheres to mealworms or grubs and chickens will devour the probiotic mealworm treat!