You may add up to 5 groups per animal category (cattle). For the purpose of this tool, a group is defined as a group of animals managed within the same animal category but with different diets or different manure handling practices. For example: if you have select the Animal Category of Beef-Steer Stockers, and half of these animals manure is handled via aerobic lagoon where as the other half is managed with an anaerobic digestor, they would need to be registered as two separate groups.