Determining respiratory or circulatory health condition in animals for improved management

A method and system for managing at least one animal is disclosed. The method can include imaging, such as ultrasound imaging, a lung of a live animal, such as a ruminant or bovine. The imaging can be performed to determine a degree of respiratory damage from past respiratory illness. After imaging, information regarding respiratory damage can be used to select at least one aspect of the treatment, care or disposition of the animal. For example, the information can be used to select the amount or type of feed provided to the animal at a feedlot. The information also can be used to select how long the animal should be housed at the feedlot prior to slaughter. If an animal is diagnosed with a respiratory illness, information about its degree of respiratory damage from past respiratory illness also can be used to select the appropriate medical treatment or lack of treatment.