Clinical Diagnostics for Respiratory Disease in Farm Animals

Selection of animals for sampling should consider relevance to the problem at hand. The animals selected should have the following characteristics: 1). Relationship to contemporary problems, 2) Be in the initial phases of disease; and 3) Should have not received treatment for this disease. Sampling of animals should focus on those showing the same signs as affected animals, albeit earlier on in the process. Sampling animals after treatment or after death will have less value due to impact of antimicrobial or other therapeutics on the disease process. Animals in the “at risk” or affected groups which have chronic problems will either be of limited value or lead to findings that complicate interpretation of the problem. Animal information should include 1) Age of animals in the group and age of those selected for sampling; 2) number of days in the group (or days on feed); 3) environmental concerns (housing, bedding, cleaning, animal movement), 4) Group morbidity and mortality and how these correlate to prior groups, 5) Duration of problem in group and time since diagnosis (duration of disease) in sampled animals; 6) Clinical signs, treatment(s) and the animal responses, vaccination(s), ancillary treatments, and clinical diagnoses (working diagnoses) for the group.