Interferons are cytokines, a type of signaling proteins involved in immune response that are released by affected cells in situations such as the invasion of viruses, bacteria, or parasites. Currently, human recombinant interferons are used in veterinary medicine to treat various conditions in animals; however, interferons are species specific and human interferon based drugs require higher dosages administered to animals to achieve remission. The purpose of this study is to determine how well species specific interferon medication works in improving health of domestic animals suffering from various conditions. Pharmaceutical substances based on recombinant bovine, swine, canine, equine interferons with or without an antibiotic will be administered to animals suffering from low immune response levels, viral and bacterial infections, stress, etc. In order to collect data for analysis veterinarians will examine the condition of animals subjected to study followed by completion of a questionnaire by animal owners. The use of species specific interferons will be analyzed to test the prediction that these pharmaceutical substances are more beneficial when compared to human interferon that are currently administered.