In 1980, Schering-Plough Animal Health introduced Intra-Trac vaccines for kennel cough in dogs. For years, Iowa State University veterinary medicine researchers searched for cures for swine respiratory diseases caused by Bordetella bronchiseptica. Their conclusions spawned not one but two immunizations critical to animal health. Important vaccines to help control both kennel cough in dogs and atrophic rhinitis in swine were developed for the commercial market. Schering-Plough introduced AR-Pac vaccines for swine in 1977.