Researchers in this study found that giving taurine supplements for several months to Portuguese Water Dog puppies affected with infantile dilated cardiomyopathy (DCM) improved their cardiac function and prevented early death. Taurine is an amino acid essential for contraction of the heart muscle. The cause of infantile DCM appears to be a metabolic disorder that leads to low blood levels of taurine. Occurring shortly after weaning, infantile DCM is different from the DCM affecting other breeds. This project established that infantile DCM in Portuguese Water Dogs in inherited as an autosomal recessive trait. The research provides an important basis for further study that can lead to the development of a molecular test that would allow Portuguese Water Dog breeders to identify carriers and eliminate the disease entirely.