In intensively operated dog breeding kennels bacterial infections are very significant in perinatal mortality. 2. Staph. aureus, Streptococci (type G) and also beta-haemolytic E. coli were transmitted intra-uterine or by the infected genital tract to the puppies. In many cases they are the cause of septicaemic death of the puppies. 3. A second important cause of infection is subclinical mastitis of the bitch, leading to septicaemic death of newborn puppies. 4. Prophylactic hygienic measures make possible a prognosis concerning the risk of perinatal death. This includes examinations of the dog and the bitch ante coitum, bacteriological examination of the genital tract of the bitch, and a bacteriological examination of the milk before the date of birth. 5. Prophylactic hygienic measures in combination with antibiotic treatment of the bitch or the puppies could reduce the losses of puppies to less than 10%.
