During a six month field study in a cattle practice un Upper Bavaria, Germany, the incidence of neonatal diarrhea was determined in 519 calves on 36 farms. The objective was to discover the factors affecting the incidence of neonatal diarrhea in calves, in particular the housing during the first two weeks of age. The evaluation was performed by the clinical examiation of the animals (at least every 48 hours) and on the basis of a questionnaire the researchers completed with the farmers. For some questions depending on the personnel of the farms the three veterinarian researchers evaluated the situation on farm by experience. From each calf, a fecal sample was taken on the eighth day of life and in case of scours on the first day of illness from the rectum. Enteropathogens (Rotavirus, Coronavirus, ETEC and Cryptosporidium) were detected by BIO-X lateral immunochromatography test. For the detection of Giardia oocysts, fecal samples taken during the fourth week of age were sent to a laboratory.