Morbidity from nonrespiratory diseases and mortality in dairy heifers during the first three months of life

Abstract

Objective To describe causes of death, mortality, and morbidity from nonrespiratory diseases in dairy calves. Design Prospective observational cohort study. Animals Convenience sample of 410 dairy heifers born between January and December 1990 in 18 southwestern New York herds. Procedure Heifers were examined weekly by a veterinary clinician during the first 3 months of life and all disease conditions were recorded. Results Crude risks for diarrhea, umbilical infection, and umbilical hernia were 28.8, 14.2, and 15.1%, and the median ages at first diagnoses were 2, 1, and 3 weeks, respectively. Mean durations of umbilical infection and umbilical hernia were 3.7 and 6.7 weeks, respectively. Crude mortality was 5.6%. Case-fatality risks were 12.8% for diarrhea during the first week of life, 5.1% for diarrhea after the first week of life, and 0% for umbilical infection and umbilical hernia. Diarrhea was diagnosed by the caretaker or the clinician; umbilical conditions were diagnosed by the clinician. The primary cause of death was diarrhea in 43%, pneumonia in 24%, septicemia in 10%, and other single causes in the rest of the 21 necropsied calves. Clinical Implications The high incidence and somewhat long duration of umbilical infection, the finding that diarrhea was the primary cause of death, and the high case-fatality risk for diarrhea during the first week of life suggested that calf caretakers need training in the prevention and treatment of these conditions. (J Am Vet Med Assoc 1996:208:2043-2046)