Haddad, J. P., Dohoo, I. R., VanLeeuwen, J. A., Tiwari, A., & Keefe, G. P. (2004). Seropositivity for agents causing neosporosis, bovine viral diarrhea, enzootic bovine leukemia, and Johne's Disease and their relationships with increased calving to conception interval in Canadian dairy cows. In WBC (p. 74). Quebec City, QC, Canada.