Calf-Level Factors Associated with Bovine Neonatal Pancytopenia – A Multi-Country Case-Control Study

Jones, Bryony A.; Sauter-Louis, Carola; Henning, Joerg; Stoll, Alexander; Nielen, Mirjam; Van Schaik, Gerdien; Smolenaars, Anja; Schouten, Matthijs; den Uijl, Ingrid; Fourichon, Christine; Guatteo, Raphael; Madouasse, Aurélien; Nusinovici, Simon; Deprez, Piet; De Vliegher, Sarne; Laureyns, Jozef; Booth, Richard; Cardwell, Jackie M.; Pfeiffer, Dirk U.

Dam and sire characteristics ( Table 3, Table S4 ). There was no evidence of an association between case/control status and dam breed, dam was born on farm, dam was reared at another farm, or source of bull. Case dams (dams of cases) had increased odds of being in second or more lactation rather than first lactation compared with control dams (dams of controls). Case dams had 12 times the odds of previously giving birth to a BNP calf compared to control dams (mOR 12.02; ci 5.44, 26.57; p = ,0.001) Since previously giving birth to a BNP calf was considered to be on the causal pathway between other exposures and the outcome, it was not included in the multivariable model. Lactation number was correlated with many of the vaccination variables and was a potential confounder of the association between dam vaccination and case/control status. Cases had increased odds of having a Fleckvieh rather than a Holstein-Friesian or Red Holstein-Friesian sire, compared with controls. It was not possible to obtain estimates for all breeds because of low numbers of observations.