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.

There was very strong evidence of an association between case/ control status and having a PregSure-vaccinated dam. A case had 18 times the odds of being born to a dam that was PregSurevaccinated rather than unvaccinated compared with a control, if the dam was first lactation and the calf did not receive colostrum from other cows, adjusting for type of milk fed (amOR 17.8; ci. 2.4, 134.4; p = 0.005). For calves that received colostrum from , and a case with a third or more lactation dam that did not receive colostrum from other cows had 132 times the odds of having a PregSure-vaccinated dam rather than an unvaccinated dam (amOR 132.0; ci 9.9, 1764.7; p = ,0.001), adjusting for type of milk fed. For calves with unvaccinated dams, there was no evidence of a difference in the odds of a case being born to a dam in first, second or third or more lactation compared with a control, adjusting for source of colostrum and type of milk fed (second lactation amOR 0.5; ci 0.1, 1.6; p = 0.23, third or more lactation amOR 0.7; ci 0.2, 2.4; p = 0.60). However, if the dam was PregSure-vaccinated, a case had twice the odds of having a second lactation dam (amOR 2.2; ci 1.1, 4.3; p = 0.024) and 5 times the odds of having a third lactation dam (amOR 5.3; ci 2.9, 9.8; p = ,0.001) compared with a first lactation dam, adjusting for source of colostrum and type of milk fed.