title: Calf-level factors associated with bovine neonatal pancytopenia--a multi-country case-control study.
abstract: Bovine neonatal pancytopenia (BNP), a high fatality condition causing haemorrhages in calves aged less than 4 weeks, was first reported in 2007 in Germany and subsequently observed at low incidence in other European countries and New Zealand. A multi-country matched case-control study was conducted in 2011 to identify calf-level risk factors for BNP. 405 BNP cases were recruited from 330 farms in Belgium, France, Germany and the Netherlands by laboratory confirmation of farmer-reported cases. Up to four calves of similar age from the same farm were selected as controls (1154 calves). Risk factor data were collected by questionnaire. Multivariable modelling using conditional logistic regression indicated that PregSure®BVD (PregSure, Pfizer Animal Health) vaccination of the dam was strongly associated with BNP cases (adjusted matched Odds Ratio - amOR 17.8 first lactation dams; 95% confidence interval - ci 2.4, 134.4; p = 0.005), and second or more lactation PregSure-vaccinated dams were more likely to have a case than first lactation vaccinated dams (amOR 2.2 second lactation; ci 1.1, 4.3; p = 0.024; amOR 5.3 third or more lactation; ci 2.9, 9.8; p = <0.001). Feeding colostrum from other cows was strongly associated with BNP if the dam was not PregSure-vaccinated (amOR 30.5; ci 2.1, 440.5; p = 0.012), but the effect was less if the dam was PregSure-vaccinated (amOR 2.1; ci 1.1, 4.0; p = 0.024). Feeding exclusively dam's milk was a higher risk than other types of milk (amOR 3.4; ci 1.6, 7.5; p = 0.002). The population attributable fractions were 0.84 (ci 0.68, 0.92) for PregSure vaccination, 0.13 (ci 0.06, 0.19) for feeding other cows' colostrum, and 0.15 (ci 0.08, 0.22) for feeding dam's milk. No other calf-level factors were identified, suggesting that there are other important factors that are outside the scope of this study, such as genetics, which explain why BNP develops in some PregSure-colostrum-exposed calves but not in others.
authors: Department of Population & Production Health, Royal Veterinary College, North Mymms, Herts, United Kingdom.
authors: Bryony A
authors: BA
authors: Jones
authors: Carola
authors: C
authors: Sauter-Louis
authors: Joerg
authors: J
authors: Henning
authors: Alexander
authors: A
authors: Stoll
authors: Mirjam
authors: M
authors: Nielen
authors: Gerdien
authors: G
authors: Van Schaik
authors: Anja
authors: A
authors: Smolenaars
authors: Matthijs
authors: M
authors: Schouten
authors: Ingrid
authors: I
authors: den Uijl
authors: Christine
authors: C
authors: Fourichon
authors: Raphael
authors: R
authors: Guatteo
authors: Aurélien
authors: A
authors: Madouasse
authors: Simon
authors: S
authors: Nusinovici
authors: Piet
authors: P
authors: Deprez
authors: Sarne
authors: S
authors: De Vliegher
authors: Jozef
authors: J
authors: Laureyns
authors: Richard
authors: R
authors: Booth
authors: Jackie M
authors: JM
authors: Cardwell
authors: Dirk U
authors: DU
authors: Pfeiffer
mesh_terms: D000818:Animals; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000453:epidemiology / Q000517:prevention & control; D002417:Cattle; D030241:Diarrhea Virus 1, Bovine Viral; D005060:Europe / Q000453:epidemiology; D006470:Hemorrhage / Q000453:epidemiology / Q000517:prevention & control / Q000662:veterinary / Q000821:virology; D008954:Models, Biological; D010198:Pancytopenia / Q000453:epidemiology / Q000517:prevention & control / Q000662:veterinary / Q000821:virology; D014611:Vaccination / Q000379:methods; D014765:Viral Vaccines / Q000494:pharmacology
chemical_list: D014765:Viral Vaccines