Detection of infectious agents in equine pregnancy loss, stillbirth and neonatal death

Equine abortion, stillbirth and neonatal death cause major economic losses to the equine in-dustry worldwide. Both non-infectious and a wide range of infectious causes have been described. However, the relative contribution of pathogens to equine abortion, stillbirth and neonatal death is poorly documented, since available studies involve only a limited number of pathogens. There-fore, the objectives of the present retrospective monitoring study were to determine the preva-lence of infectious agents associated with equine abortion and perinatal mortality in Belgium, and to set up a protocol usable under field conditions using polymerase chain reaction targeting. A real-time simple polymerase chain reaction for eight different abortifacient pathogens was conducted leading to the detection of at least one infectious agent in 37% of 105 analyzed cases. In the diagnosed cases, equine herpesvirus-1 was the most detected pathogen (49%), followed by Streptococcus equi subspecies zooepidemicus (28%), Coxiella burnetii (18%), Leptospira interro-gans (3%) and Neospora caninum (3%). None of the analyzed cases was positive for equine viral arteritis, equine herpesvirus-4 and Chlamydophila spp. In this study, PCR targeting is shown to have its value to detect a (co)-infectious cause in equine abortion, stillbirth and neonatal death, especially in field conditions where autolysis and contamination might preclude a full post-mortem examination protocol based on classical micro-biological examination.