Skip to main content

Table 6 Cause-of-death and diagnostic case definitions for infectious causes of bovine perinatal mortality

From: Investigation of bovine abortion and stillbirth/perinatal mortality - similar diagnostic challenges, different approaches

Cause-of-death Sub-category Case definition Diagnostic criteria
Infection Foetopathogenic bacteria Infection with a significant bacterium: Bacillus licheniformis, Campylobacter foetus, Listeria monocytogenes, Salmonella Dublin, Trueperella pyogenes, etc Pure heavy growth in culture of pathogenic species from abomasal contents/foetal tissues or nearly pure/mixed growth with associated lesions consistent with foetal sepsis/placentitis (in particular for potential contaminants, e.g. E. coli). If isolated from placenta only, associated intra-lesional bacterial placentitis.
  Chlamydophilia/Parachlamydiacae Detection of organism in the placenta, foetal tissue or abomasal contents (e.g. MZN smear, PCR, IHC) confirmed by histopathology
  Coxiella burnetii Detection of organism in the placenta, foetal tissue or abomasal contents (e.g. MZN smear, PCR, IHC) confirmed by histopathological lesions (e.g. necrotising placentitis); Detection of the organism in the absence of lesions indicates very acute recent infection.
  Leptospira spp (e.g. Hardjo, Grippotyphosa, Australis) Detection of pathogenic antigen (e.g. PCR/FAT/IHC-positive) in foetal tissues (e.g. kidney, spleen) with accompanying lesions or detection of high foetal antibody titre indicating recent infection
Foetopathogenic fungi Aspergillus app, zygomycetes, yeasts, etc Detection of fungal hyphea in abomasal contents/placenta (e.g. wet prep, culture) with associated gross/histopathology lesions (e.g. foetal dermatitis, IUGR, placentitis, hepatomegaly)
Foetopathogenic parasite Neospora caninum Detection of histological lesions (characteristic neuropathology, myocardial necrosis, multifocal placentitis; cause) and the parasite antigen in foetal tissues (e.g. PCR; infection) +/− foetal antibodies (exposure)
Foetopathogenic viruses BoHV-I, 4 Detection of viral antigen in foetal tissues (e.g. liver, spleen, adrenal) +/− lesions, e.g. focal necrotising hepatitis, placentitis
  BVDv Detection of viral antigen in foetal tissues (e.g. spleen, thymus, adrenal, ear) and gross/histopathology lesions
  SBV Detection of two or more syndromic gross lesions (arthrogryposis, hydranencephaly, torticollis, scoliosis, kyphosis, brachygnathia inferior) and foetal antigen (e.g. PCR).
Infectious lesions Compelling lesions indicative of infection Gross/histological lesions consistent with exposure/response to infection e.g. pericarditis, meningoencephalitis, enteritis omphalo-peritonitis, pleuropneumonia, lymphadenomegaly, systemic sepsis (lesions in at least two organs) and placentitis.