Bacterial, fungal, parasitological and pathological analyses of abortions in small ruminants from 2012-2016

Abstract

Abortion in small ruminants presents a clinical and economic problem with legal implications regarding animal health and zoonotic risk by some of the abortive pathogens. Several bacteria, fungi and parasites can cause abortion, but cost-orientated routine diagnostics only cover the most relevant epizootic agents. To cover a broad-range of common as well as underdiagnosed abortifacients, we studied 41 ovine and 36 caprine abortions by Stamp's modification of the Ziehl-Neelsen stain, culture for classical and opportunistic abortive agents, real-time PCR for C. burnetii, C. abortus, pathogenic Leptospira spp., Toxoplasma gondii and Neospora caninum. When the dam's serum was available detection of antibodies against B. melitensis, C. burnetii, C. abortus and Leptospira spp. was performed. In 37 cases sufficient placental tissue was available for pathological and histopathological examination. From the 77 cases 11 (14.3%) were positive by staining whereas real-time PCR detected C. burnetii and C. abortus in 49.3% and 32.5% of the cases. Antibodies against C. abortus and Leptospira spp. (33.3 and 26.7%) were detected. In 23.4% a bacterial culturable pathogen was isolated. Fungal abortion was confirmed in 1.3% of cases. A single abortive agent was identified in 44.2% of the cases and in 31.2% multiple possible abortifacients were present. Our study shows that the highest clarification rate can only be achieved by a combination of methods and evidences the role that multi-infections play as cause of abortion.

Limited added value of fungal ITS amplicon sequencing in the study of bovine abortion

“…This has been previously discussed, e.g. co-infections with C. abortus , Parachlamydia , N. caninum or BVD ( Blumer et al., 2011 ; Schnydrig et al., 2017 ; Vidal et al. 2017a , b ) and investigations are underway to study host-pathogen interaction, e.g.…”

“…fetus . Although co-infections as a cause of abortion in ruminants have been observed ( Blumer et al., 2011 ; Schnydrig et al., 2017 ; Vidal et al., 2017a , 2017b ), the underlying mechanisms are not yet understood.…”

“…For all samples, including those from control fetuses [PL (n = 75), AC (n = 66), AF (n = 3), liver (n = 61), lung (n = 61)], broad-spectrum bacterial and fungal culture was performed according to Schnydrig et al. (2017) .…”

An Accessible Diagnostic Toolbox to Detect Bacterial Causes of Ovine and Caprine Abortion

“…Abortion, the expulsion of a fetus that is incapable of independent life, premature birth, the expulsion before full term of a fetus capable of independent life, and stillbirth, the expulsion of a dead full-term fetus, together are here referred to as abortion [ 1 ]. In small ruminants, abortion can be caused by various non-infectious and infectious agents, and several of these infectious agents constitute a zoonotic risk [ 2 ]. As a consequence, abortion not only results in reproductive losses and economic damage, and concerns about the possible disease for the owner, his family, farm visitors, and, when Coxiella burnetii is involved, people living in the surroundings [ 3 , 4 ].…”

Serological detection of anti-leptospiral antibodies in outdoor cats in Switzerland

“…Leptospirosis is endemic in Switzerland causing acute systemic disease in dogs ( Major, Schweighauser, & Francey, 2014 ), beavers ( Marreros et al., 2018 ) and sporadically humans ( Schreiber et al., 2015 ) and abortion in livestock ( Schnydrig et al., 2017 , Vidal et al., 2015 ). In Swiss dogs, a dramatic increase in the incidence of acute leptospirosis was documented between 2003 and 2012 ( Major et al., 2014 ).…”