Vetmeduni: Bacterium identified as a potential cause of miscarriages in pigs
A research team at the University of Veterinary Medicine Vienna has provided further evidence in a recent study that Trueperella abortisuis may be involved in reproductive disorders and abortions in pigs. Both a case report on an infected pregnant sow and the analysis of routine data indicate that this hitherto understudied bacterium should be more strongly considered in cases of reproductive failure in pigs. Based on the study findings, the researchers recommend including the bacterium in the differential diagnosis of sow abortions in the future.
The investigation centers on a sow that aborted eleven fetuses on the 100th day of gestation. In most fetuses, high levels of Trueperella abortisuis were isolated from gastric contents, umbilical cord blood, and amniotic fluid. Seven fetuses exhibited severe purulent bronchopneumonia. In four placentas, a necrotizing-purulent placentitis with gram-positive bacteria in the lesions was observed. Common viral and bacterial causes of abortion were ruled out by PCR.
Evidence of Fetal Infection and Placentitis
“The combination of fetal infection, characteristic lesions in the lungs and placenta, and the detection of high loads of T. abortisuis provides an important indication of a possible causal role of this pathogen in the abortion,” emphasizes lead author Lukas Schwarz from the Clinical Center for Population Medicine in Fish, Pig and Poultry. While these findings do not constitute definitive proof of sole causality, they reinforce observations reported by other research groups.
Routine Data Corroborate Diagnostic Clues from the Individual Case
To better contextualize this individual case, the researchers also analyzed Austrian diagnostic data routinely collected at Vetmeduni from 2019 to 2025. T. abortisuis was detected in 31 samples from 14 farms. The samples originated predominantly from the genital tract and abortion material. Notably, consistently high bacterial concentrations were found in pooled fetal gastric contents. Common viral and bacterial abortion agents were excluded by PCR. “Our retrospective data show that T. abortisuis is not limited to an isolated case. Its repeated detection in connection with abortion material and samples from the genital tract makes this pathogen relevant for differential diagnosis,” explains Lukas Schwarz.
New Detections Require Ongoing Surveillance and Further Research
The results provide important new evidence for the abortifacient potential of T. abortisuis. Accordingly, Lukas Schwarz and his colleagues recommend “considering T. abortisuis in the workup of reproductive disorders and abortions in sows going forward. At the same time, further studies are needed to better understand the bacterium’s pathogenicity and its interactions with other microorganisms of the reproductive tract.”
In this context, the researchers underscore the importance of continuous monitoring of breeding herds. Further studies should determine under which conditions T. abortisuis causes disease, what interactions exist with the bacterial flora of the genital tract, and what significance the pathogen holds for the reproductive health of pig herds.
The article „Late-term abortion associated with Trueperella abortisuis in Austria: a case report combined with six years of retrospective diagnostic data“ by Lukas Schwarz, Christine Unterweger, Igor Loncaric, Rene Brunthaler, Heinrich Kreutzmann, Anja Joachim, Barbara Hinney and Andrea Buzanich-Ladinig was published in „BMC Veterinary Research“.
Kontakt
Dr.med.vet. Lukas Schwarz
Klinisches Zentrum für Populationsmedizin bei Fisch, Schwein und Geflügel
Veterinärmedizinische Universität Wien (Vetmeduni)
Lukas.Schwarz@vetmeduni.ac.at