ORIGINAL RESEARCH article
Front. Vet. Sci.
Sec. Veterinary Infectious Diseases
This article is part of the Research TopicStudy on Pathogenesis and Prevention of Ruminant Viral DiseasesView all 3 articles
Maedi-visna infection in Pomeranian Coarsewool sheep in Germany: seroprevalence, environmental and genetic risk factors
Provisionally accepted
- 1Tierarztliche Hochschule Hannover, Hanover, Germany
- 2Istituto Zooprofilattico Sperimentale dell'Umbria e delle Marche Togo Rosati, Perugia, Italy
- 3Justus-Liebig-Universitat Giessen, Giessen, Germany
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Small ruminant lentiviruses (SRLV) cause maedi-visna (MV), an incurable, wasting disease, affecting sheep worldwide. This study evaluated the seroprevalence of the maedi-visna virus (MVV) in the native German sheep breed Pomeranian Coarsewool Sheep (RPL) and environmental and genetic risk factors for individual and flock-level seropositivity. A total of 849 samples from 35 farms across nine German states were analyzed for MVV antibodies with an enzyme-linked immunosorbent assay (ELISA). Individual seroprevalence and clinical prevalence incidence were 3.5% (30/849) and 13.3% (4/30), respectively. Seropositive sheep were detected in six flocks, with prevalences between 5.3% and 37.5%. Flocks in Eastern Germany and sheep older than three years showed the highest seroprevalence. Purchase of ewes was the main environmental risk factor for seropositivity. ELISA-based serotyping of SRLV in the MVV-positive sheep identified, besides genotype A, for the first time in Germany genotypes B and E, whereas molecular genotyping, based on Sanger sequencing, identified only genotype A (A1, A3, A8, and A21, and A21-like). Apart from the obvious inconsistencies between the results of these two methods, the presence of different viral sero-or genotypes suggest multiple virus introduction routes. Sequencing of exons 2 and 3 of the transmembrane protein 154 gene (TMEM154) of 530 sheep revealed non-synonymous variation at codons 35, 44 (known to be in linkage with a frame-shift variant coded in exon 1), and 70. Analysis of association between the putatively protective TMEM154 codon 35 genotype KK and MVV seropositivity showed only a tendency towards significance (p=0.088), whereas seroprevalence was significantly (p=0.001) lower in sheep exclusively carrying the K allele at codon 35 and/or the M allele at codon 44. In contrast, MVV seropositivity was significantly higher in sheep with one or two I alleles at codon 70 (p=0.045). Despite a low seroprevalence in the RPL breed in Germany, regular MVV monitoring is strongly recommended to avoid its spread. An eradication program based on serological testing and the removal of seropositive sheep should be implemented. Selection for certain TMEM154 alleles in affected flocks could support eradication measures, but their effect on MVV susceptibility in this breed requires further investigation.
Keywords: Small Ruminant Lentivirus, Maedi-visna virus, Pomeranian Coarsewool sheep, seroprevalence, risk factor, TMEM154, ELISA, Germany
Received: 18 Sep 2025; Accepted: 03 Nov 2025.
Copyright: © 2025 Frölich, Beato, Gobbi, Mrabet, Lühken and Ganter. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Cassandra Frölich, cassandra.froelich@tiho-hannover.de
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.