<i>Anaplasma phagocytophilum</i> and <i>Anaplasma ovis</i>–Emerging Pathogens in the German Sheep Population

oleh: Benjamin Ulrich Bauer, Cristian Răileanu, Oliver Tauchmann, Susanne Fischer, Christina Ambros, Cornelia Silaghi, Martin Ganter

Format: Article
Diterbitkan: MDPI AG 2021-10-01

Deskripsi

Knowledge on the occurrence of pathogenic tick-borne bacteria <i>Anaplasma phagocytophilum</i> and <i>Anaplasma ovis</i> is scarce in sheep from Germany. In 2020, owners from five flocks reported ill thrift lambs and ewes with tick infestation. Out of 67 affected sheep, 55 animals were clinically examined and hematological values, blood chemistry and fecal examinations were performed to investigate the underlying disease causes. Serological tests (cELISA, IFAT) and qPCR were applied to all affected sheep to rule out <i>A. phagocytophilum</i> and <i>A. ovis</i> as a differential diagnosis. Ticks were collected from selected pastures and tested by qPCR. Most animals (<i>n</i> = 43) suffered from selenium deficiency and endoparasites were detected in each flock. <i>Anaplasma</i> spp. antibodies were determined in 59% of examined sheep. Seventeen animals tested positive for <i>A. phagocytophilum</i> by qPCR from all flocks and <i>A. phagocytophilum</i> was also detected in eight pools of <i>Ixodes ricinus</i>. <i>Anaplasma phagocytophilum</i> isolates from sheep and ticks were genotyped using three genes (<i>16S rRNA</i>, msp4 and groEL). <i>Anaplasma ovis</i> DNA was identified in six animals from one flock. Clinical, hematological and biochemical changes were not significantly associated with <i>Anaplasma</i> spp. infection. The <i>16S rRNA</i> analysis revealed known variants of <i>A. phagocytophilum</i>, whereas the msp4 and groEL showed new genotypes. Further investigations are necessary to evaluate the dissemination and health impact of both pathogens in the German sheep population particularly in case of comorbidities.