Alpine ibex (Capra i. ibex) is not a reservoir for chlamydial infections of domestic ruminants and humans

Abstract

Chlamydophila (C.) abortus is the most common infectious abortigenic agent in small domestic ruminants in Switzerland. In contrast, the knowledge about chlamydiae in wild ruminants is scarce. As interactions between livestock and Alpine ibex (Capra i. ibex) occur on alpine pastures, the question raises if wild ruminants could play a role as carriers of chlamydiae. Thus, we investigated the prevalence of chlamydiae in Alpine ibex in Switzerland. In total, 624 sera, 676 eye swabs, 84 organ samples and 51 faecal samples from 664 ibex were investigated. Serum samples were tested by two commercial ELISA kits specific for C. abortus. Eye swabs, organs and faecal samples were examined by a Chlamydiaceae-specific real-time PCR. Positive cases were further investigated by the ArrayTube (AT) microarray method for chlamydial species determination. Of 624 serum samples investigated, 612 animals were negative, whereas nine sera (1.5%) reacted positively in one of the two tests and three sera showed an inconclusive result. Eye swabs of seven out of 412 ibex (1.7%) were tested positive for Chlamydiaceae by real-time PCR. By AT microarray, Chlamydophila pecorum was identified in two animals, Chlamydophila pneumoniae was detected in one animal and a mixed infection with Chlamydophila abortus and Chlamydophila pecorum was found in four animals. Organs and faecal samples were all negative by real-time PCR analysis. In summary, we conclude that C. abortus is not a common infectious agent in the Swiss ibex population. To our knowledge, this is the first description of C. pneumoniae in ibex. Further studies are necessary to elucidate the situation in other species of wild ruminants as chamois (Rupicapra r. rupicapra), red deer (Cervus elaphus) and roe deer (Capreolus c. capreolus) in Switzerland. (C.) abortus is the most common infectious abortigenic agent in small domestic ruminants in Switzerland. In contrast, the knowledge about chlamydiae in wild ruminants is scarce. As interactions between livestock and Alpine ibex (Capra i. ibex) occur on alpine pastures, the question raises if wild ruminants could play a role as carriers of chlamydiae. Thus, we investigated the prevalence of chlamydiae in Alpine ibex in Switzerland. In total, 624 sera, 676 eye swabs, 84 organ samples and 51 faecal samples from 664 ibex were investigated. Serum samples were tested by two commercial ELISA kits specific for C. abortus. Eye swabs, organs and faecal samples were examined by a Chlamydiaceae-specific real-time PCR. Positive cases were further investigated by the ArrayTube (AT) microarray method for chlamydial species determination. Of 624 serum samples investigated, 612 animals were negative, whereas nine sera (1.5%) reacted positively in one of the two tests and three sera showed an inconclusive result. Eye swabs of seven out of 412 ibex (1.7%) were tested positive for Chlamydiaceae by real-time PCR. By AT microarray, Chlamydophila pecorum was identified in two animals, Chlamydophila pneumoniae was detected in one animal and a mixed infec...

Occurrence of Chlamydiaceae, Mycoplasma Conjunctivae, and Pestiviruses in Alpine Chamois (Rupicapra r. Rupicapra) of Grisons, Switzerland

“…4 The question was raised whether wild ruminants play a role in the transmission of chlamydiosis. In a previous study, a low prevalence of Chlamydiaceae was demonstrated in Alpine ibex (Capra i. ibex) of Switzerland, 16 but the situation in other wild ruminants still remains to be elucidated. Alpine chamois (Rupicapra r. rupicapra) are known to be in contact with domestic sheep and goats on Alpine pastures 21 and could therefore possibly play a role in distribution and transmission of infectious diseases.…”

“…The DNA extraction was performed using a nucleic acid isolation system, a as previously described, 16 followed by real-time PCR for Chlamydiaceae on a commercial instrument b using the previously described 23S ribosomal RNA gene-based Chlamydiaceae family-specific real-time PCR.…”

Novel Sequence Types of Chlamydia pecorum Infect Free-Ranging Alpine Ibex (Capra ibex) and Red Deer (Cervus elaphus) in Switzerland

“…In livestock, C. pecorum may result in unapparent subclinical infections or may cause diseases including encephalomyelitis and polyarthritis (Jelocnik et al 2014). Chlamydia pecorum has recently been detected in several previously unrecognized wild hosts including water buffalo (Bubalus bubalis; Greco et al 2008), Alpine ibex (Capra ibex; Holzwarth et al 2011a), chamois (Rupicapra r. Rupicapra; Holzwarth et al 2011b), red deer (Cervus elaphus; Regenscheit et al 2012), and birds (Frutos et al 2012).…”

“…The initial collection (Table 1) targeted in this study consisted of a previously screened cohort of ocular swabs collected from six hunted ibex (n57; both eyes from one animal; Holzwarth et al 2011a) and a chamois (n51; Holzwarth et al 2011b) and a fecal sample from a hunted red deer (Regenscheit et al 2012). The chamois had corneal lesions and blindness; the other animals had no clinical signs of disease.…”

“…The study centered on the canton of Grisons, Switzerland, where cograzing of wildlife and domesticated ruminants is common and where C. pecorum was identified in ibex (Holzwarth et al 2011a), chamois (Holzwarth et al 2011b), and red deer (Regenscheit et al 2012). Molecular typing of these C. pecorum-positive samples from both of these groups from the sympatric populations was not performed at the time and will be necessary to evaluate whether any ''spill-over'' or ''spill-back'' has occurred between the populations.…”