Mycoplasma conjunctivae-Associated Keratoconjunctivitis in Norwegian Muskox (Ovibos moschatus)

Wildlife-Livestock Host Community Maintains Simultaneous Epidemiologic Cycles of Mycoplasma conjunctivae in a Mountain Ecosystem

Infectious keratoconjunctivitis (IKC) is an eye disease caused by Mycoplasma conjunctivae that affects domestic and wild caprines, including Iberian ibex (Capra pyrenaica), a medium-sized mountain ungulate. However, its role in IKC dynamics in multi-host communities has been poorly studied. This study assessed M. conjunctivae in Iberian ibex and seasonally sympatric domestic small ruminants in the Natural Space of Sierra Nevada (NSSN), a mountain habitat in southern Spain. From 2015 to 2017, eye swabs were collected from 147 ibexes (46 subadults, 101 adults) and 169 adult domestic small ruminants (101 sheep, 68 goats). Mycoplasma conjunctivae was investigated through real-time qPCR and statistically assessed according to species, sex, age category, year, period, and area. The lppS gene of M. conjunctivae was sequenced and phylogenetically analysed. Mycoplasma conjunctivae was endemic and asymptomatic in the host community of the NSSN. Three genetic clusters were shared by ibex and livestock, and one was identified only in sheep, although each host species could maintain the infection independently. Naïve subadults maintained endemic infection in Iberian ibex, with an epizootic outbreak in 2017 when the infection spread to adults. Wild ungulates are epidemiologically key in maintaining and spreading IKC and other shared diseases among spatially segregated livestock flocks.

Bacteria associated with infectious keratoconjunctivitis outbreak in confined lambs

Introduction. Infectious keratoconjunctivitis is a significant ocular disease found in confined sheep. Little information about the aetiological agents and their antimicrobial susceptibility is available.Gap Statement. There is limited information on the aetiological agents involved in keratoconjunctivitis outbreaks in sheep.Aim. The present research aimed to determine the bacterial aetiological factors involved in an outbreak of infectious keratoconjunctivitis in confined lambs.Methodology. Ocular swabs were collected from 23 randomly selected lambs, which were classified into three groups according to the severity of the lesion: group I (N=6; no ocular involvement), group II (N=8; less severe injuries) and group III (N=9; more severe injuries). Isolation of aerobic bacteria and antimicrobial susceptibility tests were carried out. Molecular detection of Mollicutes was performed, and positive samples were tested to confirm the presence of the following species: Mycoplasma conjunctivae, Mycoplasma agalactiae and Mycoplasma mycoides subsp. capri.Results. Moraxella sp. and Mollicutes were detected in all groups, but we inferred that Moraxella sp. are only significant in the early stages of the disease. M. conjunctivae was detected in all tested groups, while M. agalactiae was detected in samples of group III only. One strain of Moraxella sp. was resistant to erythromycin and showed intermedite resistance to tetracycline.Conclusion. The presence of these species confirms their importance in the aetiology of this disease, and the low resistance profile observed in the studied farm suggested an increased cure success rate.