Hemoplasmas and ticks in cattle from Somalia

Abstract

Hemotropic mycoplasmas (hemoplasmas) are small Gram-negative bacteria that parasitize red blood cells and can cause mild to severe anemia in a wide range of vertebrates, including ruminants. Cattle population in Somalia is around 3.9 million heads, with animals more concentrated around the river areas, mainly in the Juba River and Shabelle River Valleys. Information on hemoplasmas in Sub-Saharan Africa are scarce, mainly in Somalia, where no studies have been performed to date. Accordingly, this study aimed to assess the molecular occurrence of hemoplasmas in 131 cattle blood samples from Somalia. Thirty out of 131 (22.90%; 95% CI: 16.54-30.81%) cattle were infested by ticks: Rhipicephalus pulchellus (68.18%), Amblyomma gemma (18.18%), Amblyomma lepidum (9.09%), Hyalomma marginatum (1.51%), Hyalmomma rufipes (1.51%), and Rhipicephalus pravus (1.51%). A total of 74/131 (56.48%; 95% CI: 47.93-64.67%) cattle were positive for hemotropic Mycoplasma spp. by real-time PCR (qPCR) based on the 16S rRNA gene. Hemoplasma-positive samples were later subjected to species-specific PCR assays for Mycoplasma wenyonii and 'Candidatus Mycoplasma haematobovis' based on the 16S rRNA gene. A total of 34/74 (45.94%; 95% CI: 35.07-57.22%) animals were coinfected by both species; 31/74 (41.89%; 95% CI: 31.32-53.26%) and 3/74 (4.05%; 95% CI: 01.39-11.25%) cattle were solely positive to M. wenyonii and 'Ca. M. haematobovis', respectively. Six out of 74 (8.1%; 95% CI: 03.77-16.58%) cattle were negative on species-specific conventional PCR assays but tested positive by a semi-nested PCR assay based on the 16S rRNA gene of hemoplasmas. Sequencing of the detected hemotropic Mycoplasma sp. 16S rRNA gene confirmed that animals were infected by M. wenyonii and 'Ca. M. haematobovis'. To the best of our knowledge, this is the first study on the detection of hemoplasmas in cattle from Somalia.

Keywords: Bovine; Hemotropic mycoplasmas; Mycoplasma wenyonii; Sub-Saharan Africa; ‘Candidatus Mycoplasma haematobovis.