Introduction
The dromedary (Camelus dromedarius  or one-humped camel), named in 1758 by the Swedish zoologist Carl Linnaeus (Linnaeus, 1758), is one of a half-dozen of camel species left on the planet, including llamas, alpacas, vicunas, and guanacos in South America, as well as its cousin, the two-humped Bactrian camel in Asia (Hirst, 2020). All evolved from a common ancestor some 40-45 million years ago in North America (Hirst, 2020). Archaeological evidence for early dromedary use, includes the predynastic site of Qasr Ibrim, in Egypt (Hirst, 2020), where camel dung was identified about 900 BC, and because of its location interpreted as dromedary. Dromedaries, did not become ubiquitous in the Nile Valley until about 1,000 years later (Hirst, 2020). Nowadays, the camels reach Egypt in herds through the continuous importation, mainly from Chad, Sudan, Ethopia, Eritria, Somalia and Libya becoming a crucial cause of transmission of infectious diseases (Roess et al., 2015; Napp et al., 2018).
Mycoplasma bovis is a wall-less bacterium, which is considered one of the most pathogenic species of the genus Mycoplasma in the family of Mycoplasmataceae within the Class Mollicutes (Brown et al., 2015). To date there have been few studies investigating mycoplasmosis in camel species caused by M. bovis although it is an important cause of respiratory disease and mastitis in cattle throughout the world, and often is reported as emerging (Gille et al., 2018). While M. bovis  is not a risk for food safety (Nigel French, 2019), it can cause a disease that affects animal welfare, sustainable food production and the farming economy. Consequently, M. bovis is one of the major pathogens of biosecurity significance to a dairy herd, due to its highly contagious nature and tendency to be chronic, debilitating and unresponsive to antimicrobial therapy (Fox, 2012). In Africa, camels live as free ranging animals and there are no official restrictions on animal movement between the African countries; a situation also seen within the European Union (EU) with cattle (Calcutt et al., 2018).
In vitro  phenotypes linked to the virulence of M. bovis  strains isolated from camels have not yet been described despite its pathogenic potential which has been evidenced in several studies (Nicholas and Ayling, 2003). Großhennig et al. (2016) and Osman et al. (2020) shared results confirming H2S production and haemolysis were correlated in M. pneumonia and M. arginini . In this study we carried out a knowledge gap analysis, by the assessment of H2S production by M. bovis as a potential virulence factor in addition to the haemolytic activity; its ability to produce biofilm and identification of two genes responsible for quinolone resistance (QRDR). We have also investigated whethervsp -related DNA sequences also occur in M. bovis camel isolates.