Isolated Bacteria from the Uteri of Camels with Different Reproductive Backgrounds: A Study on Sampling Methodology, Prevalence, and Clinical Significance

SIMPLE SUMMARY: The mammalian uterus has been shown to host a range of microorganisms with or without potential pathogenic capacity. In camels, microorganisms from infertile subjects have been isolated using various sampling methodologies, but not much is known about the range of expected microbes that can be harbored in the uteri of camels without a complicated reproductive performance. The current results indicated up to 66% of camels yield bacteria from uterine samples with a higher frequency among sub-fertile subjects; yet, uterine bacterial burden does not necessarily indicate uterine pathology in otherwise reproductively asymptomatic animals. The application of small-volume lavage for uterine sampling might change our understanding about the range of uterine isolates in camels. ABSTRACT: The objectives of this study were to comparatively identify the common bacterial isolates from the uteri of camels coming from different reproductive backgrounds after standardizing the sampling method and to investigate the association of clinically measurable parameters with uterine colonization by these isolates. The uterine samples from 856 dromedary camels yielded a total of 17 different bacterial species with a higher proportion of sub-fertile camel uteri being colonized by bacteria (66.6%) as compared to nulliparous, recently calved, and those with unknown reproductive history combined (44.2%; p < 0.05). Camels with body condition scoring < 3 and those with a consistently echogenic appearance of the uterine lumen by sonography were more likely to be positive on uterine culture, while the presence of pus in uterine discharge was not associated with the odds of bacterial isolation (p > 0.05). While certain strains were more likely to be obtained from the uteri of the sub-fertile group (p < 0.05), embryo transfer to camels with a positive uterine culture in the absence of other gross reproductive pathologies did not necessarily affect the overall pregnancy rate compared to recipients with a negative uterine culture (p > 0.05). In conclusion, a relatively high bacterial load can be identified from the uteri of both sub-fertile and normal dromedary camels, with a higher frequency among the former. The uterine ultrasonography and evaluation of the body condition score can help in identifying the camels in which uterus is contaminated by bacteria.