Assessment of mastitis in camel using high-throughput sequencing

Abstract

Camel milk is recognized as a functional food with significant economic value. Mastitis is one of the most common and costly diseases in the dairy industry. Mastitis, which is caused by pathogens such as bacteria, viruses, fungi, and algae, has an impact on the quality and quantity of milk produced as well as animal health and welfare. There is a paucity of data on the etiological factors that cause camel mastitis. This study reports the bacterial and fungal community involved in clinical camel mastitis using Illumina amplicon sequencing. A total of 25 milk samples were analyzed, including 9 samples with mastitis and 16 healthy samples. The bacterial community in healthy samples was significantly more diverse and abundant than in mastitis samples. The fungal population in mastitis samples, on the other hand, was more diverse and abundant. As compared to healthy samples, the genera Staphylococcus, Streptococcus, Schlegelella, unclassified Enterobacteriaceae, Lactococcus, Jeotgalicoccus. and Klebsiella were found to be abundant in mastitic milk. However, the genera Corynebacterium, Enteractinococcus, unclassified Sphingomonadaceae, Atopostipes, Paenibacillus, Pseudomonas, Lactobacillus, Sphingomonas, Pediococcus and Moraxella were reduced. In the fungal community, mastitis caused a significant increase in the relative abundance of the majority of taxa, including Candida, Phanerochaete, Aspergillus, Cladosporium and unclassified Pyronemataceae, while Penicillium and Alternaria showed a decline in relative abundance. In the bacterial and fungal communities, the discriminant analysis showed 19 and 5 differently abundant genera in healthy milk and mastitic milk, respectively. In conclusion, this study showed a microbiome dysbiosis linked to clinical camel mastitis, with opportunistic pathogens outgrowing commensal bacteria that were reduced. These findings are essential in designing an appropriate control program in the camel dairy herd, as well as in preventing and treating camel mastitis.