Isolation and Whole Genome Sequence Analysis of Cow Mastitis Candida tropicalis

Abstract

Abstract Candida tropicalis（C. tropicalis）is a zoonotic pathogen that is widespread in the environment and in recent years an increasing number of dairy cows have been infected with the fungus causing mastitis in cows. In this study, the pathogenic bacteria were isolated from the milk of cows with mastitis and their pathogenicity and drug resistance were investigated. Firstly, we identified pathogenic species through bacterial morphological isolation, then used genome sequencing technology to analyze and predict pathogenicity and drug resistance of pathogens, then verified the virulence of pathogens by infecting mice, and finally verified the drug resistance of pathogens through drug sensitivity tests and PCR technology. Our results show that the causative agent of mastitis in cows in this study is C. tropicalis, and genome sequencing analysis indicates that the organism is highly virulent and multi-drug resistant, and is capable of causing organ damage in mice. C. tropicalis is highly sensitive to nystatin and ketoconazole, moderately sensitive to amphotericin B and insensitive to itraconazole, gentamicin, penicillin and ciprofloxacin, and the present study screened for drug resistance genes such as ABC1, CDR1 and CDR2. In conclusion, the C. tropicalis in this study was highly pathogenic and multi-drug resistant. This study provides a theoretical basis for further screening of novel drug resistance genes in C. tropicalis and provides some reference for the selection of drugs for the treatment of fungal dairy mastitis.