Gut Microbial Alterations in Diarrheal Baer's Pochards (Aythya baeri)

The structure and composition of gut microbiota correlate with the occurrence and development of host health and disease. Diarrhea can cause alterations in gut microbiota in animals, and the changes in the gut microbial structure and composition may affect the development of diarrhea. However, there is a scarcity of information on the effects of diarrhea on gut fungal composition and structure, particularly in Baer's pochard (Aythya baeri). The current study was performed for high-throughput sequencing of the fungal-specific internal transcribed spacer 1 (ITS-1) to detect the differences of gut mycobiota in healthy and diarrheal Baer's pochard. Results showed that the gut mycobiota not only decreased significantly in diversity but also in structure and composition. Statistical analysis between two groups revealed a significant decrease in the abundance of phylum Rozellomycota, Zoopagomycota, Mortierellomycota, and Kickxellomycota in diarrheal Baer's pochard. At the genus levels, fungal relative abundance changed significantly in 95 genera, with 56 fungal genera, such as Wickerhamomyces, Alternaria, Penicillium, Cystofilobasidium, and Filobasidium, increasing significantly in the gut of the diarrheal Baer's pochard. In conclusion, the current study revealed the discrepancy in the gut fungal diversity and community composition between the healthy and diarrheal Baer's pochard, laying the basis for elucidating the relationship between diarrhea and the gut mycobiota in Baer's pochard.

The A756T Mutation of the ERG11 Gene Associated With Resistance to Itraconazole in Candida Krusei Isolated From Mycotic Mastitis of Cows

Candida krusei (C. krusei) has been recently recognized as an important pathogen involved in mycotic mastitis of cows. The phenotypic and molecular characteristics of 15 C. krusei clinical isolates collected from cows with clinical mastitis in three herds of Yinchuan, Ningxia, were identified by matrix-assisted laser desorption ionization–time of flight mass spectrometry. In addition to sequencing analysis, the ERG11 gene that encodes 14α-demethylases, the expression of the ERG11 gene, and efflux transporters ABC1 and ABC2 in itraconazole-susceptible (S), itraconazole-susceptible dose dependent (SDD), and itraconazole-resistant (R) C. krusei isolates was also quantified by a quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) assay. Sequencing analysis revealed three synonymous codon substitutions of the ERG11 gene including T939C, A756T, and T642C in these C. krusei clinical isolates. Among them, T642C and T939C mutations were detected in itraconazole-resistant and -susceptible C. krusei isolates, but the A756T substitution was found only in itraconazole-resistant isolates. Importantly, the expression of the ERG11 gene in itraconazole-resistant isolates was significantly higher compared with itraconazole-SDD and itraconazole-susceptible isolates (p = 0.052 and p = 0.012, respectively), as determined by the qRT-PCR assay. Interestingly, the expression of the ABC2 gene was also significantly higher in itraconazole-resistant isolates relative to the itraconazole-SDD and itraconazole-susceptible strains. Notably, the expression of ERG11 was positively associated with resistance to itraconazole (p = 0.4177 in SDD compared with S, p = 0.0107 in SDD with R, and p = 0.0035 in S with R, respectively). These data demonstrated that mutations of the ERG11 gene were involved in drug resistance in C. krusei. The A756T synonymous codon substitution of the ERG11 gene was correlated with an increased expression of drug-resistant genes including ERG11 and ABC2 in itraconazole-resistant C. krusei isolates examined in this study.

Chronic incurable mastitis in sheep: prevalence, identification of predisposing factors, and genotyping of fungal causative species using PCR-RFLP

Mycotic mastitis is a neglected problem type of incurable chronic mastitis in sheep flock of many countries which associated with wide economic burden. In the current study, a total of 600 ewes at Menofia governorate, Egypt, were subjected to clinical and molecular examination using PCR-RFLP to estimate the prevalence of chronic mycotic mastitis and identify the causative agent. A structured questionnaire is distributed to shepherds in the study area to identify the risky behavioral practices being followed and lead to increase the prevalence of mycotic mastitis cases. The results showed that out of 600 ewes examined, 150 showed clinical signs of mastitis (25%). A total of 25 ewes with clinical mastitis did not respond to antibiotic treatment for long time and suffered from mycotic mastitis (16.7%, CI 11.1-23.6%). A total of 31 fungal isolates were identified: 14 yeast spp., Candida albicans, Candida parapasilosis, Candida rugosa, and Saccharomyces spp. and 17 mold spp., Alternaria spp., and Fusarium spp. Results showed also the widespread of risky practices among shepherds which could be responsible for the increase the prevalence of mycotic mastitis among ewes in the study area including presenting of decayed food to sheep, uncontrolled usage of antibiotics for mastitis treatment, lack of usage of antiseptics, and keeping of chronic infected animals in flocks for breeding. In conclusions, using of specific ITS1 and ITS4 primer sets with PCR-RFLP technique provided a suitable method for rapid identification and genotyping of Candida spp., Scaccharomyces, Alternaria, and Fusarium vertolliodes isolated from chronic mastitis in sheep. Furthermore, this study is considered up to our knowledge one of scarce estimates available on mycotic mastitis in sheep flocks in Egypt. Mycotic mastitis existed at higher prevalence estimates in the study area and educational campaigns to shepherds are much required to increase their awareness on the threat of risky of behaviors responsible for spread of the disease among their animals.

Epidemiological investigation of non-albicans Candida species recovered from mycotic mastitis of cows in Yinchuan, Ningxia of China

BACKGROUND

Candida spp. is the vital pathogen involved in mycotic mastitis of cows. However the epidemiology and infection of Candida species in mycotic mastitis of cow in Ningxia province of China has not been explored. In the present study, the epidemiology, antimicrobial susceptibility and virulence-related genes of non-albicans Candida (NAC) species were investigated.

METHODS

A total of 482 milk samples from cows with clinical mastitis in four herds of Yinchuan, Ningxia were collected and used for the isolation and identification of mastic pathogens by phenotypic and molecular characteristics, and matrix-assisted laser desorption ionization-time of flight mass spectrometry. The antimicrobial susceptibility to antifungal agents was also determined by a disk diffusion assay. The presence of virulence-related genes was determined by polymerase chain reaction (PCR).

RESULTS

A total of 60 isolates from nine different Candida species were identified from 256 (60/256, 23.44%) milk samples. The most frequently identified species in cows with clinical mastitis groups were Candida krusei (n = 14) and Candida parapsilosis (n = 6). Others include Candida lipolytica, Candida lusitaniae, Cryptococcus neoformans. But no Candida albicans was identified in this study. Interestingly, All C. krusei isolates (14/14) were resistant to fluconazole, fluorocytosine, itraconazole and ketoconazole, 2 out of 14 C. krusei were resistant to amphotericin, and 8 out of the 14 were resistant to nystatin. Similarly, all six C. parapsilosis isolates were resistant to fluorocytosine, but susceptible to fluconazole, ketoconazole and nystatin; two of the six were resistant amphotericin and itraconazole. Molecularly, all of the C. parapsilosis isolates carried eight virulence-related genes, FKS1, FKS2, FKS3, SAP1, SAP2, CDR1, ERG11 and MDR1. All of the C. krusei isolates contained three virulence-related genes, ERG11, ABC2 and FKS1.

CONCLUSION

These data suggested that Candida species other than C. albicans played a pathogenic role in mycotic mastitis of cows in Yinchuan, Ningxia of China. The high incidence of drug-resistant genes in C. parapsilosis and C. krusei also highlighted a great concern in public and animal health in this region.

Short communication: The first report of Cyberlindnera rhodanensis associated with clinical bovine mastitis

An acute case of clinical mastitis in a Holstein cow from second lactation is reported here. A milk sample from the affected quarter was cultured on 5% bovine blood agar and incubated at 37°C for 72 h. After 24 h of incubation, numerous colonies of yeast were observed: the Candida characteristic was not detected by CHROMagar Candida (Difco, Franklin Lakes, NJ). The DNA extraction of the isolate was performed, and DNA was subjected to amplification and sequencing of the D1/D2 region of the large subunit rRNA gene. The sequences were aligned using Mega 7.0 and used for searching GenBank by BLASTn (Basic Local Alignment Search Tool for nucleotides), revealing 98% of identity with Cyberlindnera rhodanensis. To date, this is the first report of this yeast associated with clinical bovine mastitis.

Scientific Opinion on the update of the list of QPS-recommended biological agents intentionally added to food or feed as notified to EFSA

EFSA is requested to assess the safety of a broad range of biological agents in the context of notification for market authorisation as sources of food and feed additives, food enzymes and plant protection products. The qualified presumption of safety (QPS) assessment was developed to provide a harmonised generic pre-assessment to support safety risk assessments performed by EFSA's scientific Panels. The safety of unambiguously defined biological agents (at the highest taxonomic unit appropriate for the purpose for which an application is intended), and the completeness of the body of knowledge are assessed. Identified safety concerns for a taxonomic unit are, where possible and reasonable in number, reflected as 'qualifications' in connection with a recommendation for a QPS status. The list of QPS recommended biological agents was reviewed and updated in the current opinion and therefore becomes the valid list. The 2016 update reviews previously assessed microorganisms including bacteria, yeasts and viruses used for plant protection purposes following an Extensive Literature Search strategy. The taxonomic units related to the new notifications received since the 2013 QPS opinion, were periodically evaluated for a QPS status and the results published as Statements of the BIOHAZ Panel. Carnobacterium divergens, Lactobacillus diolivorans, Microbacterium imperiale, Pasteuria nishizawae, Pediococcus parvulus, Bacillus flexus, Bacillus smithii, Xanthomonas campestris and Candida cylindracea were recommended for the QPS list. All taxonomic units previously recommended for the 2013 QPS list had their status reconfirmed as well their qualifications with the exception of Pasteuria nishizawae for which the qualification was removed. The exclusion of filamentous fungi and enterococci from the QPS evaluations was reconsidered but monitoring will be maintained and the status will be re-evaluated in the next QPS Opinion update. Evaluation of bacteriophages should remain as a case-by-case procedure and should not be considered for QPS status.

The Yeast Fungus Trichosporon lactis Found as an Epizoic Colonizer of Dung Beetle Exoskeletons

The study on the biology and biodiversity of coprophagous Scarabaeoidea carried out in the Polish Carpathians revealed the occurrence of unusual epizoic excrescences on various dung beetles species of the genus Onthophagus. The excrescences occur on the elytra, prothorax, and head of the studied beetles. Detailed research on this phenomenon determined that the fungus grew in the form of multicellular thalli. The ITS-based identification of fungal material collected from beetles' exoskeletons resulted in a 100 % match with Trichosporon lactis. Until now, only a yeast lifestyle/stage was known for this basidiomycete species. Therefore, in this paper, we describe a new substrate for growth of T. lactis and its unknown and intriguing relationship with dung beetles. The results obtained in this study open up numerous research possibilities on the new role of dung beetles in terrestrial ecosystems, as well as on using the physiological properties of T. lactis to restore soils.