RESUMO
Multilocus sequence typing (MLST) was used to study the genetic diversity and population structure of 48 Candida albicans (C. albicans) isolates from the udder or genital tract of apparently healthy or diseased camels. This study aimed also to determine the frequency of C. albicans isolates in the genital tract and udder of healthy or diseased female dromedary camels. A total of 240 mature dromedary camels (230 females and 10 males) were categorized based on the clinical examination of gentile tract and udder into five groups [fertile females (n = 70), infertile females (n = 115), healthy udder (n = 15), mastitis (n = 30), and fertile males (n = 10)]. Swabs were collected from male and female genital tracts of dromedary camels and milk samples were collected from healthy and diseased udders. C. albicans was isolated from 20% of the samples. The frequency of isolation was significantly higher (p < 0.00001) in disease camels (75%) compared with apparently healthy camels (25%). Most of C. albicans was isolated from infertile female genitalia (62.50%) which was significantly higher than that isolated from fertile female genitalia (16.67%). Multilocus sequence (MLS) analysis identified seven different diploid sequence types (DSTs) including DST2, DST50, DST62, DST69, DST124, DST142, and DST144. The most frequently identified DTS was DST69 (13/48) which significantly higher (p ≤ 0.05) than DST2, DST62, and DST124. The frequency of identification of DST50, DST142, and DST 144 was significantly higher (p ≤ 0.05) than DST62. DST62 and DST124 were isolated only from diseased camels. DST62 was isolated only from mastitic milk. DST124 was isolated only from infertile female genitalia. The percentage of DST50 and DST 142 was significantly higher in diseased camels (infertile females) than in the apparently healthy ones (fertile females). DST2 and DST50 were isolated only from female genitalia of apparent health and diseased camels. The C. albicans isolated from diseased camels had significantly higher biofilm formation, hydrophobicity, phospholipase, proteinase, and hemolysin activities compared with the isolates from apparent healthy camels. All isolates were sensitive to amphotericin B, itraconazole, micafungin, posaconazole and voriconazole. In conclusion, the present study represents the first molecular typing of C. albicans in samples isolated from milk and the genital tract of the dromedary camel. MLST is a useful tool for studying the epidemiology and evolution of C. albicans. Early identification of Candida species and attention to Candida virulence factors and their antifungal susceptibility patterns is very important for establishing strategies to control and/or prevent candidiasis by novel therapeutic management. Amphotericin B, itraconazole, micafungin, posaconazole, or voriconazole can be efficient in treatment of candidiasis.
RESUMO
AIM: The present study was designed for the detection of the most prevalent respiratory infections in chicken flocks and clarifying their interaction and impact on flock health. MATERIALS AND METHODS: A total of 359 serum samples were collected from 55 backyard chickens and tested using commercial enzyme-linked immunosorbent assay kits to determine the seroprevalence of Newcastle disease virus (NDV), infectious bronchitis virus (IBV), influenza type A, Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS). Molecular prevalence of NDV, IBV, low pathogenic avian influenza virus (LPAIV) H9N2, MG, and MS was carried out on swab, and tissue samples collected from 55 backyard flocks and 11 commercial broiler flocks suffered from respiratory infections using polymerase chain reaction (PCR) and reverse transcription-PCR. RESULTS: Seroprevalence of NDV, IBV, Influenza type A virus, MG, and MS in chicken backyard flocks was 56.4%, 50.9%, 12.7%, 14.5%, and 3.6%, respectively. Specific antibodies against one or more respiratory viruses and mycoplasma were detected in 36.4% of backyard flocks, indicating concurrent viral infections. The molecular survey showed that 90.9% of chicken backyard flocks were infected with common respiratory viruses (NDV, IBV, and LPAIV H9N2) while 81.8% of commercial broiler flocks were infected. The molecular prevalence rate of NDV, IBV, and LPAIV H9N2 was 46.97%, 56.1%, and 19.7% in backyard flocks, respectively. Combined viral and bacterial infection represented 40% and 63.6% of the respiratory infections, resulting in enhanced pathogenicity and increased mortalities of up to 87.5% and 27.8% in backyard and commercial flocks, respectively. Mixed infection of IBV, LPAIV H9N2, and/or Escherichia coli is the most prevalent mixed infection in broiler flocks, inducing severe clinical outcomes. Avian pathogenic E. coli was, respectively, isolated from 40% of backyard flocks and 81.82% of broiler flocks. Staphylococcus aureus was isolated from three backyard chicken flocks mixed with other respiratory pathogens with elevated mortality. Mixed infection of E. coli and MG reported in 9.1% of broiler flock. MG was detected in 14.5% of backyard flocks and 9.1% of broiler flocks while MS was detected only in 3.6% of backyard chickens mixed with E. coli, and other viruses. CONCLUSION: Our results confirm that mixed infections are more commonly prevalent and associated with dramatic exacerbation in clinical outcomes than a single infection. Bidirectional synergistic interaction between these concurrently interacted respiratory pathogens explains the severe clinical impact and high mortality rate. The high prevalence of IBV (either as a single or combined infection) with LPAIV H9N2 and/or E. coli, in spite of intensive use of commercial vaccines, increases the need for revising vaccination programs and the application of standard biosecurity measures. Backyard chickens impose a great risk and threaten commercial flocks due to the high prevalence of viral respiratory pathogens.
