Pathogenicity and Antibiotic Resistance Diversity in Clostridium perfringens Isolates from Poultry Affected by Necrotic Enteritis in Canada

Abstract

Necrotic enteritis (NE) caused by C. perfringens is one of the most common diseases of poultry and results in a huge economic loss to the poultry industry, with resistant clostridial strains being a serious concern and making the treatment difficult. Whole-genome sequencing approaches represent a good tool to determine resistance profiles and also shed light for a better understanding of the pathogen. The aim of this study was to characterize, at the genomic level, a collection of 20 C. perfringens isolates from poultry affected by NE, giving special emphasis to resistance mechanisms and production of bacteriocins. Antimicrobial resistance genes were found, with the tet genes (associated with tetracycline resistance) being the most prevalent. Interestingly, two isolates carried the erm(T) gene associated with erythromycin resistance, which has only been reported in other Gram-positive bacteria. Twelve of the isolates were toxinotyped as type A and seven as type G. Other virulence factors encoding hyaluronases and sialidases were frequently detected, as well as different plasmids. Sequence types (ST) revealed a high variability of the isolates, finding new allelic combinations. Among the isolates, C. perfringens MLG7307 showed unique characteristics; it presented a toxin combination that made it impossible to toxinotype, and, despite being identified as C. perfringens, it lacked the housekeeping gene colA. Genes encoding bacteriocin BCN5 were found in five isolates even though no antimicrobial activity could be detected in those isolates. The bcn5 gene of three of our isolates was similar to one previously reported, showing two polymorphisms. Concluding, this study provides insights into the genomic characteristics of C. perfringens and a better understanding of this avian pathogen.

Prevalence and Antibiotic Resistance Profile of Clostridium perfringens Isolated from Pork and Chicken Meat in Vietnam

“…The lowest resistance rates to tetracycline and clindamycin were also observed in a study conducted in Canada. C. perfringes isolated from poultry in that study were 50% and 40% resistant to tetracycline and clindamycin, respectively [42]. Our study also revealed that the resistance rate of C. perfringens to cefoxitin (4.35%) and imipenem (8.7%) was still low.…”

“…To date, studies on the occurrence and antimicrobial resistance of C. perfrigens isolates have mainly focused on humans and food-producing animals [42][43][44][45]. There are only a few publications on C. perfringens of food origin [46,47].…”

Antimicrobial Activity of Synthetic Enterocins A, B, P, SEK4, and L50, Alone and in Combinations, against Clostridium perfringens

“…Whole genome sequencing of the C. perfringens collection was performed previously [3] using the Illumina technique at the Hospital Center of University Laval (CHUL), Quebec, Canada. Some of the sequences were further analyzed in this study.…”

“…Pairwise alignments and visualization of the products of the genes encoding the Man-PTS subunit IID (manZ_1, manZ_2, and manZ_3) from the selected isolates were performed with the program Jalview 2.11.2.5 [47] in order to detect mutations and explain differences in enterocin susceptibility between strains. The isolates C. perfringens MLG 0418, 2919, and 7307 (which previously showed unique characteristics [3]) were chosen for analysis of the Man-PTS receptor. Sequences from C. perfringens ATCC 13124 were added as a reference.…”

“…In countries where antibiotic growth promoters are no longer used, infections such as poultry-associated necrotic enteritis (NE) induced by Clostridium perfringens have increased. Some of these Clostridium strains are multidrug-resistant [3], which suggests that this may also be the case for other relevant pathogens [4]. Necrotic enteritis caused by C. perfringens is one of the most common poultry diseases and causes huge economic losses in poultry farming [5].…”