Investigation of Clostridium perfringens in small-scale commercial broiler flocks in Mymensingh district of Bangladesh

Abstract

Background and aim: Necrotic enteritis (NE) is one of the most prevalent diseases in broiler poultry caused by Clostridium perfringens connected with significant economic losses. A cross-sectional survey was conducted in Mymensingh district of Bangladesh to assess the prevalence of C. perfringens through toxinotyping molecular assay and confirm the risk factors for NE, including antimicrobial-resistant (AMR) status of the isolates.

Materials and methods: We included 40 small-scale commercial broiler farms randomly selected from two subdistricts of Mymensingh district of Bangladesh. As an individual sample, 240 cloacal swabs, and as a pooled sample, 40 drinking water, 40 workers' hand washing, 40 litter swab, and 40 feed samples were collected and evaluated by culture, biochemical, and molecular assays. A pretested semi-structured interview questionnaire was employed to capture flock-level data on risk factors from the farm owners. The flock-level data on risk factors were assessed through univariable and multivariable logistic regression analyses with p<0.05 was considered statistically significant.

Results: Overall flock-level prevalence of C. perfringens was estimated to be 10.3% (95% confidence interval [CI] 7.5-13.6%). Litter swab (pooled) was found to be highly contaminated with C. perfringens (25.0%, 95% CI: 12.7-41.2%) followed by the cloacal swab (10.4%, 95% CI: 6.9-15.0%) and feed sample (5.0%, 95% CI: 0.6-16.9%). History of coccidia infection (Adjusted odds ratio =33.01, 95% CI: 2.14-507.59, p=0.01) was significantly associated with flock-level C. perfringens infection status. In this study, 78.1% isolates were found as multidrug-resistant as they demonstrated resistance to 3-5 antimicrobial agents.

Conclusion: Evidence-based control options need to be taken through the uses of prebiotics and probiotics, biosecurity, and hygienic measurement, including control of coccidia infection, is needed to lessen the NE infection and AMR related to this pathogen in small-scale commercial broiler poultry.

Keywords: Bangladesh; Clostridium perfringens; antimicrobial-resistant; broiler; necrotic enteritis; prevalence.

Figure-1

Locations of the surveyed farms in two subdistricts (Mymensingh Sadar and Trishal) of Mymensingh district of Bangladesh indicated by arrows on the map. The map was produced in ArcGIS-ArcMap version 10.3 (ESRI Co., Redlands, California, USA) using geographic coordinates of the study locations captured via Garmin eTrex 10. A total of 40 broiler farms were surveyed that represented equal number of farms were included from each subdistrict with a flock size >3000 birds under sector three production systems [Source: Map was prepared using ArcGIS-ArcMap software version 10.3].

Figure-2

Agarose gel electrophoresis showing 402 bp amplicon of alpha-toxin gene (cpa gene) of Clostridium perfringens [14]. Lane M: 100 bp DNA marker; lane N: Negative control; lanes 1-4: Isolates positive for C. perfringens.

Figure-3

Distribution of antimicrobial resistance status for Clostridium perfringens (n=41) strains isolated from broiler farms, R=Number of antibiotic resistances; AMX=Amoxicillin, CHL=Chloramphenicol, ERY=Erythromycin, OTE=Oxytetracycline, GEN=Gentamicin, n=Number of isolates with the indicated pattern.