On-farm biosecurity measures need to be accompanied by control measures at the slaughterhouse - to reduce faecal contamination of broiler skin and to minimise cross-contamination - in order to reduce the prevalence of Campylobacter on broiler skin, according to new research from Chang Mai University in Thailand.

In the journal, Poultry Science earlier this year, C. Chokboonmongkol of that University and co-authors from the Free University in Berlin, Germany, explain that they conducted a study to determine the prevalence of Campylobacter spp. in broiler flocks by testing caecal contents at slaughter and to detect and quantify Campylobacter on broiler carcass skin samples of the corresponding slaughter batches, to determine antimicrobial resistance patterns of the Campylobacter isolates, and to genotype selected C.jejuni isolates using multi-locus sequence typing analysis.

They included 98 broiler flocks were included in the study. Intact caeca were randomly taken at the time of evisceration throughout a slaughter batch to detect Campylobacter spp. at the broiler flock level and one whole carcass per slaughter batch was taken for the detection of Campylobacter spp. on broiler skin.

The prevalence of Campylobacter spp. in broiler caeca and broiler skin samples were 11.2 per cent (11/98) and 51 per cent (50/98), respectively.

Even though most Campylobacter-positive broiler skin samples were contaminated with only up to 230 most probable number per gram, a substantial share (13.3 per cent) showed very high Campylobacter numbers on the broiler skin samples (most probable number = infinity; lower confidence limit T₀ 580 per gram).

From 32 C.jejuni and C.coli isolates tested, the highest antimicrobial resistance rates were found for ciprofloxacin (81.2 per cent), followed by tetracycline (40.6 per cent), ampicillin (31.2 per cent) and erythromycin (9.4 per cent). All tested strains were sensitive to gentamicin.

By multi-locus sequence typing analysis, a total of nine different sequence types were identified among 16 C.jejuni isolates. C.jejuni isolated from caecal content and carcass skin of the same farm or slaughter batch showed corresponding allelic profiles.

The researchers report their data suggest that intense cross-contamination during the slaughter process led to a strong increase of Campylobacter prevalence on broiler skin compared with the prevalence in broiler caeca.

Reference

Chokboonmongkol C., P. Patchanee, G. Gölz, K-H. Zessin and T. Alter. 2013. Prevalence, quantitative load, and antimicrobial resistance of Campylobacter spp. from broiler ceca and broiler skin samples in Thailand. Poult. Sci. 92(2):462-467. doi: 10.3382/ps.2012-02599

Further Reading You can view the full paper (fee payable) by clicking here.