Campylobacter jejuni inactivation in New Zealand soils

• Published in: Journal of applied microbiology Vol. 101; no. 5; pp. 1188 - 1197
• Main Authors: Ross, C.M., Donnison, A.M.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.11.2006; Blackwell Science
• Subjects: Biological and medical sciences; Campylobacter jejuni; Campylobacter jejuni - growth & development; Campylobacter jejuni - isolation & purification; farm dairy effluent; Fundamental and applied biological sciences. Psychology; Microbiology; New Zealand; pathogen; Rain; Soil - analysis; Soil Microbiology; soils; Temperature; Time Factors; New Zealand; Oceania; New Zealand; Soils; Campylobacterjejuni; Applied microbiology; farm dairy effluent; Campylobacteraceae; Pathogenic; Bacteria; pathogen; Inactivation; Effluent; Campylobacter jejuni
• ISSN: 1364-5072; 1365-2672
• DOI: 10.1111/j.1365-2672.2006.02984.x

Aim:  The study was undertaken to determine the inactivation rate of Campylobacter jejuni in New Zealand soils. Methods and Results:  Farm dairy effluent (FDE) inoculated at c. 105 ml−1 with C. jejuni was applied to intact soil cores at a rate of 2 l m−2. Four soils were used: Hamilton (granular); Taupo (pumice); Horotiu and Waihou (allophanic). After FDE application cores were incubated at 10°C for up to 32 days. For all four soils all the FDE remained within the cores and at least 99% of C. jejuni were retained in the top 5 cm. Campylobacter jejuni had declined to the limit of detection (two C. jejuni 100 g−1) by 25 days in Hamilton and Taupo soils and by 32 days in Waihou soil. In contrast, in Horotiu soil the decline was only three orders of magnitude after 32 days. Simulated heavy rainfall was applied 4 and 11 days after FDE application and only about 1% of the applied C. jejuni were recovered in leachates. Conclusions:  This study demonstrated that at least 99% of applied C. jejuni were retained in the top 5 cm of four soils where they survived for at least 25 days at 10°C. Significance and Impact of the Study:  Soil retention of C. jejuni is efficient at FDE application rates that prevent drainage losses. The low infectious dose of C. jejuni and its ability to survive up to 25 days have implications for stock management on dairy farms.