Identification of a Brevibacterium marker gene specific to poultry litter and development of a quantitative PCR assay.
OBJECTIVE
To identify a DNA sequence specific to a bacterium found in poultry litter that was indicative of faecal contamination by poultry sources.


RESULTS
Faecally contaminated poultry litter and soils were used as source material for the development of a quantitative polymerase chain reaction (qPCR) method targeting the 16S rRNA gene of a Brevibacterium sp. The identified sequence had 98% nucleotide identity to the 16S rRNA gene of Brevibacterium avium. The qPCR method was tested on 17 soiled litter samples; 40 chicken faecal samples; and 116 nontarget faecal samples from cattle, swine, ducks, geese, and human sewage collected across the United States. The 571-bp product was detected in 76% of poultry-associated samples, but not in 93% of faecal samples from other sources. Marker concentrations were 10(7) -10(9) gene copies per gram in soiled litter, up to 10(5) gene copies per gram in spread-site soils, and 10(7) gene copies per litre in field run-off water. Results were corroborated by a blinded study conducted by a second laboratory.


CONCLUSIONS
The poultry-specific PCR product is a useful marker gene for assessing the impact of faecal contamination as a result of land-applied poultry litter.


CONCLUSIONS
This study describes the first quantitative, sensitive and specific microbial source tracking method for the detection of poultry litter contamination.
Weidhaas
J L
JL
North Wind, Inc., Idaho Falls, ID, USA.
Macbeth
T W
TW
Olsen
R L
RL
Sadowsky
M J
MJ
Norat
D
D
Harwood
V J
VJ
D000818:Animals; D001951:Brevibacterium / Q000145:classification / Q000235:genetics*; D002417:Cattle / Q000382:microbiology; D002645:Chickens / Q000382:microbiology*; D015169:Colony Count, Microbial; D004269:DNA, Bacterial / Q000235:genetics; D004784:Environmental Monitoring / Q000379:methods; D005243:Feces / Q000382:microbiology*; D005798:Genes, Bacterial; D006801:Humans; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D012150:Polymorphism, Restriction Fragment Length; D011200:Poultry / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012722:Sewage / Q000382:microbiology; D012987:Soil / Q000032:analysis; D012988:Soil Microbiology; D013552:Swine / Q000382:microbiology; D014481:United States
D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D012722:Sewage; D012987:Soil