Affiliation:
1. Poultry Diagnostic and Research Center
2. Athens Diagnostic Laboratory
3. Department of Population Health
4. Center for Food Safety, College of Agriculture and Environmental Sciences, University of Georgia, Griffin, Georgia 30223
5. Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602
Abstract
ABSTRACT
While characterizing the intestinal bacterial community of broiler chickens, we detected ε-proteobacterial DNA in the ilea of 3-day-old commercial broiler chicks (J. Lu, U. Idris, B. Harmon, C. Hofacre, J. J. Maurer, and M. D. Lee, Appl. Environ. Microbiol.
69:
6816-6824, 2003). The sequences exhibited high levels of similarity to
Campylobacter jejuni
and
Campylobacter coli
sequences, suggesting that chickens can carry
Campylobacter
at a very young age.
Campylobacter
sp. was detected by PCR in all samples collected from the ilea of chicks that were 3 to 49 days old; however, it was detected only in the cecal contents of chickens that were at least 21 days old. In order to determine whether the presence of
Campylobacter
DNA in young chicks was due to ingestion of the bacteria in food or water, we obtained commercial broiler hatching eggs, which were incubated in a research facility until the chicks hatched. DNA sequencing of the amplicons resulting from
Campylobacter
-specific 16S PCR performed with the ileal, cecal, and yolk contents of the day-of-hatching chicks revealed that
Campylobacter
DNA was present before the chicks consumed food or water. The 16S rRNA sequences exhibited 99% similarity to
C. jejuni
and
C. coli
sequences and 95 to 98% similarity to sequences of other thermophilic
Campylobacter
species, such as
C. lari
and
C. upsaliensis
. The presence of
C. coli
DNA was detected by specific PCR in the samples from chicks obtained from a commercial hatchery; however, no
Campylobacter
was detected by culturing. In order to determine whether the same strains of bacteria were present in multiple levels of the integrator, we cultured
Campylobacter
sp. from a flock of broiler breeders and their 6-week-old progeny that resided on a commercial broiler farm. The broiler breeders had been given fluoroquinolone antibiotics, and we sought to determine whether the same fluoroquinolone-resistant strain was present in their progeny. The isolates were typed by pulsed-field gel electrophoresis, which confirmed that the parental and progeny flocks contained the same strain of fluoroquinolone-resistant
C. coli
. These data indicate that resistant
C. coli
can be present in multiple levels of an integrated poultry system and demonstrated that molecular techniques or more sensitive culture methods may be necessary to detect early colonization by
Campylobacter
in broiler chicks.
Publisher
American Society for Microbiology
Subject
Ecology,Applied Microbiology and Biotechnology,Food Science,Biotechnology