ABIS Encyclopedia

Campylobacter fetus

Taxonomy

Morphology

Cultural characteristics

Biochemical characters

Ecology

Pathogenicity

References

Phylum Pseudomonadota (Proteobacteria), Class Epsilonproteobacteria, Order Campylobacterales, Family Campylobacteraceae,
Genus Campylobacter,
- Campylobacter fetus subsp. fetus (Smith and Taylor 1919) Veron and Chatelain 1973,
- Campylobacter fetus subsp. testudinum Fitzgerald et al. 2014,
- Campylobacter fetus subsp. venerealis (Florent 1959) Veron and Chatelain 1973.

Old synonyms: Vibrio fetus Smith and Taylor 1919, Spirillum fetus Lehmann and Neumann 1927, Vibrio fetus subsp. venerealis
Florent 1959.

Gram-negative, curved, S or seagull-shaped cells, 0.2-0.3 x 1.5-5 μm. Coccoid forms
may appear in old cultures. Very motile.

Colonies on blood agar are usually non-haemolytic, round, 1 mm in diameter,
smooth, raised, convex, and grayish white or light tan colored. Several types of
colonies may be formed. Smooth colonies, are small, 0.5 mm in diameter, round,
slightly raised, colorless, and slightly translucent. “Cut-glass” colonies are 1 mm in
diameter, round, raised, translucent, and granular with reflecting facets. Rough
colonies are rarely found. Growth on MacConkey agar is variable.
Grows on solid media containing 1.0-1.5% ox-bile and at 30 ºC, but not on media
containing 0.04% triphenyl-tetrazolium chloride. Most strains grow on media
containing 0.05% safranin and 64 mg/l cefoperazone. No growth in 2% NaCl media.

C. fetus subsp. fetus was isolated from the intestinal tracts and gallbladder of sheep, cattle, swine, birds, and humans.It has also
been isolated occasionally from the genital tract, the viscera, or the blood.
C. fetus subsp. testudinum was isolated from human blood and reptiles.
C. fetus subsp. venerealis was isolated to the bovine genital tract (semen and vaginal secretion), placenta and tissues of aborted
bovine fetuses. It is unable to survive in the intestinal tract.

C. fetus subsp. fetus is usually commensal of the intesinal tract of humans and animals. May cause sporadic abortion in cows and
sheep. Experimentally pathogenic for guinea pigs, hamsters, embryonated chicken eggs but not from rabbits, mice, or rats.
C. fetus subsp. testudinum was isolated from human blood culture.
C. fetus subsp. venerealis causes enzootic venereal sterility in cows and abortion in pregnant cows.

Don J. Brenner and J.J. Farmer III, 2001. Family I. Campylobacteraceae. In: Bergey’s Manual of Systematic Bacteriology, Second
edition,Vol 2, part C, George M. Garrity (Editor-in-Chief), pp 1145-1168.
M. Veron andR. Chatelain. Taxonomic Study of the Genus Campylobacter Sebald and Veron and Designation of the Neotype
Strain for the Type Species, Campylobacter fetus (Smith and Taylor) Sebald and Veron Int J Syst Bacteriol April 1973 23:122-134.
Fitzgerald C, Tu ZC, Patrick M, Stiles T, Lawson AJ, Santovenia M, Gilbert MJ, van Bergen M, Joyce K, Pruckler J, et al.
Campylobacter fetus subsp. testudinum subsp. nov., isolated from humans and reptiles. Int J Syst Evol Microbiol 2014; 64:2944-
2948.
Gilbert MJ, Miller WG, Leger JS, Chapman MH, Timmerman AJ, Duim B, Foster G, Wagenaar JA. Campylobacter pinnipediorum
sp. nov., isolated from pinnipeds, comprising Campylobacter pinnipediorum subsp. pinnipediorum subsp. nov. and
Campylobacter pinnipediorum subsp. caledonicus subsp. nov. Int J Syst Evol Microbiol 2017; 67:1961-1968.
Miller WG, Lopes BS, Ramjee M, Jay-Russell MT, Chapman MH, Williams TG, Wood DF, Gruntar I, Papic B, Forbes KJ.
Campylobacter devanensis sp. nov., Campylobacter porcelli sp. nov., and Campylobacter vicugnae sp. nov., three novel
Campylobacter lanienae-like species recovered from swine, small ruminants, and camelids. Int J Syst Evol Microbiol 2024; 74:
6405.

Positive results for catalase, oxidase, nitrate reduction
Negative results for urea hydrolysis, hippurate hydrolysis, H2S production onTSI and indoxyl acetate hydrolysis.

Subspecies testudinum can be distinguished phenotypically from subsp. fetus and subsp. venerealis only by MALDI-TOF MS analysis.