Chlamydophila pecorum: Introduction / history
Introduction
Chlamydial strains previously designated Chlamydia pecorum
(Fukushi and Hirai, 1992),
have been reclassified as Chlamydophila pecorum (Everett et al.,
1999).
All of this chlamydial species are associated with infections in mammals
including: cattle sheep and goats (Fukushi and Hirai,
1992); koala (Girjes et al., 1993) and
swine (Kaltenboeck and
Storz, 1992; Anderson et al.,
1996).
Pathogenically diverse, C. pecorum strains are associated with pneumonia, polyarthritis, conjunctivitis, abortion, encephalomyelitis, enteritis and diarrhoea
(Kaltenboeck et al., 1993).
They may also cause metritis, salpingitis and infertility in cattle. In koalas, infection with C. pecorum
causes genito-urinary disease [see Koala].
History
The chlamydial isolates now designated as C. pecorum
were distinct from other C. psittaci with which they were formerly classified
by the diseases produced. Biotyping (Spears and
Storz, 1979) and immunotyping (Perez-Martinez and
Storz, 1985)
all distinguished the present C. pecorum from the organisms of chlamydial abortion
in ruminants that have themselves been reclassified as C. abortus [see C.
abortus in ruminants]. Among C. pecorum strains: biotype 2 / immunotype 2
is associated with polyarthritis, conjunctivitis or encephalomyelitis in cattle and sheep; biotype 3 / immunotype 3
causes intestinal infection in cattle; biotype 4 / immunotype 4 causes polyarthritis in pigs; biotype 4 / immunotype 6
causes pneumonia or abortion in pigs; immunotype 9 causes intestinal infection in sheep.
Strains of the former Biotype 1 / immunotype 1 causing abortion in sheep and cattle are now designated Chlamydophila abortus;
Biotype 7 / immunotype 7 strains causing conjunctivitis, rhinitis and pneumonitis in cats are now
designated Chlamydophila felis.
Early reports described the recovery of chlamydial organisms from the faeces of clinically healthy animals, including cattle
(Wilson, 1963) sheep (Storz,
1964) and goats (Omori et al.,
1957). Some of these isolates produced pneumonia and abortion after experimental challenge (Storz,
1964). In general, C. pecorum strains were non-invasive in a mouse model of virulence
compared to C. abortus strains from sheep (Rodolakis et al.,
1989).
NEXT: C.
pecorum: Epidemiology
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