Various species of coagulase-negative staphylococci
(C-NS) are reported to be
common in milk and on the teat skin of domestic ruminants.
The commonest C-NS
species in mastitic milk of cows varies between reports,
with Staphylococcus simulans
(Jarp, 1991) in one and Staph. hyicus in another
(Watts & Washburn, 1991). The teat
skin of heifers may be colonized by Staph. xylosus
or Staph. chromogenes, while Staph.
chromogenes and Staph. warneri are reported
as frequent isolates from teat canals and
secretion (Boddie & Nickerson, 1986; White et
al. 1989). Staph. haemolyticus was
isolated frequently from the nares, the teat skin and
the milk of goats (Valle et al.
1991), although others reported Staph. xylosus
(Bedidi-Madani et al. 1992) or Staph.
epidermidis and Staph. capitis
(Kalogridou-Vassiliadou, 1991) as the most predominant
C-NS in goats' milk. Staph. simulans has
been found experimentally to be
pathogenic for the mammary gland of meat ewes (Fthenakis
& Jones, 1990), but
little is known about the prevalence of this species in
ewes' milk collected from cases
of naturally occurring subclinical mastitis (SCM). The aim
of the present
investigation was the identification of the commonest
C-NS species in ewes' milk
collected from field cases of SCM or predominating in the
ewes' environment.