Identification of campylobacters from bovine and ovine faeces

Campylobacters isolated in Scotland and the north of England from bovine (497 isolates) and ovine (51 isolates) faeces were studied in order to determine which simple methods would be useful for identification of groups and species. By means of the catalase test, growth and microscopic characteristics, coccal transformation and nalidixic acid (Nal) and cephalothin sensitivity, isolates were separated into 3 groups: C. jejuni - C. coli, C. hyointestinalis - C. fetus and C. fecalis - C. sputorum subsp. bubulus. Hippurate hydrolisis was used to differentiate C. jejuni (positive) from all the other Campylobacter spp (negative). The production of hydrogen sulphide in Triple Sugar Iron was used to separate C. hyointestinalis and the C. fecalis - C. sputorum subsp. bubulus group (positive) from C. fetus (negative). The production of hydrogen sulphide in iron-bisulphite-pyruvate (FBP) medium was used to separate the C. fecalis - C. sputorum subsp. bubulus group (positive) from most C. hyointestinalis isolates (96.4% were negative). Additional characteristics useful for identification of the C. fecalis - C. sputorum subsp. bubulus group were: adherent sticky growth; inhibition of growth by FBP or ferrous sulphate and sodium metabisulphite; and inversion of Nal resistance on FBP agar. Catalase test was used to separate C. fecalis (positive) from C. sputorum subsp. bubulus (negative), although these two species should be regarded as a single species with a variable catalase test. Bovine C. hyointestinalis isolates were serologically classified as type 1 (related to the porcine C. hyointestinalis standard strain NCTC 11562) and type 2 (unrelated). Based on the above criteria, isolates in cattle were classified as: 229 C. jejuni, 66 C. coli, 112 C. hyointestinalis type 1, 53 C. hyointestinalis type 2 and 37 C. fetus. In sheep they were: 25 C. jejuni, 11 C. coli, 12 C. fecalis and 3 C. sputorum subsp. bubulus.