CAMPYLOBACTER AGAR BASE

Campylobacter species are ubiquitous in the environment inhabiting a wide variety of ecological niches. Infection with a Campylobacter species is one of the most common causes of human bacterial gastroenteritis. Most species are found in animals (cattle, swine) and cause infertility and abortion. C. jejuni was originally isolated on a blood-containing media with antibiotics. Skirrow described a selective medium for Campylobacter species consisting of Blood Agar Base No. 2 supplemented with horse blood and antibiotics. Subsequently, Blaser et al isolated C.jejuni on Brucella Agar supplemented with sheep blood and four antibiotics. Later on, a fifth antibiotic, cephalothin was added to improve the selectivity of the medium by inhibition of accompanying faecal bacteria. Campylobacter Agar Base is recommended by APHA for selective isolation of Campylobacter species.
Campylobacter Agar Base is well supplemented to support luxuriant growth of Campylobacter species. Osmotic equilibrium of the medium is maintained by sodium chloride. Blood serves as an additional source of nutrients including X-factor. The antibiotic supplements namely Blaser-Wang and Skirrow markedly reduce the growth of normal enteric bacteria while enhancing the growth and recovery of C.jejuni from faecal specimens. Amphotericin B in Blaser- Wang supplement greatly or completely inhibits growth of fungi. C.jejuni colonies appear non-haemolytic, flat and gray with an irregular edge or raised and round with a mucoid appearance. Some strains may appear tan or slightly pink. Swarming may be observed on moist surfaces. Incubation at 35-37?C may show a delayed growth of C.jejuni cultures. Incubating the plates at 42?C can fasten this.
The contaminated food sample (10 to 25 grams) is enriched in Campylobacter Enrichment Broth Base. The broth is incubated with agitation under a micro aerobic atmosphere for 16-18 hrs. The enrichment culture is then plated onto the selective media i.e. Campylobacter Agar Base.

for selective isolation of Campylobacter species from faecal, food and environmental samples