1. A new selective medium (CFC) has been developed for the rapid isolation of pigmented and non-pigmented pseudomonads associated with the spoilage of poultry meat held under chill conditions. It comprises Difco Heart Infusion Agar supplemented with 50 microgram cephaloridine, 10 microgram fucidin and 10 microgram cetrimide/ml. 2. CFC medium was found to be more selective than three other media which have been used for isolating pseudomonads from foods, when tested with pure cultures of 28 reference organisms. 3. CFC supported the growth of a higher proportion of pseudomonads from freshly-eviscerated carcasses and processing equipment when the organisms were present only in low numbers relative to other genera.

1. Changes in the caecal flora of chicks aged from approximately 3 h to 14 d were studied. 2. Counts obtained by means of a conventional anaerobic plating method and a method for the stricter anaerobes remained comparable throughout but occasionally it was found that strains of anaerobic bacteria isolated from the predominant flora of 4- to 14-d-old birds could not be grown when tested by the conventional method. 3. During the 14-d period approximately 100% of the organisms isolated on anaerobic plates utilised uric acid up to the third day but the incidence subsequently declined and in one case represented only 4% of the total flora. 4. The predominant uric acid-utilising bacteria were Streptococcus faecalis and Escherichia coli up to 3 d of age and various types of anaerobic bacteria thereafter. 5. None of the isolates showed an absolute requirement for uric acid.

The incidence of Staphylococcus aureus on turkeys sampled at various stages of processing and further-processing was determined on four occasions at each of three different processing plants. For freshly-slaughtered birds, counts from neck skin varied from plant to plant over the range less than 10(2) to greater than 10(5)/g but in all cases the corresponding counts obtained from carcasses sampled after chilling rarely exceeded 10(3)/g and the same was true for samples of mechanically recovered meat (MRM), the final raw product examined. Despite the limited susceptibility of isolates from the different factories to typing by means of either standard human or poultry bacteriophages (55-94% untypable), evidence was obtained with the aid of biotyping for the presence of both human and animal-derived strains. However, some biotypes isolated from MRM were not detected at earlier stages of processing. At one processing plant, an "indigenous' type of S. aureus was clearly demonstrated. It occurred in high numbers in the defeathering machines (up to 10(5)/swab), was found on carcasses at all subsequent stages of processing over the survey period and was shown to survive routine cleaning and disinfection procedures. Isolates of this type produced unusually large amounts of extracellular "slime' in artificial culture. Two of the three processing plants yielded isolates which were enterotoxigenic. Of 55 strains from Plant 1, 60% produced enterotoxin C and all were of the "indigenous' type. In the case of Plant 2, only two type D- and one type F-producing strain were found.

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