ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00062.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00063.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

SUMMARY:Three strains of aerobic spore forming bacteria have been studied in association with thermoduric streptococci in pasteurized milk at different temperatures. Generally the development of each component organism of the mixtures was unaffected in the initial stages by the presence of the other, though later the spore formers were frequently adversely affected. Acid production by the mixed cultures was compared with that of the pure cultures under the same conditions of incubation. Generally more acid was formed by the mixtures, particularly at the higher temperatures of incubation. Gas formation was noted by a culture ofStreptococcus faecalisin association with the spore formers.

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00064.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

SUMMARY:Two methods have been developed for isolating and enumerating group D faecal streptococci from localities such as bacon factories where they are heavily outnumbered by other organisms. The first depends on presumptive counts in a Lab‐Lemco‐peptone‐glucose broth (pH 6·0) containing 0·1% of thallous acetate with confirmation by streaking on tetrazolium agar. The other method involves direct plating on tetrazolium‐glucose agar (pH 6·0) containing 0·1% of thallous acetate. On the tetrazolium medium differentiation can be made betweenStreptococcus faecalisand its variantszymogenesandliquefaciensand the other group D organisms,Strep. faecium, Strep. duransandS

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00065.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

SUMMARY:A survey has been made of the numbers and types of group D faecal streptococci in three bacon factories. AlthoughStreptococcus faecium, normally present in the gut of the pig and isolated from spoiled canned hams, was found, it was often outnumbered byStrep. faecalis, an indicator of human faecal contamination which is rare in the pig. The rôle of these two organisms in ham spoilage is discussed. The value of thallous acetate‐tetrazolium‐glucose agar for isolating and distinguishing these organisms has been demonstrated, and it is suggested that the method may have more general application where it is necessary to differentiate between faecal streptococci of human and animal or

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00066.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00067.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

SUMMARY:Colony counts at 30° were greater than 10 times those at 37° in a high proportion of rinses of washed milk cans, the difference being most marked in those containing milk scale, where 58% of the colony counts at 30° exceeded 106/can. A high proportion of the microflora was composed of thermoduric bacteria. Of 895 cultures from the milk scale, 33% were micrococci, 28% corynebacteria, 22% streptococci, and 9% were Gram‐negative rods. Though aerobic sporing rods constituted only 5% of the microflora of the milk scale, they were present in large numbers and unsatisfactorily washed cans probably constitute one of the main sources of these organisms in

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00068.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

SUMMARY:Alterations in peptone concentration, pH and time of autoclaving of peptone water resulted in considerable variation in extinction time estimates. The longest extinction times were obtained with the higher peptone concentration, pH 7·0 and the shorter period of autoclaving

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00069.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

SUMMARY:Viable counts were made in three media of material from the crop, gizzard, duodenum, ileum and caeca of chicks. Groups of birds 2, 4, 7, 10, 13, 16 and 30 days old were studied. The results showed that a balanced gut flora is established one day after feeding. An indication of the actual development of the flora was obtained in chicks 4 hr after feeding. The relationship between the flora at different ages and that in newly‐hatched chicks before feeding is discusse

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00070.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

SUMMARY:Pectolytic bacteria in considerable numbers were detected in samples from farm water supplies. Two media were employed, and quantitative data were obtained, in both cases, but colony counts on sodium pectate‐calcium agar poured plates gave higher numbers than a presumptive count in sodium pectate solution. The agar medium also permitted the growth of non‐pectolytic bacteria, and the total colony count was higher than that obtained on standard nutrient agar. Presumptive coliaerogenes counts in broth tubes showed that these organisms were, on the average, about four times as numerous as the pectolytic organi

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1956.tb00071.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY