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. 1989 Dec;103(3):465–474. doi: 10.1017/s0950268800030879

The effect of pre-enrichment on recovery of Streptococcus agalactiae, Staphylococcus aureus and mycoplasma from bovine milk.

M C Thurmond 1, J W Tyler 1, D M Luiz 1, C A Holmberg 1, J P Picanso 1
PMCID: PMC2249543  PMID: 2691266

Abstract

The study was conducted to determine whether pre-enrichment would increase sensitivity of detecting Streptococcus (Str.) agalactiae, Staphylococcus (S.) aureus, and mycoplasma in bovine milk. Two procedures were followed, one involving direct inoculation of milk on bovine blood agar, and the other involving preenrichment in broth followed by inoculation on agar. Logistic regression was used to predict the probability of isolation as a function of culture procedure and two additional covariates, the California Mastitis Test (CMT) score of the milk and the type of sample (indicating sample storage temperature and herd mastitis status). A total of 13778 milk samples was cultured for each of the three bacteria. By using results of both direct inoculation and pre-enrichment, the probability of isolation compared to use of direct inoculation only and adjusted for effects of other variables was increased 3.6-fold for Str. agalactiae, 1.6-fold for S. aureus and 1.7-fold for mycoplasma. The probability of isolation for all three bacteria increased as the CMT score increased. For Str. agalactiae, there was a statistical interaction predicting that enrichment improved the odds of isolation more from milk with high CMT scores than from milk with low scores. Results indicate that pre-enrichment can substantially increase the sensitivity of bacteriological screening of dairy cows for mastitis caused by Str. agalactiae, S. aureus, and mycoplasma.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Bennett R. H., Jasper D. E. Immunosuppression of humoral and cell-mediated responses in calves associated wtih inoculation of Mycoplasma bovis. Am J Vet Res. 1977 Nov;38(11):1731–1738. [PubMed] [Google Scholar]
  2. Blowey R. W. Mastitis monitoring in general practice. Vet Rec. 1984 Mar 17;114(11):259–261. doi: 10.1136/vr.114.11.259. [DOI] [PubMed] [Google Scholar]
  3. Bushnell R. B. Herd health approach to mastitis control and milk quality. J Am Vet Med Assoc. 1980 Apr 15;176(8):746–750. [PubMed] [Google Scholar]
  4. Bushnell R. B. The importance of hygienic procedures in controlling mastitis. Vet Clin North Am Large Anim Pract. 1984 Jul;6(2):361–370. doi: 10.1016/s0196-9846(17)30029-0. [DOI] [PubMed] [Google Scholar]
  5. Jasper D. E. Bovine mycoplasmal mastitis. Adv Vet Sci Comp Med. 1981;25:121–157. [PubMed] [Google Scholar]
  6. Jasper D. E., Dellinger J. D., Rollins M. H., Hakanson H. D. Prevalence of mycoplasmal bovine mastitis in California. Am J Vet Res. 1979 Jul;40(7):1043–1047. [PubMed] [Google Scholar]
  7. Jasper D. E., Jain N. C., Brazil L. H. Clinical and laboratory observations on bovine mastitis due to Mycoplasma. J Am Vet Med Assoc. 1966 May 1;148(9):1017–1029. [PubMed] [Google Scholar]
  8. Neave F. K., Dodd F. H., Kingwill R. G., Westgarth D. R. Control of mastitis in the dairy herd by hygiene and management. J Dairy Sci. 1969 May;52(5):696–707. doi: 10.3168/jds.S0022-0302(69)86632-4. [DOI] [PubMed] [Google Scholar]
  9. Raccach M., Rottem S., Razin S. Survival of frozen mycoplasmas. Appl Microbiol. 1975 Aug;30(2):167–171. doi: 10.1128/am.30.2.167-171.1975. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. SCHALM O. W., NOORLANDER D. O. Experiments and observations leading to development of the California mastitis test. J Am Vet Med Assoc. 1957 Mar 1;130(5):199–204. [PubMed] [Google Scholar]
  11. Thurmond M. C., Holmberg C. A., Luiz D. M. Evaluation of a digitonin disk assay to discriminate between acholeplasma and mycoplasma isolates from bovine milk. Cornell Vet. 1989 Jan;79(1):71–81. [PubMed] [Google Scholar]

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