Increased milk levels of insulin-like growth factor 1 (IGF-1) for the identification of bovine somatotropin (bST) treated cows†

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Andreas Daxenberger, Helga Sauerwein and Bernhard H. Breier


Abstract

The present EU moratorium banning the use of bST to increase milk yield implies the need for official controls. Our study aimed to identify milk from bST treated cows via the induced increase of insulin-like growth factor 1 (IGF-1) concentrations. A non-extraction radioimmunoassay for IGF-1 was improved and thoroughly validated for milk. Accuracy was 99% recovery in a fortified sample material, the precision was 5.1% intra-assay variation and 13.4% inter-assay variation. Parallelism was proved by a dilution experiment which yielded a regression line with a slope (–0.7%) not significantly different from zero (P = 0.534). Naturally occurring milk IGF-1 levels were recorded in 5777 random milk samples from the Bavarian dairy cow population. In samples from lactation week 7 to 33, the effect of somatic cell count (SCC), protein content and parity could be quantified and corrected; thus a normal distribution (–0.068 mean ± 0.440 s) of the corrected logarithmic IGF-1 levels (corr ln IGF-1) was obtained. IGF-1 concentrations occurring in milk from bST treated cows were recorded in 33 Brown Swiss cows treated once with rbST (POSILAC®). Mean corr ln IGF-1 levels increased by 0.828 and 0.477 in first parity and older cows, respectively. Thus 60% and 29%, respectively, of the positives could be detected at a 95% probability. If our results are confirmed in experiments with more bST treated cows and with prolonged treatment intervals, IGF-1 measurements might be useful to monitor for bST application in milk samples.


References

  1. Council Decision, 94/936, 1994, No L 366/19.
  2. T. J. Centner and K. W. Lathrop, J. Dairy Sci., 1997, 80, 215 Search PubMed.
  3. D. E. Bauman, J. Dairy Sci., 1992, 75, 3432 Search PubMed.
  4. D. E. Bauman and R. G. Vernon, Ann. Rev. Nutr., 1993, 13, 437 CrossRef CAS.
  5. D. Schams, F. Graf, J. Meyer, B. Graule, M. Mauthner and C. Wollny, J. Anim. Sci., 1991, 69, 1583 Search PubMed.
  6. O. L. Hadsell, C. R. Baumrucker and R. S. Kensinger, J. Endocrinol., 1993, 137, 223 Search PubMed.
  7. B. K. Sharma, M. J. Vandehaar and N. K. Ames, J. Dairy Sci., 1994, 77, 2232 Search PubMed.
  8. X. Zhao, B. W. McBridge, L. M. Trouten-Radford, L. Golfman and J. H. Burton, Dom. Anim. Endocr., 1994, 11(2), 209 Search PubMed.
  9. D. Schams, in Use of Somatotropin in Livestock Production, ed. K. Sejersen, M. Vesterhaard and A. Neiman-Sorensen, Elsevier, London, 1989, p. 192 Search PubMed.
  10. A. R. Torkelson, K. A. Dwyer, G. J. Rogan and R. L. Ryan, J. Dairy Sci., 1987, 70(Suppl 1), 146 Search PubMed.
  11. C. G. Prosser, I. R. Fleet and A. N. Corps, J. Dairy Res., 1989, 56, 17 Search PubMed.
  12. B. G. Hammond, R. J. Collier, M. A. Miller, M. McGrath, D. L. Hartzell, C. Kotts and W. Vandaele, Ann. Rech. Vét., 1990, 21(Suppl. 1), 107 Search PubMed.
  13. P. G. Campbell and C. R. Baumrucker, J. Endocrinol., 1989, 120, 21 Search PubMed.
  14. C. E. Grosvenor, M. Frances Picciano and C. R. Baumrucker, Endocr. Rev., 1992, 14, 710 Search PubMed and references cited therein.
  15. C. R. Baumrucker, W. M. Campana, C. A. Gibson and D. E. Kerr, Endocrine Regul., 1993, 27, 157 Search PubMed.
  16. W. F. Blum and B. H. Breier, Growth Regulation, 1994, 4(Suppl.), 11 Search PubMed.
  17. B. H. Breier, B. W. Gallaher and P. D. Gluckman, J. Endocrinol., 1991, 128, 347 Search PubMed.
  18. P. Bang, R. C. Baxter, W. F. Blum, B. H. Breier, D. R. Clemmons, K. Hall, R. L. Hintz, J. M. P. Holly, R. G. Rosenfeld and J. Zapf, Endocrinology, 1995, 136, 816 Search PubMed.
  19. J. M. P. Holly and S. C. Cwyfan Hughes, J. Endocrinol., 1994, 140, 165 Search PubMed.
  20. Commission Decision, 93/256, 1993, No L 118/64.
  21. D. Schams, P. Matzke, P. Hollwich and H. Karg, Z. Ernährungswiss, 1990, 29, 154 Search PubMed.
  22. M.-L. Scippo, G. Degand, A. Duyckaerts and G. Maghuin-Rogister, Ann. Méd. Vét., 1997, 141, 381 Search PubMed.
  23. A. Berrini, V. Borromeo and C. Secchi, Hybridoma, 1994, 13, 485 CAS.
  24. C. M. Zwickl, H. W. Smith, R. N. Tamura and P. H. Bick, J. Dairy Sci., 1990, 73, 2888 Search PubMed.
  25. P. J. Eppard, G. J. Rogan, B. G. Boysen, M. A. Miller, R. L. Hintz, B. G. Hammond, A. R. Torkelson, R. J. Collier and G. M. Lanza, J. Dairy Sci., 1992, 75, 2959 Search PubMed.
  26. W. S. Cohick, M. A. McGuire, D. R. Clemmons and D. E. Bauman, Endocrinology, 1992, 130, 1508 Search PubMed.
  27. A. Devolder, R. Renaville, M. Sneyers, I. Callebaut, S. Massart, A. Goffinet, A. Burny and D. Portetelle, J. Endocrinol., 1993, 136, 91 Search PubMed.
  28. S. L. Davis, N. B. Wehr, D. M. Laird and A. C. Hammond, J. Anim. Sci., 1994, 72, 1719 Search PubMed.
  29. Cornell Research Foundation, Int. Pat., G01N 33/06, 1997 Search PubMed.
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