Feed additives and feed efficiency in the pork industry

1. Feed additives and feed efficiency in the pork industry F.R. Dunshea1,2 1CRC for High Integrity Pork; 2Department of Agriculture and Food Systems, Melbourne School of Land and Environment, The University of Melbourne, Parkville, VIC 3010;

2. We need technology https://www.elanco.com/Content/pdfs/2011_11068_Three-Rights-White-Paper-Revision_AI11224.pdf

3. Some technologies • Porcine somatotropin (pST, Reporcin) • β-agonists (ractopamine, Paylean) • Dietary additives • Cysteamine • Chromium • Betaine • Neuroleptics • Immunization against GnRF (Improvac) • Beta agonists (ractopamine, Paylean) • Orally active metabolic modifier

4. Metabolic modifiers • Porcine somatotropin (pST, Reporcin) • Recombinant peptide hormone • Daily (or less frequent) injectable • Beta agonists (ractopamine, Paylean) • Orally active metabolic modifier

5. Introduction Wray-Cahen et al. 1998

6. Daily pST injections increases daily gain (data 16 farms across Australia) Dunshea 2005

7. Daily pST injections decreases FCR (data 16 farms across Australia) Dunshea 2005

8. MWF pST injections decreases FCR Hellams et al 2000

10. Metabolic modifiers • Beta agonists (ractopamine, Paylean) • Orally active metabolic modifier

11. Ractopamine increases daily gain (5 ppm for 14 d followed by 10 ppm for 17 d) Rikard-Bell et al. (2009a)

12. Ractopamine decreases feed:gain (5 ppm for 14 d followed by 10 ppm for 17 d) Rikard-Bell et al. (2009a)

13. Effect of feeding ractopamine for 4 weeks without or with daily pST for last 2 weeks on FCR Rikard-Bell et al. (2009b)

14. Paylean for 4 weeks plus 4 pST injections over last 2 weeks decreases feed:gain Paylean for 4 weeks plus 4 pST injections over last 2 weeks decreases feed:gain van Barneveld et al. (2009)

15. Introduction Wray-Cahen et al. 1998

16. Introduction Cysteamine Wray-Cahen et al. 1998

17. Cysteamine • Cysteamine hydrochloride (CSH) increases ST secretion in rats • Mechanism appears to be through inhibition of somatostatin (SRIF) secretion • Responses are not as pronounced as pST and may be transitory • Further work is required to optimise the dose and timing as high doses may blunt the response more rapidly through inhibition of gherelin

18. Cysteamine at 70 ppm increases ADG

19. Response to Cysteamine (70 ppm) is not as great as pST Dunshea 2007

20. Cysteamine (70 ppm) and pST decrease fat Dunshea 2007

21. Cysteamine • Cysteamine hydrochloride (CSH) increases ST secretion in rats • Mechanism appears to be through inhibition of somatostatin (SRIF) secretion • Responses are not as pronounced as pST and may be transitory • Further work is required to optimise the dose and timing as high doses may blunt the response more rapidly through inhibition of ghrelin

22. Introduction Wray-Cahen et al. 1998

23. GRF (GHRH) and other neonatal manipulations Gallagher 2000

24. Neonatal treatment with pST can increase weaning weight and subsequent growth Dunshea (unpublished)

25. Neonatal treatment with pST can increase slaughter and carcass weight Dunshea (unpublished)

26. Introduction Chromium Wray-Cahen et al. 1998

27. Chromium • Chromium is an essential element that improves insulin activity • The digestibility and availability of Cr is low and variable (0.5-2% for inorganic Cr and 10-25% for organic) • Responses to dietary Cr have been variable, possibly because of poor and variable digestibility

28. Dietary Cr increases ADG but the response is variable (31 studies) Sales and Jancik 2011

29. Nano- and micro- chromium • Chromium is an essential element that improves insulin activity • The digestibility and availability of Cr is low and variable (0.5-2% for inorganic Cr and 10-25% for organic) • Responses to dietary Cr have been variable, possibly because of poor and variable digestibility • Reducing the Cr particle size may improve responses

31. Dietary Cr increases carcass weight Hung et al. 2011

32. Dietary Cr reduces backfat in very lean pigs Hung et al. 2011

33. Dietary nano CrPic increases the expression of muscle PI3K (an insulin signalling gene) Hung et al. 2011

34. Betaine • Betaine is an osmoregulator that reduces maintenance energy requirements • Improved pigs can be limited by DE intake • Responses to metabolic modifiers may be limited by DE intake • Betaine may provide additional energy for protein deposition in pigs

35. Betaine and pST have additive effects on daily gain in boars fed 80% ad libitum Betaine P=0.049 pST P<0.001 c c b a Suster et al. (2006)

36. Betaine and xylanase have additive effects on daily gain in gilts fed 80% ad libitum (2.7 kg/d) Dunshea (unpublished)

37. Dietary neuroleptics may improve growth of boars • Performance of group-housed entire males over the late finishing period is less than potential, possibly because of aggressive and sexual behaviours • Dietary neuroleptics (and immunization against GnRF) offer a means of reducing sexual and aggressive behaviours

38. Dietary neuroleptics may increase carcass growth Dunshea et al. 2011

39. Immunological castration (Improvac) • Physical castration of male pigs results in reduced feed efficiency and lean deposition and excess deposition of fat • Performance of group-housed entire males over the late finishing period is less than potential, possibly because of aggressive and sexual behaviours • Immunization against GnRF offers a means of reducing boar taint and negative behaviours and improving growth performance over that of both entire and physically castrated males

40. Entire males deposit more lean than physically castrated barrows during finishing Entire Barrow Suster et al. (2006)

41. Physically castrated barrows are fatter than entire males at 150 days of age Suster et al. (2006)

42. Physically castrated barrows are less efficient than entire males (ca. 11%) from weaning to market

43. I Smell Boar Taint!

44. Sexual development in the boar Hypothalamus GnRF  boar taint & sexual & aggressive activities Pituitary  LH & FSH  steroids such as testosterone & androstenone Testes

45. Immunization against GnRF (with Improvac) arrests/reverses sexual development in the boar Anti-GnRF Hypothalamus GnRF  boar taint & sexual & aggressive activities Pituitary  LH & FSH  steroids such as testosterone & androstenone Testes

46. Immunocastration reduces testes size Primary Secondary Dunshea et al. (2001)

47. Plasma testosterone declines rapidly and remains low for upto 8 weeks Dunshea et al. (2008)

48. Fat androstenone declines rapidly and remains low for upto 8 weeks Dunshea et al. (2008)

49. Castration and immunocastration eliminate boar taint Dunshea et al. (2001)

50. Dunshea et al. (2011)