1. Improving piglet survival in large litters Flemming Thorup DVM, Ph. D.

2. Danish Pig Production Is lead by a board of pig producers Secretariat Breeding department (DAN bred) Veterinary department Dept. for Barn (equipment) and Production Systems Department for Feeding and Reproduction Feeding of weaners and finishers Reproduction Quality of boar semen AI techniques Feeding of sows Sow longevity Female reproduction

3. Objects On farm investigations Large scale balanced comparative studies Observational studies Report writing Presentations Advisers, technicians, veterinarians, farmers, co-workers Information Teaching Vet. and anim. sci. students, graduation projects Handling general problems Herd problems

4. Improving piglet survival in large litters

5. Production herd results 1992-2005

6. Development 1992-2005 Year19922005 Total born per litter11,514,6 Still born, per cent611 Piglet mortality, per cent1215 Weaned per sow9,511

7. Piglet age at death 11 per cent mortality 15 per cent mortality

8. Most piglets die during the first 3-5 days Not much time to save the piglets - or Only 3 days of work to save the piglets?

9. Causes of mortality, percent of dead Cause13 per cent mortality 9 per cent mortality Crushed6465 Sepsis510 Small at birth67 Starvation115 Diarrhea42 Hernia23 Bleeding02 Arthritis12 Splayleg10 Malformation02 Miscellaneous75

10. Primary diagnosis for crushed piglets? Autopsy Number of piglets Herd 1Herd 2 Coagulum in ventricle 5321 Empty ventricle19

11. Causes of mortality Crushed-crushed-crushed and weak What comes first? Sepsis?

12. Mortality with increasing litter size

13. Number at birth. Effect on mortality.

14. Late born piglets have the highest postnatal mortality Increase from 9-12 No increase from 12 to 18? Late born piglets have to fight more for milk (Barnes and Quainoo, IPVS 1982)

15. Antibody level and mortality Ig 12 hours after birth

16. Antibody level 12 hours after birth Average 45 g/liter Large variations between piglets 0 at 12 hours = death 5 to 10 at 12 hours = hope for survivial 15 to 55 at 12 hours = fair chance > 55 = will survive > 20 per cent of the piglets

17. 0 2 4 6 8 10 12 0,30,50,70,91,11,31,51,71,92,12,32,5 Birth weight, kg Per cent of live born piglets Distribution of birth weights

18. Weight at birth and mortality 0 10 20 30 40 50 60 70 80 0,50,70,91,11,31,51,71,92,12,3 Birth weight, kg Mortality, per cent. 4,5 per cent 6,0 per cent 2,5 per cent 13,0 per cent

19. Underweight piglets and litter size

20. Piglet mortality The piglets die by crushing - during the first days They are the smallest piglets They are the last born piglets They are the piglets with a low antibody intake Piglets going to be crushed can be predicted at birth Piglets that are going to survive can be predicted at birth Most piglets are in between!

21. Effect of birth weight and birth order on mortality Birth weight< 1 kg≥ 1 kg Number of piglets29173 Mortality, per cent455

22. Effect of birth weight and birth order on mortality Birth weight< 1 kg≥ 1 kg Number of piglets29173 Mortality, per cent455 Birth order1-7> 71-7> 7 Number of piglets131610172 Mortality, per cent87538

23. Birth weight, birth order and Ig Birth weight<1 kilo≥ 1 kg No. at birth1-7>71-7>7 Piglets, no.13149971 Deaths, no.11035 Low Ig, no.0413 Low Ig means < 10 gram/liter. (Average = 45 gram/liter)

24. Hypotheses for piglets born in large litters The first born piglets have readily access to colostrum and milk The last born piglets must compete with the fortunate first born piglets The smallest piglets loose this competition

26. Solution Litter size must be adjusted Moving piglets to small litters Using nurse sows When? After colostrum uptake Before the piglets die Before ranking

27. Colostrum uptake Registration of birth order and birth weight Assay 12, 24 and 48 hours after birth Assay for non specific Ig’s Registration of mortality until weaning

28. Effect of birth order

29. Effect of birth weight

30. What is the optimal nurse sow for 12 hours old piglets? Parity A second to fourth litter sow have the highest milk production Stage of lactation Milk composition Increasing or decreasing production Empty period Milk pressure, motivation or forgetting her own piglets? Accept of piglets Relaxants Oxytocin

31. One step nurse sow 21 day old piglets New born piglets

32. Two step nurse 21 day old piglets 7 day old piglets New born piglets

33. One or two step nurse? One step nurse 21 day lactation Two step nurse 7 day lactation AvailableEasyMore work Double risk Acceptance of new piglets ??? Milk productionDecreasingIncreasing Milk qualityHigh

34. Set up of trial Collecting pairs of newborn piglets after colostrum-uptake All piglets were earmarked and weighed One piglet stayed with the mother One piglet went into the trial

35. Nurse sows Piglets randomly entered a one step or a two step nurse sow All nurse sows were 1. Litter sows Both nurse sows had an equal profile Number of piglets born Number of piglets weaned Lactation length Video for 24 hours Mortality and weight at weaning was recorded

36. Results One step nurseTwo step nurse Litters 10 Piglets 110 Hours to first nursing 75 Mortality, % 18 a 6b6b Weaning weight, kg 5,5 a 6,4 b

37. Results Control pigletsOne step nurse Two step nurse Litters 20110 Piglets 220110 Hours to first nursing (40 minutes)75 Mortality, % 6b6b 18 a 6b6b Weaning weight, kg 6,3 b 5,5 a 6,4 b

38. Two step nurse 21 day old piglets 7 day old piglets New born piglets

39. The first step piglets Piglets earmarked and weighed at transfer at 7 days and at weaning Compared with a similar litter not transferred

40. Transferred two step nurse piglets Transferred piglets Piglets not transferred Litters10 Piglets119116 Age at transfer/control 7,26,1 Weight at transfer/control 2,22,3 Mortality, %3,46 Weaning weight, kg6,3 6,7

41. Gilts or sows as nurse sows 1. Litter sows2.-5. Litter sows Litters12 Piglets124126 Mortality, %12 a 28 b Weaning weight, kg 6,97,1

42. Piglet mortality at first litter or older nurse sows.

43. 11 or 13 piglets per litter? 31 pairs of sows with 24 piglets Piglets were app. 24 hours old 11 and 13 piglets were allocated to the two sows No transfer of piglets after allocation Piglets at both sows were weaned at the same day

44. 11 or 13 piglets per litter? Litter size 1113 Litters 31 Mortality 8,2*10,2* Weight per piglet 7,7 a 7,1 b Piglets weaned 313363 * P = 0,08

45. Trial Ensuring colostrum to the smallest piglets Control Adjusting litter size after 12 hours Small or large piglets could be transferred Trial Reducing litter size to 10 after 6 hours by removal of the largest piglets Adjusting litter size after 12 hours Small or large piglets could be transferred

46. Ensuring milk to the smallest piglets ControlTrial Size Weight in kilo Small 0,5 -1 Large 1,1-2,4 Small 0,5 -1 Large 1,1-2,4 Isolated part of ”large” Number6441474419161 Mortality28*1034*87 Transferred3422153468 * A difference of 15 per cent would be significant.

47. Ensuring milk to the smallest piglets No effect on the survival of the smallest piglets, when reducing the litter to 10, to ensure colostrum to the smallest piglets. Were there an effect of removing (collecting) the smallest piglets? Is mortality in small piglets primarily a cause of lack of sows milk? Large piglets may be removed from the mother after 6 hours

48. Conclusions Crushing may be the visible cause of death, but a number of precursors seems to exist Understanding these precursors may lead into ways of reducing piglet mortality

49. A number of other management factors have been shown to reduce piglet mortality, eg. observation during and after birth, drying off small piglets, climate control, vaccinations and treatments of disease. Intensive daily care must be continued, when introducing new strategies in the farrowing department.

51. Ekstra

52. Underweight piglets Undernourished during pregnancy (IPVS) Heat loss after birth (Hoy, …). Better survival when small piglets were collected at a nurse sow. (Straw et al. 1998)

53. Body temperature with and without drying of the piglets. Hoy, 2003? Rectal temperature (°C)p < 0,01 Minutes after birth n = 117 n = 52

54. Routes of newborn to first uddercontact (Bünger 1983) Main routes Most frequent routes of mistakes

55. A two step nurse is the nurse sow at choice 21 day old piglets 7 days old piglets New born piglets

56. Survival by litter size Overvejes, kun pct. levf.

58. Effect of birth number

59. Effekt of IGG on mortality

60. Birth weight versus piglet survival

61. Liveborn piglets with increasing litter size

63. Colostrum intake by birth weight

64. Colostrum intake by birth order

65. Ig in colostrum after birth

66. No. weaned piglets when increasing total born piglets