Reproduction management for longevity Dr Carel Muller Western Cape Department of Agriculture,

1. Reproduction management for longevity Dr Carel MullerWestern Cape Department of Agriculture, Institute for Animal Production, Elsenburg Dairy Information day 28 Augustus 2012 Elsenburg

2. Introduction (1) : • Longevity of cows is dependant on reproductive ability • Poor reproduction results in: - higher culling rate of cows - reduced productive life - higher replacement cost • Less obvious effects: - higher average DIM - lower average lactation number - lower milk production - loss in farm income

3. Introduction (2): • In SA selection programmes focused on milk yield and conformation traits • No emphasis on improving fertility in dairy cows • At best, cows not pregnant, are culled • Usually after an extended, costly breeding programme • Internationally fertility of bull daughters has only recently received attention • In SA EBV for calving interval are estimated

4. Reasons for culling cows:

5. Understand the big picture: • Lack of understanding between the interaction between reproduction and daily milk yield • Working with large numbers of animals there is often a difference between perception and facts • A low milk yield today could be because of poor reproduction management a year ago • Lower milk yield due to: - Extending lactation increases DIM - more cows in late lactation - High culling rate increases % first lactation cows

6. Real case scenario:

7. Commonly used indicators: • Calving interval: - historical information - only accounts for cows calving down again - cows not calving again adds no data to the calculation for herd average - include interval between c-date – today’s date 2. AI’s/conception: - indication of inseminator efficiency - what if days open is 150 days? • Suggest farmers/consultants/veterinarians are not using appropriate dairy cow fertility indicators

8. What is cow fertility: • It’s more than getting cows pregnant (eventually) Fertility definition: - the ability to come on heat soon post calving - conceive with minimum number of inseminations - carry a calf full term and - calve down successfully delivering a healthy calf • Each trait is greatly affected by management

9. Possible traits to describe fertility:

10. Records required for each cow: • Calving date • Lactation number • Status (lactating=1 or dry=0) • Insemination dates (first and most recent) • Results from pregnancy checks (Yes/No)

11. Next step: • Put on a spread sheet • Convert dates to intervals • Add binomial traits (yes=1, no=0) • Update after each vet visit • Base decisions on information from the list

12. Excel spreadsheet for Elsenburg cows

13. Excel spreadsheet results:

14. SA Holstein herds vs. Australian survey:

15. Cows confirmed pregnant >100 and >200 DIM:

16. Conception date affects monthly calving rate (%):

17. A work plan for reproduction management: • Determine the reproductive status of the dairy herd – from a list of all cows in the herd with relevant information • Compare to available norms and standards • Start monthly herd visits for fresh cows and pregnancy tests • Have short, medium and long term work plans

18. Short term work plan: • Check pregnancy of cows >100 DIM • Sell cows not pregnant that are dry and more than 300 DIM • Check all cows for sexual activity 42 days after calving • Treat non-active cows • Start monitoring cows during the first 10 days after calving • Follow a treatment programme for cows with retained placentas, uterine infections, etc. • Start using a clean, dry and sunny maternity area

19. Medium term work plan: • Decide what to do with cows not pregnant >150 DIM – bull or synchronisation programme • Put cows on a steam-up feeding programme • Start with a heat detection programme, use markers • Check AI technique/success rate of inseminators • Check semen quality of AI semen • Check feet, legs and semen quality of service bull

20. Long term work plan: • Start using AI bulls with high EBV’s for Daughter Pregnancy rate/ Productive life • Use calving ease bulls for heifers

21. Thank you for your attention • Good luck

22. Genetic study for fertility traits: Two outcomes: 1. Evaluate alternative fertility traits to CI - establish level of reproduction management 2. Estimate genetic parameters for fertility traits - identify fertile cows

23. Materials and Methods: • Reproduction records from 14 Holstein herds of 9046 cows calving in 24646 lactations - calving dates - lactation number - AI dates (n=69180) - pregnancy check results • Determine interval traits • Establish binomial status for intervals traits

24. Interval traits: • Calving date to first AI date (CFS) • Calving date to conception date (DO) • Number of AI’s/conception • Binomial traits: - CFS <80 DIM - Pregnant <100 days - Pregnant < 200 days - Pregnant from first AI

25. Results: Genetic and residual correlations:

26. Conclusion (1): • Alternative fertility traits are available • Genetic correlations indicate possible traits to be used: • Best traits: - C-1stAI, - DOPEN and - AI’s/conception • Wide genetic variations between cows gives scope for selection

27. Conclusion (2): • Must accept that management has a large effect on traits • Poor management extends intervals – seen as less fertile or unfertile cows • Fertility aids improves reproduction management – observed as fertile cows

28. Example - Reproduction records of 5 cows (3):

29. Example - Reproduction records of 5 cows (2):

30. Example - Reproduction records of 5 cows (1):

31. CFS and DO as affected by year of calving:

32. CFS and DO differences between herds:

33. SPC as affected by herd:

34. FS80d and PD100d as affected by year of calving: