State of the art in conventional AI on Danish farms

1
BPEX AI meeting

• State of the art in conventional AI on Danish
  farms
• ___
• Mads Thor Madsen
• DVM, Certificate in Swine Herd Health
• 14th of February 2005

2
Agenda BPEX AI-meeting

• Welcome and presentation
• Rules for Danbred AI stations
• AI research projects preliminary results
• State of the art in conventional AI
• Future co-operation

3
Heat detection
Ovulation
Riding test
Strenght of heat
Riding test 4 boars
Time
Mounting
No mounting
(mod.e. Langendijk et al.)
4
Heat detection
5
Heat detection
6
Heat detection
7
Heat detection
8
Heat detection
9
Average and interval of oestrus duration and time
of ovulation after onset of heat
10
Optimal insemination
Total born piglets per litter
Total born
n 75
X 12,8 (4-25)
Ref. Anne Kirstine Nissen, 1995
11
Optimal insemination
12
Optimal insemination
13
Optimal insemination
14
Optimal insemination heat detection scheme
15
Human stimulation

• Oxytocin - lab trial
• Investigated with 3 groups of sows
• high stimulation
• low stimulation
• mating with boar (control)
• Blood sampling and hormone analysis
• All sows had the possibility of nose contact with
  a boar

16
Human stimulation
17
Human stimulation

• Oxytocin Herd trial
• Investigated with 2 groups of sows
• high stimulation
• low stimulation
• Farrowing rate and total born piglets per litter

18
Human stimulation

• Oxytocin Herd trial
• Farrowing rate a difference of 5.9 in favour
• of the high stimulation group
• No difference in total born piglets per litter

19
Stress and implantation

• Implantation defined as day 0 34 after first
  insemination
• Stress in part of the implantation will result in
  loss of embryos or return to oestrus
• When and what stressors - we do not know?

20
Stress and implantation

• Transport of embryos high stress
• Day 10 12 maternal contact low stress
• Day 12 14 embryo production of estrogens low
  stress
• Until day 16 low immune response low stress
• Until day 25 heat stress causes death of
  embryos

21
Stress and implantation

• Conclusion
• A Danish average sow will be most sensitive
• to stress day 10 25 of the implantation period

22
Stress and implantation

• Stress releases a hormone from the pituitary
  gland
• The hormone consists of ACTH and beta-endofine
• ACTH releases cortisol and adrenaline, while
  beta-endofine is the problem
• Beta-endofine inhibits the hormone responsible
  for ovulation (LH)

23
Stress and implantation

• Direct stress lab trial
• Sows in 3 groups treated every 4 hours
• during oestrus with
• - CRH
• - ACTH
• - Saline
• Blood sampling and analyses of hormones

24
Stress and implantation

• Direct stress lab trial
• - Delayed LH peak and a more broad peak
• Delayed ovulation (8 hours)
• Unaffected length of heat (60 hours)

25
Stress and implantation
26
Stress and time after AI

• Herd trial
• Rest after AI in boxes in 2 groups of sows which
• were
• Within the box for at least 2 hours after AI
• Forced out of the box immediately after AI
• Farrowing rate and total born piglets per litter

27
Stress and time after AI

• Herd trial
• No difference overall between the 2 groups
• in farrowing rate and total born piglets per
  litter
• But age dependent !

28
Stress and time after AI
29
Stress and time after AI
Farrowing rate and age
30
Stress and time after AI
Total born piglets per litter and age
31
Strategic use of boar at stimulation

• Herd trial
• Investigated with 2 groups of sows
• - Constant boar contact
• - Only boar contact the first 2 days after
  weaning and at the day of expected insemination
• Farrowing rate and total born piglets per litter
• Time for heat detection and insemination

32
Strategic use of boar at stimulation

• No differences in farrowing rate and total born
• piglets per litter
• Reduction of time for heat detection and
• insemination (approx. 2 minutes) in favour of
• the low boar exposed group

33
Miscellaneous

• Avoid blood on tip of catheter
• Avoid the use of catheter gels
• Avoid preheating of semen before use
• Use a higher concentration of Yorkshire semen
  when used on Yorkshire sows
• Use a shorter life-span when using Hampshire
  semen
• Re-inseminate if peristaltic contractions (2
  hours later)
• Boars for smell has to be gt 10 month of age

34
Prostaglandin (PGF2alfa) release during AI

• PROSTAGLANDIN TRIAL
• Investigated with 3 groups of sows
• high stimulation
• low stimulation
• boar stimulation
• Blood sampling and analyses of hormones

35
Prostaglandin (PFG2alfa) release during AI