Reproduction management for longevity
Dr Carel Muller
Western Cape Department of Agriculture,
Institute for Animal Production, Elsenburg
Dairy Information day
28 Augustus 2012
Elsenburg
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
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
Reasons for culling cows:
40
35
30
Cows culled (%)
25
20
15
10
5
0
Injury
Legs
Died
Sold
Culling reasons
Mastitis
Production
Reproduction
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
2500
200
2250
190
180
2000
170
1750
160
1500
150
1250
140
1000
130
750
120
500
250
4-Okt-06
110
13-Des-06
21-Feb-07
2-Mei-07
Date
11-Jul-07
18-Sep-07
100
25-Nov-07
Cows in milk
Milk yield (kg/day)
Real case scenario:
Commonly used indicators:
1.
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
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
Possible traits to describe fertility:
Definition
Description
Traits
1. Coming on
heat soon
after calving
When is first AI?
1. C-1st AI (d)
2. C-1st AI<80DIM
2. Conceive
from few AI’s
Number of
1. AI’s/con
AI’s/conception 2. PD 1st AI
3. Breeding period (d)
4. Heat interval (d)
3. Staying
pregnant
until next
calving
When did cows
become
pregnant?
1. Interval DO (d)
2. DO < 100 days
3. DO < 150 days
4. DO < 200 days
5. Calving interval (d)
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)
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
•
Excel spreadsheet for Elsenburg cows
Excel spreadsheet results:
Herd parameters
PD parameters
AI parameters
# CIH
218 PD dry (%)
100
All AI's/con
3.19
# CIM
188 PD>100d (%)
59
Efficiency (%)
% CIM
86 PD>200d (%)
80
AI's/con
Ave Lact nr
2.98 ND>201 DO(%)
20
AI efficiency (%)
49
DIM (d)
162 PD<100 DO(%)
44
PD1stAI (%)
49
PD<200 DO(%)
91
C-1stAI (d)
83
DO (d)
126
1stAI<80dim (%)
56
Exp ICP (d)
405
31
2.04
SA Holstein herds vs. Australian survey:
Parameters
C-1st AI<80DIM
(%)
AI’s/con
Ave
InCalf project
14 Herds
>9000
Range
cows
(min – max) Good Problems
61
2.48
36 - 89
73
<61
1.96 - 3.33
1.96
>2.32
AI efficiency (%)
40
30 - 51
51
<43
PD100 DO (%)
42
21 – 50
58
<45
PD200 DO (%)
83
58 - 90
87
<81
Cows confirmed pregnant >100 and >200 DIM:
PD>100d
PD>200d
100
90
Cows pregnant (%)
80
70
60
50
40
30
20
10
0
1
5
9
13
17
21
25
29
Monthly PD checks
33
37
41
45
Conception date affects monthly calving rate (%):
0.14
Monthly calving rate (%)
0.12
0.10
0.08
0.06
0.04
0.02
0.00
Conception date
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
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
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
Long term work plan:
• Start using AI bulls with high EBV’s for Daughter Pregnancy rate/
Productive life
• Use calving ease bulls for heifers
•
Thank you for your attention
•
Good luck
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
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
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
Results: Genetic and residual correlations:
Genetic (above) and residual (below) correlations
FS80d
PD100d
PD200d
-
0.54±0.16
0.60±0.15
PD100d
0.42±0.17
-
0.95±0.20
PD200d
0.12±0.02
0.97±0.02
-
DO
0.06 – 0.07
0.56±0.11
0.03±0.01
CFS
0.28±0.01
0.04 – 0.08
0.99±0.19
SPC
0.04±0.01
0.81±0.02
0.06 - 0.10
Traits
FS80d
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
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
Example - Reproduction records of 5 cows (3):
Cow
Breeding
period (d)
3588
4005
4009
4015
4019
All AI’s
Average
days (d)
HDR %
27
1
27
0.78
129
2
65
0.33
41
1
41
0.51
124
4
31
0.68
150
2
75
0.28
154
3
51
0.41
102
2
51
0.41
108
2
54
0.39
61
2
31
0.69
175
5
35
0.60
Example - Reproduction records of 5 cows (2):
Cow
SPC
PD 1st AI
DO (d)
PD<100d
3588
1
1
59
1
1
1
2
0
161
0
0
1
1
1
73
1
1
1
4
0
156
0
0
1
2
0
182
0
0
1
3
0
186
0
0
1
2
0
134
0
1
1
2
0
140
0
1
1
2
0
93
1
1
1
5
0
207
0
0
0
4005
4009
4015
4019
PD<150d PD<200d
Example - Reproduction records of 5 cows (1):
Cow
C-date
3588
4005
4009
4015
4019
Lact nr
AFC (m)
CFS (d)
CFS < 80d
26/04/2006
1
28.3
59
1
31/03/2007
2
138
0
23/02/2006
1
73
1
27/01/2007
2
67
1
11/02/2006
1
120
0
9/05/2007
2
94
0
3/03/2006
1
101
0
18/04/2007
2
98
0
22/03/2006
1
73
1
28/03/2007
2
60
1
25.3
24.7
25.2
25.6
CFS and DO as affected by year of calving:
CFS (d)
DO (d)
180
160
Number of days
140
120
100
80
60
40
20
0
1991
1993
1995
1997
1999
Years
2001
2003
2005
2007
CFS and DO differences between herds:
CFS (d)
DO (d)
200
Number of days
150
100
50
0
1
2
3
4
5
6
7
8
Herds
9
10
11
12
13
14
SPC as affected by herd:
3.5
3.0
Services per conception
2.5
2.0
1.5
1.0
0.5
0.0
1
2
3
4
5
6
7
8
Herds
9
10
11
12
13
14
FS80d and PD100d as affected by year of calving:
FS80d
PD100d
80
70
Percentage of cows
60
50
40
30
20
10
0
Year of calving