1. Lifetime Performance of Dairy Cows in Northern Ireland
Dr David Mackey
Greenmount Campus, CAFRE
Aug 2009

2. BACKGROUND - Government
Developing technologies to improve the fertility of dairy cows - AC0205
Description
The number of cows in the national herd is the main driver for environmental impact of dairy farming. Genetic increases in milk yield are predicted to continue, so cow numbers and environmental impact might be expected to continue falling. However, poor fertility is hampering progress by reducing lifetime yield per cow. In addition, outputs of methane, nitrogen and phosphorus during the rearing phase are spread over fewer units of lifetime milk production. Thus, it is important that the fertility issue is addressed urgently.

3. BACKGROUND – Welfare lobby
COWS ARE MILKED BEYOND ENDURANCE – July 2009
Selective breeding of dairy cattle has led to a dramatic increase (50 per cent) in milk yield over the past 40 years.
Breeding and managing cows for high yield damages their health and decreases their average productive life. Modern dairy cows are often worked to the limit of their physical capacity, or beyond.
In the UK a cow has on average only three lactations before she is culled due to health or infertility problems, a much shorter lifetime than a suckler cow producing just enough milk for her own calf.
Infertility is an increasing problem in high-yielding cows and is linked to stress and loss of body condition because the cow is unable to keep up with the metabolic demands of milk production by enough intake of nutrition.
Studies have shown high proportions of cows are underweight and suffer from lameness and mastitis.

4. BACKGROUND – Milk Recording

5. BACKGROUND - NMR
Dairy Event 2009: Cows make profit from third lactation
17 Sep 2009
… the best parameter to measure technical sustainability is Lifetime Daily Yield (LDY) - the total milk a cow gives in her lifetime, divided by her age.
… LDY does not just reflect fertility parameters, but factors such as heifer rearing, infectious disease, mastitis, lameness, fertility, milk quality and nutrition, because of the impact they all have on conception rates and litres of milk sold. Therefore, it is an indicator of overall performance that farmers could check regularly to see if problems had crept in, before ‘digging down’ into the data to identify that problem.
… cows in the top 10 per cent of NMR-recorded herds are achieving litres per day, compared to a ‘terrifying’ 5.72 litres in the bottom 10 per cent. The average is around 11 litres per day.

6. BACKGROUND – CRV (Holland)
Dutch Cows Excel in Longevity
“In Sep 2009, the average production of Dutch cows once again broke the 30,000 kg barrier. With a lifetime production of 30,543 kg milk, production has remained stable compared to Longevity for all dairy cows in the Netherlands was 2,128 days – an average of 5 years and 10 months …
… CRV published the lifetime production in 2004 for the first time: 27,701 kg milk was the result. A few years later it increased by about 3,000 kg. This shows that breeding for longevity is rewarding!”

7. BACKGROUND - Technology Investigation: Lifetime Performance
One of Greenmount’s Future Herd targets is to achieve a lifetime performance of 40,000 litres/cow.
Target linked to research on breeding a more robust dairy cow.
How does this target compare with the current Northern Ireland average?
What are the attributes of herds with the highest lifetime performance?

8. ANALYSIS OF RECORDS ON LIFETIME PERFORMANCE
Dataset comprising lifetime performance of over 66,000 NI dairy cows acquired from United Milk Records/Holstein UK.
Analysis performed on 48,403 valid cow records from 680 herds.
Ranked herds by lifetime performance and divided into quartiles and 10% bands to establish attributes of herds with highest lifetime performance.

9. AVERAGE FINDINGS N. Ireland average Future Herd* CREAM Herd**
Lifetime yield (litres)
Average longevity (years)
Age at first calving (years)
Productive life (years)
Lifetime yield (l/day prod life)
Lifetime yield (l/day total life)
Lactation no. at culling
DIM at culling
Average calving interval (days)
27,600
6.1
2.5
3.6
21.5
11.1
259
423
36,322
6.3
2.0
4.3
23.3
15.8
218
395
39,876
5.6
2.2
3.4
33.7
16.9
256
426
*Greenmount Future Herd is 140-cow herd of commercial pedigree Holstein cows averaging around 8,000 litres/cow/year.
*Greenmount CREAM Herd is student-run 30-cow herd of high genetic merit Holstein cows averaging around 10,500 litres/cow/year.

10. DAILY LIFETIME YIELD CREAM Herd - 16.9 litres/day Future Herd
Northern Ireland average
litres/day

11. LIFETIME PERFORMANCE - Analysis of herds in 25% bands
Top
25%
Second
Third
Bottom 25%
No. herds
No. cows
Lifetime yield (litres)
170
12,186
35,269
14,311
29,632
13,357
24,804
8,549
17,770
Age at 1st calving (years)
Longevity (years)
Productive life (years)
2.37
6.71
4.35
2.42
6.15
3.73
2.49
5.87
3.38
2.63
5.26
DIM at culling
Lactation no. at culling
273
4.2
266
3.6
252
3.4
247
2.7
Lifetime fat%
Lifetime protein%
3.90
3.22
3.92
3.24
3.95
3.98
3.25
Average lactation yield (litres)
Lifetime yield (l/day total life)
Lifetime solids yield (kg)
Average calving interval
8,390
13.2
2,489
424
7,909
11.9
2,103
7,000
10.3
1,768
421
6,146
8.2
1,277

12. Lifetime Performance - Analysis of herds in 25% bands

13. LIFETIME PERFORMANCE - Analysis of herds in 10% bands

14. LIFETIME PERFORMANCE - Longevity vs lactation yield
The 68 herds comprising the 1st, 5th and 9th 10% band in previous slide (as indicated by arrows) were compared.
Herds with highest lifetime performance are achieving this through both longer longevity and higher average lactation yield, though at herd level there is a negative correlation between longevity and lactation yield.
Cows can achieve 40,000 litres as either:
5 lactations of 8,000 litres
8 lactations of 5,000 litres

15. SUMMARY
Lifetime performance of Future Herd (35,000 litres) exceeds Northern Ireland average of 27,600 litres.
While longevity similar to NI average, Future Herd has longer productive life as result of heifers calving earlier.
Herds with highest lifetime yield have:
- Higher average lactation yield
- Longer productive life ( longevity,  age at first calving)
In herds of similar lifetime yield:
- considerable variation in longevity and average lactation yield
- negative correlation between longevity and average lactation yield

16. ACKNOWLEDGMENTS
We would like to acknowledge both United Milk Records and Holstein UK for providing us with the data on which to conduct this technology investigation.

18. LIFETIME PERFORMANCE - Analysis of herds in 25% bands
Top
25%
Second
Third
Bottom 25%
No. herds
No. cows
Lifetime yield (litres)
170
12,186
35,269
14,311
29,632
13,357
24,804
8,549
17,770
Age at 1st calving (years)
Longevity (years)
Productive life (years)
2.37
6.71
4.35
2.42
6.15
3.73
2.49
5.87
3.38
2.63
5.26
DIM at culling
Lactation no. at culling
273
4.2
266
3.6
252
3.4
247
2.7
Lifetime fat yield (kg)
Lifetime protein yield (kg)
Lifetime fat%
Lifetime protein%
1,356
1,133
3.90
3.22
1,147
956
3.92
3.24
965
803
3.95
699
578
3.98
3.25
Average lactation yield (litres)
Lifetime yield (l/day prod life)
Lifetime yield (l/day total life)
Lifetime solids yield (kg)
Average calving interval
8,390
22.8
13.2
2,489
424
7,909
22.5
11.9
2,103
7,000
20.6
10.3
1,768
421
6,146
19.2
8.2
1,277

19. TECHNOLOGY INITIATION
In sample of 30 herds (10 from each group):
Reasons for culling
- infertility, mastitis, lameness, etc
Health benchmarking
Incidence of lameness
(involving AFBI lameness survey)
and locomotion scoring
Incidence of mastitis and herd SCC
(from monthly milk statements/milk recording)
Fertility Benchmarking – from Kingswood, FarmWizard, Sum-IT or paper records
Age at first calving – established already from cull cows but what is current herd average?
Establishment of herd genetic merit where pedigree registered - particularly PLI (that encompasses production, fertility, SCC and lifespan traits) and PTA for milk production (and how this relates to 305-day production).
Dairy Benchmarking – linking lifetime and financial performance

20. LIFETIME PERFORMANCE - Effect of year of culling

21. LIFETIME PERFORMANCE - Effect of year of birth

22. SUMMARY
Lifetime performance of Future Herd (35,000 litres) exceeds Northern Ireland average of 27,600 litres.
While longevity similar to NI average, Future Herd has longer productive life as result of heifers calving earlier.
Herds with highest lifetime yield have:
- Higher average lactation yield
- Longer productive life ( longevity,  age at first calving)
In herds of similar lifetime yield:
- considerable variation in longevity and average lactation yield
- negative correlation between longevity and average lactation yield
Of cows culled in last few years, tendency for increased lifetime yield and longevity in last few years.
However when analysed by year of birth, results suggest that longevity and lifetime yield may be declining.

23. Last completed lactation yield
BACKGROUND - NMR
Last completed lactation yield
Lifetime daily yield (LDY) comparison by lactation number.
Yield (kg/day of life)
Yield (kg/day of life)
Lactation no.