xx international grassland conference 2005 (1) 2005 genetic alternatives for dairy producers who...

XX International Grassland Conference 2005 (1) 2005

Genetic Alternatives for Dairy Producers who Practise Grazing

H. D. Norman, J. R. Wright, R. L. Powell

Animal Improvement Programs LaboratoryAgricultural Research Service, USDABeltsville, MD 20705-2350

[email protected] 301-504-8334

What genetic programs work well for U.S. graziers?

XX International Grassland Conference 2005 (2)


Grazier breeding

Objective

– Cattle with better fertility or other desired characteristics

Approaches (occasional use)

– Bulls from countries that practise grazing

– Bull breed different from cow breed

– Effectiveness?


Phenotypic trend in days open

100

120

140

160

65 70 75 80 85 90 95 00

Year

Day

s open

12345

Lactation


Comparison

Daughter performance within herd

– New Zealand AI Holstein or Friesian bulls

– Other AI Holstein bulls (predominantly U.S.)

Cows included

– Records in AIPL national database

– Calved before March 2004

– Time to express the performance traits


Yield and SCS data

First-lactation daughters (149 herds)– 489 sired by New Zealand bulls– 5419 sired by U.S. bulls

Second-lactation daughters (126 herds)– 345 sired by New Zealand bulls– 5057 sired by U.S. bulls

Third-lactation daughters (78 herds) – 174 sired by New Zealand bulls– 2840 sired by U.S. bulls


Yield results

Milk U.S. daughter superiority– First lactation 501 kg***– Second lactation 467 kg***– Third lactation 448 kg***

Fat New Zealand daughter advantage– First lactation 2 kg– Second lactation 2 kg– Third lactation 2 kg

Protein U.S. daughter superiority/advantage– First lactation 5 kg**– Second lactation 5 kg* – Third lactation 4 kg


Economic value

Current U.S. milk prices

MFP$ = 0.012 milk + 1.30 fat + 2.30 protein

U.S. daughter MFP$ advantage– First lactation $35.09– Second lactation $30.83– Third lactation $28.39


SCS results

First lactationU.S. daughter advantage of 0.1

Second lactationU.S. daughter superiority of 0.2***

Third lactationU.S. daughter advantage of 0.2


Days open data

First-lactation daughters (138 herds)– 450 sired by New Zealand bulls– 5036 sired by U.S. bulls

Second-lactation daughters (112 herds)– 311 sired by New Zealand bulls– 4781 sired by U.S. bulls

Third-lactation daughters (68 herds) – 146 sired by New Zealand bulls– 1939 sired by U.S. bulls


Days open results

First lactationNew Zealand daughter superiority of 7 days*

Second lactationU.S. daughter advantage of 2 days

Third lactationU.S. daughter advantage of 3 days


Type data

First-lactation daughters (42 herds)

– 76 sired by New Zealand bulls

– 376 sired by U.S. bulls


Type results

Size compositeNew Zealand daughters smaller by 0.91 points***

Udder compositeU.S. daughter advantage of 0.79 points

Foot compositeU.S. daughter superiority of 0.68 points**


Conclusions

Strain differences between U.S. Holsteins and New Zealand Friesians for several traits

Higher milk and protein yields for U.S. bull daughters

Lower first-lactation SCS for U.S. bull daughters


Conclusions (continued)

Fewer first-lactation days open for New Zealand bull daughters

Smaller body size for New Zealand bull daughters

Better feet for U.S. bull daughters


Caution

All strain differences influenced by individual bulls chosen from each country


Recommendations to breeders Don’t select bulls solely on one trait

because many traits have economic value

Consider economic value of all performance traits in your own market when making genetic choices

For seasonal calving, use an index that puts more weight on daughter fertility than those recommended for the general industry


Alternative approaches

Comparisons needed

–Productive life

–Crossbreds

Advantages of either alternative


Crossbreeding

Heterosis

–Milk 3.4%

–Fat 4.4%

–Protein 4.1%

–SCS 0.7%

–Days open 1.8%


Thank you!

xx international grassland conference 2005 (1) 2005 genetic alternatives for dairy producers who...

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