Czech J. Anim. Sci., 2005, 50(1):7-13 | DOI: 10.17221/3976-CJAS

Definition of subgroups for fixed regression in the test-day animal model for milk production ofHolsteincattle in theCzech Republic

L. Zavadilová, E. Němcová, J. Přibyl, J. Wolf
Research Institute of Animal Production in Prague, Czech Republic

The investigation was based on roughly 3.9, 2.7 and 1.7 million test-day records from first, second and third lactation, respectively, sampled from 596 200 Czech Holstein cows between the years 1991 and 2002. Breeding values were estimated from multi-lactation random-regression test-day models which contained the fixed effect of herd-test day, fixed regression on days in milk and random regressions on the animal level and the permanent environmental effect. Third degree Legendre polynomials (with four coefficients) were used for both the fixed and random regressions. The models differed in fixed regression. In Analysis I, 96 subclasses were defined according to age at calving, season and year of calving within lactation. In Analysis II, days open were additionally included as a grouping factor resulting in 480 subclasses. Rank correlations over 0.98 between both analyses were observed for breeding values for sires. Grouping according to Analysis I was recommended.

Keywords: test-day model with random regression; fixed regression subgroups; lactation curves; milk yield; dairy cattle

Published: January 31, 2005  Show citation

ACS AIP APA ASA Harvard Chicago Chicago Notes IEEE ISO690 MLA NLM Turabian Vancouver
Zavadilová L, Němcová E, Přibyl J, Wolf J. Definition of subgroups for fixed regression in the test-day animal model for milk production ofHolsteincattle in theCzech Republic. Czech J. Anim. Sci. 2005;50(1):7-13. doi: 10.17221/3976-CJAS.
Download citation

References

  1. Candrák J., Kadlečík O., Schaeffer L.R. (1997): The use of test-day model for Slovak cattle populations. In: Proc. 48th Annual Meeting of the European Association for Animal Production, Vienna, Austria, August 25-28.
  2. Dědková L., Jamrozik J., Schaeffer L.R. (2002): Genetic parameters for test-day model with random regressions for production traits of Czech Holstein cattle. In: XX. Genetické dny, 12.-13. 9. 2002, Brno. 117-121.
  3. Dědková L., Němcová E. (2003): Factors affecting the shape of lactation curves of Holstein cows in the Czech Republic. Czech J. Anim. Sci., 48, 395-402.
  4. Emmerling R., Dempfle L., Götz K.-U. (2000a): Validation of fixed effects in a test day model. In: Proc. 51st Annual Meeting of the European Association for Animal Production, August 21-24 2002, Den Haag, The Netherlands.
  5. Emmerling R., Lidauer M., Mäntisaari E.A. (2000b): Multiple lactation random regression test-day model for Simmental and Brown Swiss in Germany and Austria. Interbull Bulletin, No. 29, 111-115.
  6. Jamrozik J., Schaeffer L.R., Deckers J.C.M. (1997): Genetic evaluation of dairy cattle using test yields and random regression model. J. Dairy Sci., 80, 1217-1226. Go to original source... Go to PubMed...
  7. Jamrozik J., Schaeffer L.R., Grignola F. (1998): Genetic parameters for production traits and somatic cell score of Canadian Holsteins with multiple trait random regression model. In: Proc. 6th World Congr. Genet. Appl. Livest. Prod., Armidale, 303-306.
  8. Kučera J., Hyánek J., Mikšík J., Čermák V. (1999): Vliv období otelení na mléčnou užitkovost dojnic českého strakatého skotu. Czech J. Anim. Sci., 44, 343-350.
  9. Lidauer M., Mäntisaari E.A., Strandèn I., Pösö J. (2000): Multiple-trait random regression test-day model for all lactations. In: Proc. Interbull Meeting, Vienna, Austria, Int. Bull Evaluation Service, Bulletin No. 16, 75-79.
  10. Reents R., Dopp L., Reinhardt F., Schmutz M. (1998): Beschreibung des Zuchtwertschätzverfahrens für Milchleistung (Testtagstiermodell). In: Aktueller Stand und neue Entwicklungen der Zuchtwertschätzung beim Rind. DGfZ - Schriftenreihe, Heft 11, 16-33.
  11. Schaeffer L.R., Deckers J.C.M. (1994): Random regressions in animal models for test-day production in dairy cattle. In: Proc. 5th World Congr. Genet. Appl. Livest. Prod., Guelph, Canada, 443-446.
  12. Schaeffer L.R., Jamrozik J., Kistemaker G., VanDoormaal B. (2000): Experience with a test-day model. J. Dairy Sci., 83, 1135-1144. Go to original source... Go to PubMed...
  13. Strabel T., Misztal I. (1999): Genetic parameters for first and second lactation milk yields of Polish Black and White cattle with random regression test-day models. J. Dairy Sci., 82, 2805-2810. Go to original source... Go to PubMed...
  14. Strandberg E., Lundberg C. (1991): A note on the estimation of environmental effects on lactation curves, Anim. Prod., 53, 399-402. Go to original source...
  15. Swalve H.H. (2000): Theoretical basis and computational methods for different test-day genetic evaluation methods, J. Dairy Sci., 83, 1115-1124. Go to original source... Go to PubMed...
  16. Tekerli M., Akinci Z., Dogan I., Akcan A. (2000): Factors affecting the shape of lactation curves of Holstein cows from the Balikesir province of Turkey. J. Dairy Sci., 83, 1381-1386. Go to original source... Go to PubMed...
  17. Tsuruta S., Misztal I., Strandén I. (2001): Use of the preconditioned conjugate gradient algorithm as a generic solver for mixed-model equations in animal breeding applications. J. Anim. Sci., 79, 1116-1172. h p://nce. ads.uga.edu/~ignacy Go to original source... Go to PubMed...

This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY NC 4.0), which permits non-comercial use, distribution, and reproduction in any medium, provided the original publication is properly cited. No use, distribution or reproduction is permitted which does not comply with these terms.