Hostname: page-component-745bb68f8f-s22k5 Total loading time: 0 Render date: 2025-02-11T17:17:15.974Z Has data issue: false hasContentIssue false
  • English
  • Français

Genetic analysis of lactation milk yield and age at first calving for Holstein heifers in Khorasan province of Iran

Published online by Cambridge University Press:  23 November 2017

H. Farhangfar ,
H. Naeemipour  and
P. Rowlinson
H. Farhangfar*
Affiliation:
Department of Animal Science, Birjand University, Birjand, Iran
H. Naeemipour
Affiliation:
Department of Animal Science, Birjand University, Birjand, Iran
P. Rowlinson
Affiliation:
Animal Science Department, University of Newcastle upon Tyne, Newcastle upon Tyne, U.K.
*
Email: [email protected]
Get access

Extract

The main aim of animal breeding programmes is to increase productivity and profitability of farm livestock through genetically improving the economic merit of farm livestock (Smith, 1998). This can be achieved by increasing the mean value of a population for one or several economically important traits by the genetic improvement of the animals in this population. In dairy cow husbandry, many traits of economic importance such as lactation milk yield and reproductive traits have long been of interests for breeders to increase profitability of dairy farms. Age at first calving is economically important because it determines when an animal begins its productive life and therefore could influence the lifetime productivity of an animal. Also, age at first calving can be considered as a measure of heifer fertility performance associated with reproductive efficiency. The main objective of the present research is to analyse genetic aspects of lactation milk yield and age at first calving for Holstein heifers in Khorasan province of Iran.

Type
Poster Presentations
Information
Proceedings of the British Society of Animal Science , Volume 2005 , 2005 , pp. 127
Copyright
Copyright © The British Society of Animal Science 2005

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Gilmour, A. R., Cullis, B. R., Welham, S. J. and Thompson, R. (2000) ASREML Manual. New South Wales Dep. Agric, Orange, Australia.Google Scholar
Lobo, R. N. B., Madalena, F. E. and Vieira, A. R. (2000) Average estimates of genetic parameters for beef and dairy cattle in tropical regions. Animal Breeding Abstracts 68: 433–462.Google Scholar
Smith, C. (1998) Introduction: Current Animal Breeding. In “Animal Breeding, Technology for the 21st Century”. (Clark, A. J. ed.), pp. 1–10, Harwood Academic Publishers, New Delhi, India.Google Scholar