Volume 3, Issue 6 (3-2013)                   rap 2013, 3(6): 35-45 | Back to browse issues page

XML Persian Abstract Print


Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Mohammadi H, Moradi Shahrebabak M, Moradi Shahrebabak H. Estimation of Phenotypic and Genetic Parameters for Ewe Reproductive Traits in Shal Sheep. rap. 2013; 3 (6) :35-45
URL: http://rap.sanru.ac.ir/article-1-121-en.html
University of Tabriz
Abstract:   (4176 Views)

    Data used in this study related to reproductive traits in Shal sheep that were collected during 1998 to 2009 by Agricultural Jahad organization of Qazvin province. Reproductive performances studied in this research were analyzed via main and composite traits.  The main traits were conception rate, number of lambs born and number of lambs at weaning. The composite traits were total litter weight at birth, total litter weight at weaning, total litter weight at birth per ewe exposed and total litter weight at weaning per ewe exposed. The data were analysed with restricted maximum likelihood procedure by the use of ASREML software. The effect of environmental factors such as mating year and age of ewe at mating were significant (P >0.05­) on all of reproductive traits. Estimates of heritability for animal genetic effects were mainly small and ranged from 0.06 to 0.13. The low level of heritability may be due to the typical high influence of environmental factors on reproductive traits and non-normal distributions of some traits. Estimates of repeatabilities for animal permanent environmental effects were small to medium 0.10 to 0.19. Genetic and phenotypic correlations among conception rate with number of lambs born, number of lambs at weaning, total litter weight at birth, total litter weight at weaning are negative but other genetic and phenotypic correlations among traits are positive estimated. The results suggested that selection based on TLWW could be more effective than the other traits for improvement of reproductive performance in Shal ewes.
 
Full-Text [PDF 449 kb]   (2594 Downloads)    
Type of Study: Research | Subject: Special
Received: 2013/04/7 | Revised: 2019/02/20 | Accepted: 2013/04/10 | Published: 2013/04/10

Add your comments about this article : Your username or Email:
CAPTCHA

© 2019 All Rights Reserved | Research On Animal Production(Scientific and Research)

Designed & Developed by : Yektaweb