Paper Information

Journal:   IRANIAN JOURNAL OF AGRICULTURAL SCIENCES (JOURNAL OF AGRICULTURE)   2006 , Volume 37 , Number 1; Page(s) 73 To 82.
 
Paper: 

ESTIMATES OF (CO) VARIANCE COMPONENTS AND GENETIC PARAMETERS FOR TOTAL WEIGHT OF LAMBS WEANED PER EWE JOINED IN LORI-BAKHTIARI BREED

 
 
Author(s):  GHOLAM HOSSEINI K., VAEZ TORSHIZI R.*, VATANKHAH M.
 
* FACULTY OF AGRICULTURE, UNIVERSITY OF TARBIAT MODARRES
 
Abstract: 

Data on weaning weight of 4179 lambs born from 1005 ewes and 225 rams of Lori-Bakhtiari breed, collected during 1999 and 2003 by the Lori-Bakhtiari sheep breeding station, located in Chaharmahal-o-Bakhtiari province, were employed to estimate (co)variance components and genetic parameters for total weight of lambs weaned per ewe joined in the first, 2nd, 3rd, 4th and 5th parities. Estimates were carried out through Restricted Maximum Likelihood procedures, using univariate, repeated-records, and multivariate Animal Models. The mean total weight of lambs weaned per ewe joined in the first, 2nd, 3rd, 4th and 5th parities were 28.95±5.70, 30.86±6.99, 31.89±8.41, 32.29±8.78 and 32.36±8.01Kg, respectively. In univariate analysis, two different animal models were fitted to investigate direct additive genetic and service sire effects. Based on this analysis, direct heritability for total weight of lambs weaned per ewe joined varied from 0.090 (3rd parity) to 0.182 (4th parity). The corresponding estimates for service sire effect were very low and close to zero. Estimates of heritability and repeatability from repeated-record analysis were 0.104 and 0.332, respectively. Additive genetic correlations between different parities of total weight of lambs weaned per ewe joined were positive, ranging from 0.359 (between first and 5th parity) to 0.844 (between 4th and 5th parity). The corresponding estimates for phenotypic correlations ranged from 0.300 (between 2nd and 5th parity) to 0.667 (between 4th and 5th parity).

 
Keyword(s): GENETIC PARAMETERS, TOTAL WEIGHT OF LAMBS WEANED PER EWE JOINED, ANIMAL MODEL, REML, LORI-BAKHTIARI SHEEP
 
References: 
  • ندارد
 
  Persian Abstract Yearly Visit 54
 
Latest on Blog
Enter SID Blog