the data set employed in this study was comprised of a number of 6,800 records of lamb’s longevity and their survival rate, collected from 1989 through 2009, from the lori-bakhtiari experimental flock at the shooli station in shahrekord, iran. the data were analyzed using linear models and proportional hazard models with weibull function. these models included fixed factors and direct additive ...

a selection program is being implemented to improve meat production in makooei sheep. increasing litter size per ewe is the main objective, but possible repercussions on weight traits of lambs should be considered. the aim of this study was to estimate heritability along with genetic and phenotypic correlations between ewe's reproductive vs. weight traits in makooei ewes. data were comprised of...

Abstract Determination of gene effects and combining abilities is a critical stage in maize hybrid breeding. In the present study, 20 S6 lines as female and three S6 inbred lines (K18, K19 and K1264/5-1) as tester were crossed and the resulting  test cross progenies were evaluated in a randomized complete block design with three replications in 2008. During the growing period, several agronomi...

determining general and specific combining ability of lines is necessary to use them as parents of hybrid varieties. in addition, estimates of the heritability of characters helps in selecting suitable breeding methods and predicting genetic gains of the traits. to determine general and specific combining abilities and gene effects of agronomic characters, five cms lines and four restorer lines...

records of 2593 baluchi ewes, obtained from baluchi sheep breeding station in abbas abad, mashhad, were used to estimate genetic parameters for total weight of lamb weaned per ewe joined (tww/wj) in different parities. estimates of heritability for tww1/ej, tww2/ej, tww3.ej and tww4/ej were 0.112 ? 0.030, 0.028 ? 0.030, 0.075 ? 0.060 and 0.135 ? 0.120, respectively. direct additive genetic corr...

in order to estimate the genetic parameters and comparison legendre polynomials for production traits of iranian holstein dairy cattle test-day records of first lactation cows for milk yield, fat yield, protein yield, fat percentage and protein percentage traits were used. these records collected from 2006 to 2010, by the animal breeding center of iran. the genetic parameters were estimated usi...

a number of 5558 lambing records of 2245 mehraban ewes, collected during years 1995 to 2010 were utilized to estimate the variance components and heritability for the number of lambs per lambing,  making use of b-spline random regression models. the fixed factors affecting the studied trait were identified using general linear model analysis as well as sas software, where flock-year-season and ...

introduction kurdish sheep breed is one of the most important native breeds of iran. they are fat-tailed, large-sized, well adapted to the mountainous regions in northern khorasan province and mainly raising for meat production under pastoral production system (28). feed efficiency is a major component in the profitability of the small ruminant enterprise, because quality of range and pasture i...