Genetic Parameters for Body Weight and Laying Traits in Mazandaran Native Breeder Hens
Heritability, environmentaland genetic correlations between body weight at hatch (BW0), eight (BW8) and twelve (BW12) weeksof age, body weight at sexual maturity (BWM), age at sexual maturity (AFE),the weight of the first egg laid by the hen (EWM), the mean egg weight from 28 to 32 wks (EW28-32) and egg numbers (ENs) were estimated by the restricted maximum likelihood method under an animal model. Data were from six generations (generation ten to fifteen) of hens kept at the Mazandaran Breeding Center of Iran. Heritability estimates for BW0, BW8, BW12, BWM, AFE, EWM, EW28-32 and ENs were 0.134, 0.235, 0.296, 0.247, 0.344, 0.125, 0.240 and 0.156, respectively. Genetic correlations between pairs of body weight measures were moderate with a range from 0.17 to 0.43. Generally, correlations of body weight traits with AFE were weak. Genetic correlation between BW8 and AFE was low, but favorable (-0.17). Egg numbers has unfavorable genetic correlation with BWM (-0.47). However, egg weight traits had favorable genetic correlation with body weight traits, except BW0, which was almost equal to zero. Age at first egg had negative genetic correlation with egg numbers, but positive correlations with egg weight traits. The absolute value of environmental correlations between traits varied from 0.00 to 0.39. The strongest environmental correlation was found between AFE and EWM. There was moderate and positive environmental correlation between BW8 and BW12as well asbetween BW12 and BWM. The results showed that there are considerable genetic variations in important traits of Mazandaran native hens, and that selection on BW8, ENs and EWM, which are the most economicallyimportant traits in this breed, could be effective.
heritability, environmentaland genetic correlations between body weight at hatch (bw0), eight (bw8) and twelve (bw12) weeksof age, body weight at sexual maturity (bwm), age at sexual maturity (afe),the weight of the first egg laid by the hen (ewm), the mean egg weight from 28 to 32 wks (ew28-32) and egg numbers (ens) were estimated by the restricted maximum likelihood method under an animal mod...متن کامل
For estimating genetic parameters for body weight traits in Kourdi sheep data were collected from 1996 to 2013 in Kourdi Breeding Station in Northern Khorasan province of Iran. Studied traits were birth weight (BW), weaning weight (WW), six-month weight (6MW), nine-month weight (9MW) and yearling weight (YW). The fixed effects in the model were lambing year, sex, type of birth and age of dam. (...متن کامل
Genetic parameters for birth weight (BW), weaning weight (WW), 6 months weight (6MW), 9 months weight (9MW) and yearling weight (YW) in Baluchi sheep were estimated using data collected during a 26-year period (1984-2010). Estimates of (co)variance components were obtained by REML procedures by fitting a linear mixed animal model. Significant random effects for each trait were explored by fitti...متن کامل
The egg quality is one of the most important economic factors for layers that are crucial for hatchability and marketing. Given the low number of egg quality traits records, one of the approaches in estimating phenotypic and genetic parameters is multi trait analysis. The aim of this study was to estimate the phenotypic and genetic parameters of west Azerbaijan native hens egg quality traits by...متن کامل
The aim of the study was to analyze the pattern of oviposition time in laying sequences in broiler breeder hens and to determine a relationship between egg position in the sequence and egg quality. The sequences were described using mean oviposition time (hour) within a sequence, mean lag of oviposition time between successive ovipositions, and mean and cumulative lag of oviposition for a seque...متن کامل
The main aim of this research was to estimate the genetic and phenotypic parameters for productive and reproductive traits of Esfahan native chickens. Traits included body weights at hatch (BW1), 8 weeks of age (BW8), 12 weeks of age (BW12), and at sexual maturity (WSM)], age at sex maturity (ASM), egg number (EN), average egg weight (AEW) in the first 12 weeks of production, and egg production...متن کامل
دوره 2 شماره 3
صفحات 251- 256
تاریخ انتشار 2012-09-01
با دنبال کردن یک ژورنال هنگامی که شماره جدید این ژورنال منتشر می شود به شما از طریق ایمیل اطلاع داده می شود.