hamide nuri sadegh; ali maghsoudi; mohammad rokoei; Hadi Faraji Arogh; mehdi jahantigh
Volume 24, Issue 1 , April 2022, , Pages 13-21
Abstract
The aim of this research was to investigate the immune system responses against sheep red blood cells (SRBC) and Newcastle disease virus (NDV) in two sexes of both wild and Italian speckled quails. To compare phenotypic differences of two sexes for humoral immune responses a one-way analysis was applied, ...
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The aim of this research was to investigate the immune system responses against sheep red blood cells (SRBC) and Newcastle disease virus (NDV) in two sexes of both wild and Italian speckled quails. To compare phenotypic differences of two sexes for humoral immune responses a one-way analysis was applied, and a simple animal model using the MCMCglmm package of R software was used for genetic analysis, assuming variance components between the two sexes are different. Phenotypic comparison between males and females did not show a significant difference in any of the strains. In both strains, heritability of humoral immunity in males was higher than females. Results indicated that heritability of IgT in males (0.187), and IgY in females (0.177) were higher than other estimates in wild strain. The highest heritability was related to the NDV, which was estimated to be 0.214 and 0.268 in males and females, respectively. Therefore, genetic selection for IgN can be expected to improve the performance of the birds’ humoral immune system. Likewise, according to the higher estimates of immune responses in males, genetic selection of humoral immune responses for IgN, leads to higher genetic progression.
Hamideh Nouri Sadegh; Ali Maghsoudi; Mohammad Rokouei; Hadi Faraju-Arough; Mehdi Jahantigh
Volume 24, Issue 1 , April 2022, , Pages 13-21
Abstract
In the current research, immune system responses against sheep red blood cells (SRBC) and Newcastle disease virus (NDV) in two sexes of both wild and Italian speckled quails were investigated. To compare phenotypic differences of two sexes for humoral immune responses a one-way analysis was applied, ...
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In the current research, immune system responses against sheep red blood cells (SRBC) and Newcastle disease virus (NDV) in two sexes of both wild and Italian speckled quails were investigated. To compare phenotypic differences of two sexes for humoral immune responses a one-way analysis was applied, and a simple animal model using the MCMCglmm package of R software was used for genetic analysis, assuming variance components between the two sexes are different. Phenotypic comparison between males and females did not show a significant difference in any of the strains. In both strains, heritability of humoral immunity in males was higher than females. Results showed, in wild strain, heritability of IgT in males (0.187), and IgY in females (0.177) were higher than other estimates. The highest heritability was related to the NDV, which was estimated to be 0.214 and 0.268 in males and females, respectively. Therefore, genetic selection for IgN can be expected to improve the performance of the birds’ humoral immune system. Likewise, according to the higher estimates of immune responses in males, genetic selection of humoral immune responses for IgN, leads to higher genetic progression.
Rostam AbdolahiArpanahi
Volume 19, Issue 2 , August 2017, , Pages 255-264
Abstract
In order to estimate the genetic parameters for days from calving to first service (DFS) in Iranian Holstein cattle by using repeatability, multiple-trait (MT) and random regression (RR) models, 159,482 records of parities 1 to 6 collected during 1981 to 2013 and distributed over 33 large Holstein herds ...
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In order to estimate the genetic parameters for days from calving to first service (DFS) in Iranian Holstein cattle by using repeatability, multiple-trait (MT) and random regression (RR) models, 159,482 records of parities 1 to 6 collected during 1981 to 2013 and distributed over 33 large Holstein herds were used. Bayesian information criterion of MT model was lower than other models and Bayesian factor of MT model was significant compared to other models (P< 0.05). Estimates of heritability of DFS with RR model decreased from parity 1 (0.09±0.01) to parity 6 (0.03±0.01). Estimated heritability by MT model decreased from parity 1 (0.08) to parity 5 (0.04) and increased in parity 6 (0.10). The obtained heritability using repeatability model was 0.055±0.01. Genetic correlations between DFS in different parities were reduced continuously with increasing distance between parities in RR and MT models. Overall, the result of this study indicate that multiple trait model performs better than other models in estimation of genetic parameter for DFS.
shoheil mirhabibi; nasser Emam jomeh kashan; shahabodin gharahveysi
Volume 18, Issue 4 , December 2016, , Pages 671-678
Abstract
The present investigation was undertaken to study reason of culling, non genetic effects and genetic parameters of longevity with two method linear model and Weibull. A data set of information from Holstein dairy cows of Isfahan province (Iran) was used for this study. The culling date of 36340 animals ...
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The present investigation was undertaken to study reason of culling, non genetic effects and genetic parameters of longevity with two method linear model and Weibull. A data set of information from Holstein dairy cows of Isfahan province (Iran) was used for this study. The culling date of 36340 animals from 65 herds recorded in 1993-2014 was used. From 33219 culled cows in these years were 27.9 and 72.1 percent for voluntary and involuntary culling respectively. Lifespan and Length of productive life (LPL) were analyzed for longevity. Functional productive life (FPL) was estimated by adjusting LPL for first lactation milk yield relative to herd average. The mean of lifespan and length of productive life were estimated to be 954 and 1710 (days) respectively. The results with GLM procedure showed that HYS and age at the first calving had significant on length of productive life. The results with Lifereg procedure with Weibull function showed that effects of herd, year of first calving (p
Volume 18, Issue 4 , December 2016, , Pages 687-696
Abstract
This research was conducted to study genetic and phenotypic relationships between growth curve parameters in Mehraban sheep. The data set used in this study were obtained from the Agricultural Organization of Hamedan province and comprised 35414 body weight records from birth to 365 days of age during ...
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This research was conducted to study genetic and phenotypic relationships between growth curve parameters in Mehraban sheep. The data set used in this study were obtained from the Agricultural Organization of Hamedan province and comprised 35414 body weight records from birth to 365 days of age during 2001to 2011. Parameters of Brody growth model were studied which included A (asymptotic mature weight or average mature weight of animal), B (proportion of asymptotic mature weight to weight gain as a percent of mature weight) and K (growth rate until reaching to mature weight). Fixed factors affecting on growth curve parameters were identified using the GLM procedure of SAS software. The model of genetic analysis included direct genetic effect, maternal genetic effect, maternal permanent environmental effect and covariance between direct genetic and maternal genetic effects. To estimate genetic relationship between growth curve parameters, Bayesian method based on Gibbs sampling was used. Direct heritabilities for growth curve parameters of A, B and K were 0.29, 0.63 and 0.27, respectively. Direct genetic correlation between A and B was positive and high (0.58), which indicates that these traits are aligned with each other while the correlations between B and K (-0.69) and between A and K (-0.54) were negative. The results indicated that improvement of growth curve parameters of Mehraban sheep is possible in selection programs. Therefore, it is worthwhile to propose an optimum selection strategy for obtaining appropriate growth curve in Mehraban sheep through changing genetically the model parameters.