Inbreeding affected differently on observations distribution of a growth trait in Iranian Baluchi sheep

Binabaj Fateme Bahri,Farhangfar Seyyed Homayoun,Jafari Majid 아세아·태평양축산학회 2021 Animal Bioscience Vol.34 No.4

Objective: Initial consequence of inbreeding is inbreeding depression which impairs the performance of growth, production, health, fertility and survival traits in different animal breeds and populations. The effect of inbreeding on economically important traits should be accurately estimated. The effect of inbreeding depression on growth traits in sheep has been reported in many breeds. Based on this, the main objective of the present research was to evaluate the impact of inbreeding on some growth traits of Iranian Baluchi sheep breed using quantile regression model. Methods: Pedigree and growth traits records of 13,633 Baluchi lambs born from year 1989 to 2016 were used in this research. The traits were birth weight, weaning weight, six-month weight, nine-month weight, and yearling weight. The contribution, inbreeding and co-ancestry software was used to calculate the pedigree statistics and inbreeding coefficients. To evaluate the impact of inbreeding on different quantiles of each growth trait, a series of quantile regression models were fitted using QUANTREG procedure of SAS software. Annual trend of inbreeding was also estimated fitting a simple linear regression of lamb’s inbreeding coefficient on the birth year. Results: Average inbreeding coefficient of the population was 1.63 percent. Annual increase rate of inbreeding of the flock was 0.11 percent (p<0.01). The results showed that the effect of inbreeding in different quantiles of growth traits is not similar. Also, inbreeding affected differently on growth traits, considering lambs’ sex and type of birth. Conclusion: Quantile regression revealed that inbreeding did not have similar effect on different quantiles of growth traits in Iranian Baluchi lambs indicating that at a given age and inbreeding coefficient, lambs with different sex and birth type were not equally influenced by inbreeding. Objective: Initial consequence of inbreeding is inbreeding depression which impairs the performance of growth, production, health, fertility and survival traits in different animal breeds and populations. The effect of inbreeding on economically important traits should be accurately estimated. The effect of inbreeding depression on growth traits in sheep has been reported in many breeds. Based on this, the main objective of the present research was to evaluate the impact of inbreeding on some growth traits of Iranian Baluchi sheep breed using quantile regression model.Methods: Pedigree and growth traits records of 13,633 Baluchi lambs born from year 1989 to 2016 were used in this research. The traits were birth weight, weaning weight, six-month weight, nine-month weight, and yearling weight. The contribution, inbreeding and co-ancestry software was used to calculate the pedigree statistics and inbreeding coefficients. To evaluate the impact of inbreeding on different quantiles of each growth trait, a series of quantile regression models were fitted using QUANTREG procedure of SAS software. Annual trend of inbreeding was also estimated fitting a simple linear regression of lamb’s inbreeding coefficient on the birth year.Results: Average inbreeding coefficient of the population was 1.63 percent. Annual increase rate of inbreeding of the flock was 0.11 percent (p<0.01). The results showed that the effect of inbreeding in different quantiles of growth traits is not similar. Also, inbreeding affected differently on growth traits, considering lambs’ sex and type of birth.Conclusion: Quantile regression revealed that inbreeding did not have similar effect on different quantiles of growth traits in Iranian Baluchi lambs indicating that at a given age and inbreeding coefficient, lambs with different sex and birth type were not equally influenced by inbreeding.

Application of random regression models for genetic analysis of 305-d milk yield over different lactations of Iranian Holsteins

Torshizi, Mahdi Elahi,Farhangfar, Homayoun,Mashhadi, Mojtaba Hosseinpour Asian Australasian Association of Animal Productio 2017 Animal Bioscience Vol.30 No.10

Objective: During the last decade, genetic evaluation of dairy cows using longitudinal data (test day milk yield or 305-day milk yield) using random regression method has been officially adopted in several countries. The objectives of this study were to estimate covariance functions for genetic and permanent environmental effects and to obtain genetic parameters of 305-day milk yield over seven parities. Methods: Data including 60,279 total 305-day milk yield of 17,309 Iranian Holstein dairy cows in 7 parities calved between 20 to 140 months between 2004 and 2011. Residual variances were modeled by homogeneous and step functions with 7 and 10 classes. Results: The results showed that a third order polynomial for additive genetic and permanent environmental effects plus a step function with 10 classes for the residual variance was the most adequate and parsimonious model to describe the covariance structure of the data. Heritability estimates obtained by this model varied from 0.17 to 0.28. The performance of this model was better than repeatability model. Moreover, 10 classes of residual variance produce the more accurate result than 7 classes or homogeneous residual effect. Conclusion: A quadratic Legendre polynomial for additive genetic and permanent environmental effects with 10 step function residual classes are sufficient to produce a parsimonious model that explained the change in 305-day milk yield over consecutive parities of Iranian Holstein cows.

Sensitive Angiogenesis Imaging of Orthotopic Bladder Tumors in Mice Using a Selective Magnetic Resonance Imaging Contrast Agent Containing VEGF121/rGel

Cho, Eun-Jin,Yang, Jaemoon,Mohamedali, Khalid A.,Lim, Eun-Kyung,Kim, Eun-Jung,Farhangfar, Carol J.,Suh, Jin-Suck,Haam, Seungjoo,Rosenblum, Michael G.,Huh, Yong-Min Lippincott Williams Wilkins, Inc. 2011 Vol. No.

OBJECTIVES:: To investigate the efficiency of magnetic resonance imaging (MRI) contrast agents employing vascular endothelial growth factor (VEGF121)/rGel conjugated MnFe2O4 nanocrystals for imaging of neovasculature using a bladder tumor model. MATERIALS AND METHODS:: VEGF121/rGel was conjugated to MnFe2O4 nanoparticles (MNPs). The targeting efficiency and detection capability of the VEGF121/rGel-MNPs were investigated in both KDR-deficient (253JB-V) and KDR-overexpressing (PAE/KDR) cells using MRI. The internalization of VEGF121/rGel-MNPs into cells was confirmed by electron microscopy. Their phosphorylation ability and cytotoxicity were compared with unconjugated VEGF121/rGel. The orthotopic tumor mice were established by implanting low KDR-expressing 253JB-V cells into the bladder dome. After tail-vein injection of VEGF121/rGel-MNPs, the MR signal enhancement of intratumoral vessels by VEGF121/rGel-MNPs was observed and inhibition test using VEGF121 was also conducted. Ex vivo MR imaging of tumor tissue, and a fluorescence immunostaining study was also performed. RESULTS:: The water-soluble VEGF121/rGel-MNPs (44.5 ± 1.2 nm) were stably suspended in the biologic media and exhibited a high relaxivity coefficient (423 mMs). They demonstrated sufficient targeting capability against KDR-overexpressing PAE/KDR cells, as confirmed by dose-dependent MR images and VEGF121 inhibition tests. The phosphorylation activity of KDR and cytotoxicity of VEGF121/rGel-MNPs were evaluated. VEGF121/rGel-MNPs successfully targeted the tumor and provided accurate anatomic details through (i) acquisition of clear neoangiogenic vascular distributions and (ii) obvious enhancement of the MR signal in T2*-weighted images. Immunostaining and blocking studies demonstrated the specific targeting ability of VEGF121/rGel-MNPs toward intratumoral angiogenesis. CONCLUSIONS:: Synthesized VEGF121/rGel-MNPs as targeted MR imaging contrast agents can be specifically delivered to tumors and bind to KDR-expressing angiogenic tumor vessels.