Volume 14, Issue 4 (12-2023)
Res Anim Prod 2023, 14(4): 88-101 |
Back to browse issues page
Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:
Kazemiyan H, Hasani S, Samadi F, Mohammadi A. (2023). Investigating the genetic and phenotypic relationship between biometric traits, body weights and carcass traits measured by ultrasound in Kurdi sheep of North Khorasan. Res Anim Prod. 14(4), 88-101. doi:10.61186/rap.14.42.88
URL: http://rap.sanru.ac.ir/article-1-1318-en.html
URL: http://rap.sanru.ac.ir/article-1-1318-en.html
1- Animal and Poultry Breeding and Genetics, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
2- Department of Animal and Poultry Breeding and Genetics and Physiology, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
3- Animal and Poultry Breeding and Genetics, Ferdowsi University of Mashhad, Mashhad, Iran
2- Department of Animal and Poultry Breeding and Genetics and Physiology, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
3- Animal and Poultry Breeding and Genetics, Ferdowsi University of Mashhad, Mashhad, Iran
Abstract: (1671 Views)
Extended Abstract
Background: The profitability of sheep in terms of meat production largely depends on growth traits and carcass characteristics. Despite the importance of sheep meat quality, few studies have been conducted on native sheep in the country. Therefore, examining carcass characteristics, especially when the animals are still alive, is crucial. The aim of the present study was to investigate the genetic and phenotypic relationships between biometric traits, body weights, and carcass traits measured by ultrasound in Kurdi sheep of North Khorasan. Since measuring carcass traits is difficult and expensive, identifying strong genetic relationships could allow for the replacement of hard-to-measure carcass traits with easier-to-measure traits in breeding programs.
Methods: Data from 658 Kurdi sheep at the Shirvan Kurdish sheep breeding station in North Khorasan province, located in the northern area of eastern Iran (between 57 degrees east longitude and 37.4 degrees north latitude), were collected during the spring, summer, and autumn seasons of 2021. Information related to pedigree and birth weights (658 records), as well as weights at three months (652 records), six months (638 records), and nine months (419 records), were extracted from the station's records. The General Linear Models (GLM) procedure in SAS software was used to investigate fixed effects on the traits. To estimate parameters and genetic relationships between the traits, the Restricted Maximum Likelihood (REML) method was applied based on single and two-trait animal models in WOMBAT software. Multivariate regression was used to obtain prediction equations for carcass traits based on the other studied traits.
Results: Heritability estimates for subcutaneous fat thickness, as well as the area, width, and depth of the ultrasound longissimus muscle, were 0.10±0.06, 0.06±0.06, 0.10±0.03, and 0.08±0.03, respectively. A high positive genetic correlation was observed between subcutaneous fat thickness and longissimus muscle area (0.71±0.31). Ultrasound carcass traits exhibited a strong positive genetic correlation with tail traits. Additionally, high positive genetic correlations were found between ultrasound carcass traits and several morphometric traits, including height at the withers, height at the rump, heart girth, belly circumference, body diagonal length, thigh circumference, and rump depth. The model related to longissimus muscle area, which had the highest coefficient of determination (0.82), was deemed more reliable for prediction than other models.
Conclusion: The low heritability of traits measured by ultrasound technology in Kurdi sheep at the Shirvan breeding station indicates that improving these traits through individual selection may not be very effective. Therefore, alternative selection methods, such as family selection or marker-assisted selection, should be considered for trait improvement. Overall, due to the relatively high coefficient of determination, regression models can be effectively used to predict carcass traits in the Shirvan Kurdi sheep population.
Methods: Data from 658 Kurdi sheep at the Shirvan Kurdish sheep breeding station in North Khorasan province, located in the northern area of eastern Iran (between 57 degrees east longitude and 37.4 degrees north latitude), were collected during the spring, summer, and autumn seasons of 2021. Information related to pedigree and birth weights (658 records), as well as weights at three months (652 records), six months (638 records), and nine months (419 records), were extracted from the station's records. The General Linear Models (GLM) procedure in SAS software was used to investigate fixed effects on the traits. To estimate parameters and genetic relationships between the traits, the Restricted Maximum Likelihood (REML) method was applied based on single and two-trait animal models in WOMBAT software. Multivariate regression was used to obtain prediction equations for carcass traits based on the other studied traits.
Results: Heritability estimates for subcutaneous fat thickness, as well as the area, width, and depth of the ultrasound longissimus muscle, were 0.10±0.06, 0.06±0.06, 0.10±0.03, and 0.08±0.03, respectively. A high positive genetic correlation was observed between subcutaneous fat thickness and longissimus muscle area (0.71±0.31). Ultrasound carcass traits exhibited a strong positive genetic correlation with tail traits. Additionally, high positive genetic correlations were found between ultrasound carcass traits and several morphometric traits, including height at the withers, height at the rump, heart girth, belly circumference, body diagonal length, thigh circumference, and rump depth. The model related to longissimus muscle area, which had the highest coefficient of determination (0.82), was deemed more reliable for prediction than other models.
Conclusion: The low heritability of traits measured by ultrasound technology in Kurdi sheep at the Shirvan breeding station indicates that improving these traits through individual selection may not be very effective. Therefore, alternative selection methods, such as family selection or marker-assisted selection, should be considered for trait improvement. Overall, due to the relatively high coefficient of determination, regression models can be effectively used to predict carcass traits in the Shirvan Kurdi sheep population.
Keywords: Kurdi sheep, Genetic and phenotypic correlation, Carcass traits, Biometric traits, Ultrasound
Type of Study: Research |
Subject:
ژنتیک و اصلاح نژاد دام
Received: 2022/08/14 | Accepted: 2023/08/19
Received: 2022/08/14 | Accepted: 2023/08/19
Send email to the article author
| Rights and permissions | |
 |
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |
