Genetic parameter estimation for pre-weaning growth traits in Jordan Awassi sheep

Vet World Vol.11 February-2018 Article-27

Research Article

Veterinary World, 11(2): 254-258

https://doi.org/10.14202/vetworld.2018.254-258

Khaleel Jawasreh¹, Zuhair Bani Ismail², Feizal Iya¹, Vielka Jeanethe Castaneda-Bustos³, and Mauricio Valencia-Posadas⁴

1. Department of Animal Production, Faculty of Agriculture, Jordan University of Science and Technology, Jordan.
2. Department of Veterinary Clinical Sciences, Faculty of Veterinary Medicine, Jordan University of Science and Technology, Jordan.
3. Department of Genetics and Biostatistics, Faculty of Veterinary Medicine and Zootechnics, National Autonomous University of Mexico, Ciudad Universitaria, CDMX 04510, Mexico.
4. Department of Veterinary and Zootechnics, Life Sciences Division, Campus Irapuato-Salamanca, University of Guanajuato, Ex Hacienda El Copal, Irapuato, Guanajuato 36500, Mexico.

Background and Aim: The aim of this study was to estimate the heritability, genetic and phenotypic correlations, and the genetic trends for pre-weaning growth traits including the birth weight (BWT), weaning weight (WWT), pre-weaning daily gain (PWDG), and weaning age (WA) in Awassi lambs.

Materials and Methods: A total of 5131 Awassi lambs from two Jordanian sheep breeding stations were used. A multitrait animal model and restricted maximum likelihood methods were used to estimate the covariances between the studied traits.

Results: The mean±standard deviation of BWT, WWT, PWDG, and WA was 4.48±0.8 kg, 17.13±0.7 kg, 0.2±0.07 g, and 65.5±0.7 days, respectively. Heritability estimates were 0.30±0.04 for BWT, 0.19±0.04 for WWT and PWDG, and 0.2±0.04 for WA. Positive genetic correlations were obtained between BWT and other traits, while negative correlations were obtained between WWT, PWDG, and WA (-0.50±0.12) and between WWT and WA (-0.67±0.14). The positive phenotypic correlation was obtained between WA and PWDG (0.63±0.01). The highest additive genetic variance was obtained for WA (34.58), while the lowest was estimated for PWDG (6.22E-04). The highest phenotypic variance was obtained for WA (175.5), while the lowest value obtained was for BWT (0.54). Maternal additive variance ranged between 0.13 and 0.03. The genetic trends were around zero for all studied traits.

Conclusion: Selection should be conducted using animals with high estimated breeding values through controlled breeding. Keywords: Awassi sheep, breeding values, growth traits, heritability.

Keywords: Awassi sheep, breeding values, growth traits, heritability.

How to cite this article: Jawasreh K, Ismail ZB, Iya F, Castaneda-Bustos VJ, Valencia- Posadas M (2018) Genetic parameter estimation for pre-weaning growth traits in Jordan Awassi sheep, Veterinary World, 11(2): 254-258.

Received: 26-09-2017 Accepted: 22-01-2018 Published online: 27-02-2018

Corresponding author: Khaleel Jawasreh E-mail: kijawasreh@just.edu.jo

DOI: 10.14202/vetworld.2018.254-258

Copyright: Jawasreh, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.