Across‐country genetic evaluation of meat sheep from Ireland and the United Kingdom

Abstract

Genetic evaluations in sheep have proven to be an effective way of increasing farm profitability. Much research has previously been conducted on producing within‐country genetic evaluations; however, to date, no across‐country sheep genetic evaluations have been produced between Ireland and the UK. The objective of the present study was to examine the feasibility of an across‐country genetic evaluation of live body weight and carcass composition traits for Texel sheep raised in Ireland and the UK. The benefit of genetic selection based on across‐country genetic evaluations, in comparison with within‐country genetic evaluations, was also quantified. Animal traits included early‐life and postweaning live body weights, and muscle and fat depth ultrasound measurements. Irish and UK data were combined, common animals with progeny with records in both countries were identified and a series of bivariate analyses were performed separately for each trait to produce across‐country genetic evaluations. Fixed effects included contemporary group, age at first lambing of the dam, parity of the dam (Ireland), dam age at lamb's birth (UK), a gender by age of the lamb interaction, a birth type by rearing type of the lamb interaction and country of birth of the lamb. Random effects included the animal additive genetic, dam maternal, litter common environment and residual effect. The model for postweaning weight, muscle depth and fat depth included only the animal additive genetic and litter common environmental random effects. Genetic correlations between the two countries ranged from 0.82 to 0.88 for the various traits. Across‐country breeding values were estimated for all animals and response to selection was predicted using the top 10 and top 20 sires in both within‐ and across‐country analyses for the two countries. Overall, results showed that rates of genetic gain could potentially increase from between 2.59% and 19.63% from selection based on across‐country genetic evaluations compared to within‐country evaluations alone. Across‐country evaluations are feasible and would be of significant benefit to both the Irish and UK sheep industries. In order to realize these potential gains though, there would need to be a switch in emphasis by sheep breeders towards using objective traits as their primary selection criteria.

Effect of mineral-phytobiotic supplement on mass growth and meat productivity of crossbred sheep

“…У більшості країн, які займаються розведенням овець, прибуток від її реалізації складає більш ніж 90 %, а від вовни лише близько 10 %. Саме за таким критерієм розвивається вівчарство у передових за цією галуззю країнах, зокрема Австралії і Новій Зеландії та сусідніх з Україною державах Словаччині, Чехії і Польщі (Bain et al, 2008;Cloete et al, 2012;Gökdal et al, 2012;Yang et al, 2014;Brito et al, 2017;Gurgeira et al, 2022;Fitzmaurice et al, 2022).…”

Effect of a mineral-phytobiotic supplement on meat productivity and meat quality of crossbred sheep

“…In addition, consumers generally prefer to buy lean meat with low-fat content. To meet these requirements, an economic growth index has been used in sheep breeding programs in Great Britain, but its implementation has been slow (Fitzmaurice et al, 2022) Currently, the marker protein myostin, which is known as a growth and differentiation factor and belongs to the transforming superfamily, is used in breeding. Growth factor β plays a crucial role in regulating embryonic development and maintaining tissue homeostasis in adult animals (Hadjipavlou et al, 2006;Piaggio et al, 2018;Zhao & Zhang, 2019).…”

Relative contribution of Imprinting, X chromosome and Litter effects to phenotypic variation in economic traits of sheep

“…Moreover, there is a maternal component that has been often neglected when estimating variance components and heritability for different types of traits in sheep (Mokhtari et al, 2010; Singh et al, 2016; Vatankhah et al, 2016; Salemi et al, 2017; Maraveni et al, 2018; Ghafouri‐Kesbi & Abbasi, 2019; Noorian et al, 2020; Jafaroghli et al, 2021). This component is commonly referred as “litter” (Hagger, 1998), “maternal common environmental” (Fitzmaurice et al, 2022) or “maternal temporary environmental” (Everett‐Hincks et al, 2014). The litter effect refers to the fact that lambs from the same litter are phenotypically more similar than lambs from different litters.…”