Estimation of heritability and genetic correlations between milk yield and linear type traits in primiparous Holstein-Friesian cows

Snežana Trivunović,Vladan Bogdanović,Dragan Stanojević,Hasan Ismael,Radica Djedović,Dobrila Janković

doi:10.37496/rbz5020200121

Abstract

Estimation of genetic variability and genetic correlations between production traits (milk yield, fat yield, fat content, protein yield, and protein content) and selected type traits (angularity, fore udder height, rear udder height, front teat placement, teat length, and udder depth) was done using data sets of 10,860 first-calving Holstein-Friesian cows raised in the territory of the Republic of Serbia. Genetic variance and covariance were obtained using the Restricted Maximum Likelihood (REML) method, VCE v6 software, and the multi-trait mixed [...]

Highlights

The modern approach to dairy cattle selection has led to defining new breeding programmes whose focus of selection is shifted from milk production traits to a much more balanced approach, with the accent placed on functional traits, such as longevity and type traits (Miglior et al, 2005; Němcová et al, 2011; Tapki and Guzey, 2013)
Estimation of genetic variability and genetic correlations between production traits and selected type traits was done using data sets of 10,860 firstcalving Holstein-Friesian cows raised in the territory of the Republic of Serbia
The highest heritability values were estimated for milk production traits: milk yield (MY) (0.182), fat yield (FY) (0.134), and protein yield (PY) (0.170) (Table 4)

Summary

Introduction

The modern approach to dairy cattle selection has led to defining new breeding programmes whose focus of selection is shifted from milk production traits to a much more balanced approach, with the accent placed on functional traits, such as longevity and type traits (Miglior et al, 2005; Němcová et al, 2011; Tapki and Guzey, 2013). The new National Breeding Programme in the Republic of Serbia has set as its goal the breeding of Holstein-Friesian cows with desirable type traits, longevity, good fertility, and robustness, while retaining the existing high milk yield (Janković, 2017; Stanojević et al, 2018). The long generation interval in cattle and low heritability for fertility traits has led to increased interest in linear evaluation of type traits in cows, which can be evaluated at an early age and can indirectly influence the improvement of milk production and longevity traits. Based on the grade for each trait or linear score, animals are ranked into specific categories, and their desirability is used to select parents for the following generation

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Conclusion