Abstract
Data set including 10860 primiparous Holstein-Friesian breed cows first calved in the period from 2011 to 2015, was used in determining phenotypic variability and correlation between the traits of milk yield and linearly estimated traits of udder and angularity. The average values obtained for type traits (angularity, fore udder attachment, front teats placement, teats length, udder depth and rear udder height) were 6.47; 5.74; 4.96; 5.20; 5.99 and 6.25, respectively. The values obtained for phenotypic correlations between linear type traits and traits of milk yield ranged from -0.042 (udder depth and milk yield) to 0.335 (fore udder attachment and protein yield). Positive phenotypic correlation (0.293) was recorded also between fore udder attachment and milk yield which is deemed the most important trait of milk yield while the lowest correlation between milk yields was determined in relation to udder depth (-0.033). The results obtained indicate a possibility of applying direct and indirect multiple traits selection which should be conducted within a national progeny-testing programme on Holstein-Friesian bulls by using the method of selection indexes.
Highlights
Modern trends in dairy industry require a permanent work on improving genotypes and phenotypes of cattle
The average values obtained for type traits were 6.47; 5.74; 4.96; 5.20; 5.99 and 6.25, respectively
The values obtained for phenotypic correlations between linear type traits and traits of milk yield ranged from -0.042 to 0.335
Summary
Modern trends in dairy industry require a permanent work on improving genotypes and phenotypes of cattle. A linear type estimation as an objective and unbiased method for estimating an animal body development has been used and it represents the basis of modern classification systems as well as the foundation of all systems for describing dairy cows (Janković, 2017). Selection of cows directed exclusively to the traits of milk yield can decrease the values of other traits which relate to a type, conformation, durability and longevity. These traits have a great economic importance, in order to increase productive life of an animal it is essential to direct selection to the traits of type which are phenotypically and genetically connected with milk yield traits. The application of selection on multiple traits can decrease unwanted cullings and increase lifetime profitability per animal (Stanojević et al, 2018)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
