Genetic Parameters for Functional Longevity, Type Traits, and Production in the Serbian Holstein

Abstract

In this study, the authors focused on the evaluation of the genetic parameters of longevity, milk yield traits, and type traits in dairy cattle populations in the Republic of Serbia. The total dataset used consisted of production records and pedigree data for 32,512 Holstein cows that calved from 1981 to 2015. The animal model was applied to determine the variance and covariance components and genetic parameters of the analyzed traits by applying the restricted maximum likelihood (REML) approach and using the programs VCE6 and PEST. The heritability of longevity traits was estimated using the Survival Kit V6.0 software package. Variance and covariance were estimated for five production traits: milk yield (MY), fat yield (FY), protein yield (PY), milk fat content (MC), and protein content (PC), and three longevity traits: length of productive life (LPL), lifetime milk yield (LMY), and the number of lactations achieved (NL) as well as for 18 standard type traits. Heritabilities for the milk, fat, and protein yield traits were 0.20 (MY), 0.15 (FY), and 0.19 (PY), respectively. The estimated coefficients of heritability for the longevity traits were higher when using the Weibull proportional hazards model compared to the traditional linear methods and ranged from 0.08 for NL to 0.10 for LPL. Heritability values for the type traits varied from a low of 0.10 (RLSsv—rear legs set–side view) to medium values of 0.32 (ST-stature). Genetic correlations were found between MY and the following longevity traits: LPL, LMY, and NL with values of −0.18, −0.11, and −0.09, respectively. Genetic correlations were found between MY and a number of linear type traits and varied from 0.02 (between MY and RUH-rear udder height) to 0.28 (between MY and FUA-fore udder attachment). Genetic correlations between the 18 investigated type traits ranged from −0.33 between TL (top line) and RTP (rear teats position) to 0.71 between AN (angularity) and RUH (rear udder height). Genetic correlations between most linear type traits and longevity traits (LPL, LMY, and NL) were generally negative and very low. The highest positive genetic correlation was found between UD and LPL (rxy = 0.38).

Genomic characterization of Serbian Holstein-Friesian cattle population

“…Holstein-Friesian (HF) is the most numerous and important cattle breed in the Autonomous Province of Vojvodina (APV), which represents the northern part of Serbia. The original population of Holstein-Friesian cattle in Serbia was formed by importing cows and heifers from various European countries (Netherlands, Germany, Denmark, Belgium), and then from the USA, as well as by importing the semen of progeny-tested bulls (Djedovic et al 2023). HF cattle were also crossed with locally present breeds in order to improve their productivity.…”

Clustering of countries based on dairy productivity characteristics of Holstein cattle for breeding material selection

“…The structure of a particular index often depends on the purpose of breeding on a particular farm, region or country. The index used in one region does not always agree with the selection vector of another region [19][20][21][22][23][24]. For example, in Australia, Denmark, and the United Kingdom, an increase in milk productivity is used in the national indices but not in Canada, Switzerland, and Germany [25].…”

The Dynamics of First-Calf Heifers’ Exterior Traits Within Different Years of Evaluation, Age and the Season of Birth and Calving

“…Моніторинг селекційних ознак дає можливість визначення оптимальних та середніх по популяціях значень альтернативних ознак селекційного процесу (Polupan et al, 2022). В дослідженнях українських (Bashchenko et al, 2022;Hyl et al, 2019;Dankiv et al, 2020;Papakina et al, 2020;Polupan, 2013;Polupan, 2016;Stavetska et al, 2016;Fedorovych et al, 2021;Khmelnychyi et al, 2022;Kohut et al, 2022;Kuziv et al, 2021;Ladyka et al, 2021) і вчених інших країн світу (Tilki et al, 2005;Vohra et al, 2015;Worogo et al, 2021) багато уваги приділено вивченню екстер'єрноконституціональних закономірностей формування господарськи корисних ознак молочної худоби залежно від впливу генетичних чинників (Shuliar et al, 2020;Djedovi´c et al, 2023;Janković et al, 2021;Touchberry, 1951), породи (Karamfylov , 2020), походження (Karatieieva et al, 2020;Kohut, 2020;Kochuk-Yashchenko et al, 2021;Khmelnychyi et al, 2021;Traoré et al, 2016), методів розведення (Verbych et al, 2021Nascimento et al, 2023), пігментації волосяного покриву (Sliusar, 2017) тощо. Подальше вивчення закономірностей формування екстер'єру вітчизняної молочної худоби лишається і наразі актуальним, адже знання особливостей росту та розвитку організму тварин дає можливість керувати ними свідомо, спрямовувати їх у найбільш корисний для виробництва бік.…”