Kvantitativno genetska analiza linearno ocenjenih osobina vimena krava Holštajn frizijske rase

Abstract

Istraživanje je sprovedeno na teritoriji Autonomne Pokrajine Vojvodine, Republike Srbije (45.2609 ° S, 19.8319 ° I), u periodu od 2011. do 2015. godine. Skup podataka obezbedila je Glavna odgajivačka organizacija (GOO) za stočarstvo u AP Vojvodini, koja se nalazi na Departmanu za stočarstvo Poljoprivrednog fakulteta Univerziteta u Novom Sadu. Cilj ovog istraživanja je proceniti fenotipske i genetske trendove osobina vimena tokom perioda ispitivanja na osnovu linearne regresione analize priplodnih vrednosti i godina rođenja prvotelki od 2009. do 2013, godine, kako bi se pravovremeno i po najnižim troškovima izvršila odgovarajuća korekcija odgajivačkih programa. Da bi se postigao ovaj cilj, osobine su ocenjivane linearnom skalom od 1 do 9, od strane 24 ocenjivača u 12 regiona u Vojvodini. Godine ocenjivanja su bile od 2012. do 2015. na 10403 prvotelki holštajn-frizijske rase, koje su u prvu laktaciju ostvarivale od 2011. do 2015. Prvotelke su potomci 221 bikova-očeva iz domaćeg i stranog odgoja i vlasništvo su 1342 odgajivača, koji učestvuju u sprovođenju odgajivačkog programa za holštajn- frizijsku rasu. Osobine su procenjene u 4 sezone (zima, proleće, leto i jesen), 10 faza laktacije, sa periodom od 30 dana za svaku fazu. Formirane su 23 genetske grupe prema godinama rođenja bikova-očeva. Formirano je pet starosnih grupa (od 19 do 44 meseca) i tri grupe (I (od 75% do 87,5%), II (od 87,6% do 96,75%), III (96,75% ≥)) prema proporciji gena holštajn frizijske rase. Linearno ocenjivanje je sprovedeno za osobine vimena (veza prednjeg vimena (VPV), položaj prednjih sisa (PPS), dužina prednjih sisa (DPS), dubina vimena (DV), visina zadnjeg vimena (VZV), položaj zadnjih sisa (PZS), dužina zadnjih sisa (DZS)) i uglatost (UG). Statistička analiza izvršena je korišćenjem statističkih programa SAS, PEST i VCE6. Nakon prikupljanja podataka, istraživanje je podeljeno u nekoliko glavnih faza: Prva, ispitivanje uticaja sistemskih faktora na osobine vimena i uglatosti, kao i osobine proizvodnje mleka (prinos mleka, prionos masti i prionos proteina). Druga, analiza fenotipske i genetske korelacije između ispitivanih osobina. Treća, izračunavanje genetskih parametara kao što su heritabilitet (h2) za prinose mleka, masti i proteina, kao i za osobine vimena i uglatosti. Četvrta, procenu priplodne vrednosti (PV) za ispitivane osobine prvotelki. Peta, genetski i fenotipski trendovi za ispitivane osobine, koji su dali jasnu sliku o uspehu odgajivačkog programa, kao i koje osobine zahtevaju pravovremenu korekciju. U ovom istraživanju, prosečne vrednosti linearnih ocena osobina vimena i uglatosti pri prvom telenju holštajn-frizijskih krava odstupaju od idealnih ocena za HF koji su definisane od strane Svetske holštajn frizijske federacije (World Holstein Friesian Federation - WHFF)...

research was conducted on the territory of the province of Vojvodina, Republic of Serbia (45.2609° N, 19.8319° E), in the period from 2011 to 2015. The data set was provided by the Main Breeding Organization (GOO) for Animal Husbandry, which is located within the Department of Animal Husbandry of the Faculty of Agriculture, University of Novi Sad. The aim of this study is to assess the phenotypic and genetic trend of the udder traits and angularity, during the research time, on the basis of linear regression analysis of average estimated breeding value of animals on the birth year from 2009 to 2013. This is done in order to get the suitable correction of selection programs, at the appropriate time and at the lowest costs possible. In order to achieve this aim, Udder type traits and angularity were classified by 24 classifiers in 12 regions in Vojvodina, years of classification were from 2012 to 2015 on 10403 Holstein Friesian cows, which had the first calving from 2011 to 2015 in their first lactation, on a linear scale of 1 to 9. The cows are owned by 1342 breeders who participate in the implementation of the main breeding program for Holstein Friesian cattle, and they are daughters of 221 Holstein Friesian bulls. The traits were evaluated in four seasons (winter, spring, summer and autumn), ten stages of lactation, with an interval of 30 days for every stage, 23 genetic groups were formed according to the years of birth of bulls, five calving age groups ( from 19 to 44 months), and three groups of genetic compositions (I (from 75% to 87.5%), II (from 87,6% to 96,75%), III (96.75% ≥ )) according to the proportion of the Holstein Friesen gene. Udder traits included fore udder attachment (FUA); rear udder height (RUH); udder depth (UD); front teat placement (FTP); rear teat placement (RTP); front teat length (FTL), and rear teat length (RTL)) and for angularity (ANG). Statistical analysis was conducted with the help of the statistical program SAS, PEST and VCE6. After data collection, the study was divided into several main points: firstly, the examination of the influence of systemic factors on the udder traits and angularity, as well as characteristics of milk production (milk yield, fat yield, and protein yield). Secondly, there was the analysis of phenotypic and genetic correlation among the examined traits. Thirdly, genetic parameters were calculated, such as heritability (h2) for the yields of milk, fat, and protein, as well as for udder traits and angularity, and the breeding values (EBV) were also carried out. Fourthly, genetic and phenotypic trends for the assessed traits were determined, which gave a clear picture of the breeding program, as well as of the traits that need a timely correction. In this study, average values of linear udder traits and angularity at the first calving of Holstein-Frisian cows deviate from ideal assessments of HF which are defined by the World Holstein Friesian Federation (WHFF)...