Title Utjecaj mitogenoma na svojstva mliječnosti goveda Title (english) Impact of mitogenome on milk traits in cattle Author Vladimir Brajković Mentor Ino Čurik (mentor)Mentor Strahil Ristov (mentor)Committee member Vlatka Čubrić Čurik (član povjerenstva)Committee member Peter Dovč Committee member Gregor Gorjanc Granter University of Zagreb Defense date and country 2019-05-17, Croatia Scientific / art field, BIOTECHNICAL SCIENCES Universal decimal classificationUDC ) 636/637 - Animal husbandry and breeding. Produce of domestic animals and game Abstract Mitohondrijski genom dio je oksidativno fosforilacijskog metaboličkog puta koji je
odgovoran za proizvodnju energije u organizmu. Utjecaj nasljeđivanja mitogenoma na
proizvodna svojstva u stočarstvu rjeđe je proučavan. Tehnologijom određivanja
nukleotidnih sljedova druge generacije, određeni su nukleotidni sljedovi 109 cijelih
mitogenoma holstein pasmine goveda, koji predstavljaju 109 različitih rodova. Korištenjem
Magellan softvera omogućeno je dodjeljivanje nukleotidnih sljedova mitogenoma 2.373
jedinke i korištenje njihovih proizvodnih svojstava mlijeka (količina mlijeka, količine mliječne
masti i količine proteina) za prve tri laktacije. Kvanitativno-genetičkim modelom procijenjen
je udio ukupne varijance objašnjen utjecajem citoplazmatskog (mitohondrijskog)
nasljeđivanja (m2). m2 procijenjen je s četiri različita modela; (i) citoplazmatski model s
rodovima (CITO-MODEL); ii) haplotip model mitogenoma (HAPLO-MODEL); (iii)
aminokiselinski model s unikatnim aminokiselinskim kombinacijama haplotipova (AMINOMODEL)
i iiii) model evolucijskih haplogrupa (EVOL-MODEL). Utjecaji citoplazmatskog
(mitohondrijskog) nasljeđivanja, interakcija stado-godina-sezona teljenja, stalna okolina i
izravni aditivni genetski utjecaj uključeni su u model kao slučajni utjecaji. Dob kod prvog
teljenja definirana je kao nezavisna kontinuirana varijabla te modelirana kao linearna
regresija. Županija je definirana kao fiksni utjecaj. Procijenjeni udjeli fenotipskih varijanca
za prve tri laktacije, objašnjene s m2rod, m2hap i m2aminohap iznose od 7% do 10% za svojstvo
količine mlijeka. Za svojstvo količine mliječne masti procijenjeni udjeli fenotipskih varijanca
za prve tri laktacije, objašnjene s m2rod, m2hap i m2aminohap, iznose od 5% do 8%. Najveći
procijenjeni udjeli fenotipskih varijanca za prve tri laktacije, objašnjene s m2rod, m2hap i
m2aminohap, dobiveni su za količinu proteina te iznose od 8% do 15%. Procijenjeni udjeli
fenotipskih varijanci u CITO, HAPLO i AMINO modelu značajni su za sva tri mliječna
proizvodna svojstva. Utjecaj evolucijskih haplogrupa u procjeni komponenti varijanci
proizvodnih svojstava mlijeka nije se pokazao značajnim. Filogenetska analiza mitogenoma
holstein goveda otkrila je veliku raznolikost haplotipova unutar T3 haplogrupe koja je
specifična za većinu pasmina vrste Bos taurus na području Europe. Pripadnost manjeg
broja holstein goveda haplogrupama T2 i T5 ukazuje na moguća pretapanja krava
autohtonih pasmina s bikovima holstein goveda. Primijenjene analize i dobiveni rezultati
pokazali su značajan utjecaj varijabilnosti mitogenoma na fenotipsku varijancu proizvodnih
mliječnih svojstava. Doprinos su poznavanju genetske arhitekture svojstava mlijeka i baza
su za daljnje poboljšanje procjene uzgojnih vrijednosti goveda. Upotreba nasljeđivanja
mitogenoma u praktičnom uzgoju životinja i dalje je izazov.
Abstract (english) Mitochondrial genome is a part of the oxidative phosphorylation metabolic pathway
and is responsible for the production of energy in an organism. Still, the impact of
mitogenome inheritance on the production traits in livestock is rarely studied. Using NGS
technology, 109 complete mitogenomes of Holstein cows were sequenced, representing
109 maternal lineages. Magellan software was used to assign mitogenome sequence
information to 2.373 cows and to use their milk production records (milk yield, fat yield; and
protein yield) for the first three lactation. Quantitative genetic model was used to estimate
the proportion of total variance explained by cytoplasmatic (mitochondrial) inheritance (m2).
m2 was estimated with four different models; i) cytoplasmic model with maternal lineages
(CITO-MODEL), ii) haplotypic model with mitogenome haplotypes (HAPLO-MODEL) iii)
amino-acid model with unique amino-acid haplotype combinations (AMINO-MODEL) and
iiii) model with evolutionary haplogroups (EVOL-MODEL). Cytoplasmatic (mitochondrial)
inheritance, interaction herd-year-season, permanent environment and direct additive
genetic effect were included in model as random effects. Age at first calving was used as
covariate and was modeled as linear regression. Region (county) was included in model as
fixed class effect. The estimated proportions of the phenotypic variances for the first three
lactations, explained by m2rod, m2hap and m2aminohap were ranging from 7% to 10% for the milk
yield. For the fat yield, the estimated proportions of the phenotypic variances for the first
three lactations, explained by m2rod and m2hap, were ranging from 5% to 8%. The highest
proportions of the phenotypic variance for the first three lactations, explained by m2rod, m2hap
and m2aminohap, were for the protein yield, ranging from 8% to 15%. The estimated proportions
of phenotypic variances in the CITO, HAPLO and AMINO models were significant for all
three milk production traits. No significant component of variance attributable to the
evolution haplogroups was found for the milk production traits. The phylogenetic analysis
of Holstein mitogenomes revealed a large variety of haplotypes within the T3 haplogroup
that is specific to most Bos taurus breeds in Europe. The presence of a smaller number of
Holstein cows within haplogroups T2 and T5 indicates the possibility of crossbreeding
between autochthonous cow breeds with Holstein bulls. The performed analyses and the
obtained results showed that a considerable proportion of the phenotypic variance in milk
traits was explained by the mitogenome variation. This contributes to the knowledge of the
genetic architecture of milk production traits that are the basis for a further improvement of
breeding values in cattle. The utilization of mitogenome inheritance in practical animal
breeding remains challenging.
Keywords
proizvodna svojstva mlijeka
mitogenom
holstein govedo
komponente varijance
određivanje nukleotidnog slijeda druge generacije
filogenetika
Keywords (english)
milk production traits
mitogenome
Holstein cattle
variance components
next generation sequencing (NGS)
phylogenetics
Language croatian URN:NBN urn:nbn:hr:204:199203 Study programme Title: Agricultural Sciences Catalog URL http://161.53.95.232/cgi-bin/wero.cgi?q=580356001372 Type of resource Text File origin Born digital Access conditions Open access Terms of use Created on 2019-07-02 07:09:48
