Browsing by Subject "ayrshire"

Conservation of the genetic diversity enables population adaption to climate and production system changes and prevents harmful consequences of inbreeding. The aim of this study was to investigate the state of genetic diversity in Finnish Ayrshire and Finncattle breeds (Western, Eastern and Northern Finncattle) based on pedigree information. The data were received from FABA co-op. Average inbreeding coefficient and relationships were estimated for animals born between 1970 and 2017. Effective population sizes were estimated separately for each birth-year group. In addition, genetic contribution of the most important ancestors of the population were investigated. The Software packages RelaX2 and R-program were used to estimate the population parameters. Average inbreeding coefficient had either stayed at the same level or decreased for all breeds except Western Finncattle. Average inbreeding coefficient of Western Finncattle has increased 2.2 %-units during the last 20 years. In addition, average relationships between breeding animals has remained stable in other breeds except Western Finncattle. Estimated effective population sizes were 163 (AY), 78 (PSK) 74 (LSK) and 57 (ISK) for animals born between 2015 and 2017. The most important ancestors to animals born between 2015 and 2017 of each breed were A Lier (AY), Opari (LSK), Asa (ISK) and Fager (PSK). Effective population sizes of different Finncattle breeds were larger than the minimum recommendation of 50 and average relationship coefficients between breeding animals have stabilized during the past few years. Despite this, the diversity of all Finncattle breeds needs to be strictly monitored. The genetic diversity of Finnish Ayrshire is at the sustainable level that is partly due to cooperation of the Nordic breeding organizations. In the future, genomic information will hopefully provide more effective tools to estimate and manage population genetic diversity.

A goal of a livestock farmer is to get the best possible profit by rearing heifers for replacement with the lowest possible cost. On the other hand, the environment must be taken into account in production. In 2015, agriculture produced 12 per cent of Finland's greenhouse gas emissions. Breeding choices can affect production costs and the environmental impact of production. Rapid growth shortens the rearing time of slaughter animals, allowing the resources being released quickly to the following animals. A rapid growing animal will produce less emissions during its lifetime compared to a slow-growing animal. However, the weight of an adult animal should not rise because increase of weight will increase the animal's feeding costs and if the animal eats more it will produce more emissions. This study investigated the relationship between the growth of young bulls and heifers and weight of adult cows in Ayrshire breed. Research material was provided by The Finnish Animal Breeding Assocation (Faba Osk). The materials were edited and analyzed using the R software. Growth observations ranged from 16 to 24 months old bulls and from 14 to 22 months old heifers. Weight observations were from cows which were more than 600 and under 2190 days old. Variance components were analyzed using the AI-REML method. The repeatability animal model was used for predicting heritability of live weight, as several observations were available for cows. The animal model was used for predicting heritability of growth and a genetic correlation between growth and weight. Heritabilities were quite high for both characteristics; for growth 0,36 to 0,37 (standard error SE 0,018 to 0,019) and for live weight 0,43 to 0,44 (SE 0,0094 – 0,010). The repeatability of weight was 0,63. A correlation between the characteristics was 0,57 (SE 0,0296). The correlation was lower than in previous studies. Based on this research, adding growth to the total merit index would be possible. Thus, breeding of growth would be possible and it would also be economically profitable and environmentally friendly. The results can be utilized in the development of the breeding program.

Lehmä on suuren osan tuotoskaudestaan tiineenä. Tuotantokautta edeltävä vasikka vaikuttaa erityisesti alkutuotoskauden maitotuotokseen, mikäli poikimisessa on ollut vaikeuksia. Toisaalta loppulypsykauden tuotokseen vaikuttaa kohdussa kehittyvä sikiö, joka vie osan emän energiaresursseista. Tässä pro gradu -tutkielmassa on tavoitteena tutkia sikiön ja tuotoskautta edeltävän vasikan vaikutuksia emän maitotuotokseen tuotosseuranta- ja polveutumistietojen avulla. Aineisto saatiin Faba Osk:lta ja se sisälsi suomalaiset vuosina 2005–2011 syntyneet, vähintään kolmesti poikineet ayrshirelehmät sekä niiden ayrshirevasikat. Koko aineiston käsittely tehtiin R-ohjelmoinnin piirissä. Sikiön ja vasikan sukupuolen vaikutusta eri tuotoskauden vaiheissa, ja vaikutuksia maidon laatuun tutkittiin mallilla, jossa oli mukana systemaattiset kiinteät tekijät (karja, vuosi, vuodenaika ja tyhjäkauden pituus) ja lisäksi mukaan otettiin sikiön ja edeltävän vasikan sukupuolet. Edeltävän vasikan syntymäpainon ja sikiön tulevan syntymäpainon vaikutusta tutkittiin osa-aineistolla, jossa oli mukana punnitustulokset. Tämän osa-aineiston koko oli noin 12 % koko aineiston koosta. Geneettisten analyysien avulla tahdottiin tarkentaa vaikutusten esilletuloa sekä löytää mahdollinen emän maternellivaikutus sikiöstä kehittyvän vasikan syntymäpainoon ja toisaalta sikiön isän paternellivaikutus sikiön kautta lehmän maitotuotokseen. Geneettinen analysointi suoritettiin bayeslaisella MCMC-menetelmällä. Sikiön sukupuolella on pieni, mutta tilastollisesti merkitsevä vaikutus emän maitotuotokseen. Vaikutus oli havaittavissa koko tuotoskaudella ja lopputuotoskaudella, jolloin sikiö kehittyy kohdussa nopeammin. Lehmäsikiö lisäsi ensimmäisen tuotoskauden 305 päivän tuotosta 25,3 kg, toisella tuotoskaudella 25,6 kg. Edellisen vasikan sukupuolen vaikutus alkavaan tuotoskauteen oli ennakko-odotuksista poiketen päinvastainen kuin sikiöllä: sonnivasikan poikiminen paransi alkavan tuotoskauden tuotosta molemmilla tuotoskausilla, tosin vaikutusta ei havaittu ensimmäisen tuotoskauden alussa. Sonnivasikan poikiminen tuotti ensimmäisellä lypsykaudella 14,3 kg enemmän maitoa kuin lehmävasikan, toisella tuotoskaudella 55,1 kg. Maidon laatuun sikiön ja edeltävän vasikan vaikutukset olivat hyvin pieniä. Painokilon lisäys sikiön tulevaan syntymäpainoon nosti emän maitotuotosta lineaarisesti molemmilla tuotoskausilla. Edeltävän vasikan syntymäpainon kilon lisäys nosti alkavan tuotoskauden maitotuotosta kiihtyvästi. Painon vaikutuksen lisääminen analysoitavaan malliin peitti kaikissa analyyseissa sukupuolen vaikutuksen, mikä viittaa siihen, että ainakin osa sukupuolen vaikutuksesta johtuu nimenomaan sukupuoleen liittyvästä painoerosta. Sikiöstä kehittyvän vasikan syntymäpainon periytymisaste oli 0,22. Emän maternellivaikutusta ei aineistosta kyetty löytämään. Sikiön sukupuoli oli mallissa merkitsevä, ja lehmävasikan syntymäpaino oli 1,82 kg sonnivasikkaa alhaisempi. Lehmän oma geneettinen vaikutus maitotuotokseensa oli periytymisasteeltaan 0,24-0,28, sikiön isän vaikutukselle löydettiin 0,034:n periytymisaste. Sikiön isä siis vaikuttaa lehmän maitotuotokseen paternellivaikutuksen kautta ja sonnivalinnalla voidaan vaikuttaa lehmän maitotuotokseen.

Genomic selection was adopted by dairy cattle breeding industry approximately ten years ago. The aim of this study was to compare realized selection differentials and generation intervals of ayrshire and holstein cows in two selection paths, sires of cows and dams of cows in breeding programs that were based either on progeny testing or genomic selection. Progeny testing was characterized by cow calves that were born in 2008–2009 and genomic selection by calves that were born in 2015–2016. These age groups were split further into groups of first calving heifers that had calved during 2010–2011 or 2017–2018. Data for this study was received from Faba co-op and analysis of the data was performed with R-software. Selection differentials in the selection path of dams of cows increased by 1,55 NTM units in ayrshire and 1,69 NTM units in holstein breed between the age groups. Selection differentials of the dams of the first calving heifers were a bit higher than that of the dams of the cow calves. Selection differentials in the sires of cows path were 4,83 NTM units higher in ayrshire and 1,98 NTM units higher in holstein in the breeding program based on genomic selection than progeny testing. Generation interval reduced from 5,3 to 3,3 years in ayrshire and from 5,0 to 3,1 years in holstein breed. Biggest reduction in generation interval was observed in the selection path of sires of bulls, where the generation interval reduced 61 % in ayrshire and 65 % in holstein breed. Sires of cows path showed 31 % reduction in ayrshire and 32 % reduction in holstein and dams of bulls path 45 % reduction in ayrshire and 30 % reduction in holstein breed. Transfer from breeding program based on progeny testing to breeding program based on genomic selection had no influence on the generation interval of the dams of cows path. Selection differentials in the sires of cows path were higher in holstein than in ayrshire in both progeny testing and genomic selection schemes and they increased more in ayrshire breed. Selection differentials of the sires and dams of first calving heifers were a bit higher than of the dams and sires of all cow calves. As expected, genomic selection has reduced generation interval and the biggest change has occurred in sires of bulls path.

Since 2004 the Finnish Ayrshire Breeders' Society has offered a Canadian conformation classification system to its members via the cooperation with Ayrshire-Canada. The Canadian classification system differs from the Nordic system and has e.g. udder texture as a new trait describing udder softness and elasticity. The research objective was to estimate the genetic variation of udder texture and its correlation to production traits and somatic cell count and udder conformation traits in the Finnish Ayrshire cows. The data from the Finnish Ayrshire Breeders contained phenotypic records on the 1st lactation cows in 2011–2017. Finnish Animal Breeding Association (Faba osk) provided pedigree, herd, yield, insemination and calving information for the cows. The final data set for statistical analyses contained records on 3303 cows. The fixed effects of the traits were investigated by analysis of variance (R program lm). The variance and covariance components of the traits were analysed with Bayesian methodology resorting to the R program MCMCglmm. The heritabilities for the first lactation traits were 0,34 for milk yield, 0,26 for protein yield and 0,26 for fat yield and 0,10 for logarithmic somatic cell count (SCS). The heritability of udder conformation traits were from 0,13 for fore udder up to 0,47 for teat length. The heritability of udder texture was 0,15. The genetic correlation of udder texture with production traits were all negative: -0,36 – -0,34, and zero with SCS. The genetic correlations of udder texture with other udder conformations traits were positive with the highest being with mammary system (0,52), median suspensory (0,51) and udder depth (0,45). The data was representative and sufficiently large, as the heritabilities for production traits were similar to those found earlier and the accuracy of estimates was satisfactory. The longevity can be measured by the total number of lactations. The variation in this number was mainly explained by the milk yield and SCS of the first lactation records. Among the respective udder conformation traits, also the median suspensor and udder depth were significant. Because the udder texture is correlated with the latter ones, its contribution to the variation was not significant. Udder texture has a reasonable amount of genetic variation and is positively genetically correlated with other udder conformation traits, in particular with mammary system, median suspensory and udder depth. The use of the udder texture as an indicator trait for longevity would require a larger data volume. People who use the Finnish Ayrshire Breeder's AF-class-system should have all their cows assessed so the research and selection would have access to records covering a representative variation range.