Naslov
Evaluation of genetic parameters for productive and reproductive traits in pig population in Croatia

Autori
Škorput, Dubravko

Vrsta, podvrsta i kategorija rada
Ocjenski radovi, doktorska disertacija

Fakultet
Agronomski fakultet

Mjesto
Zagreb

Datum
29.07

Godina
2013

Stranica
96

Mentor
Luković, Zoran

Ključne riječi
pigs; genetic parameters; productive and reproductive traits

Sažetak
Genetic parameters for productive and reproductive traits of gilts were estimated on 29, 323 data records for backfat thickness (BF) and time on test (TT) obtained in field test and 86, 002 data records for number of piglets born alive (NBA). Four large scale farms and group of 72 family farms were included in analysis. Residual maximum likelihood method (REML) was used to obtain (co)variance components for analyzed traits. Model with genetic groups was applied in order to account for different selection of animals for productive traits. Average reliability (r2) of breeding values was calculated with different data combinations. Three types of models were used to estimate genetic parameters for NBA: repeatability model, multiple-trait model (MT), and random regression model (RRM). Four-trait model was used for estimation of genetic parameters for productive and reproductive traits. The highest increase in r2 of 0.22 was observed in Large White when additional data were included. Heritabilities were in range from 0.12 to 0.26 for BF and 0.05 to 0.26 for TT. The range of heritabilities for NBA was from 0.00 on farm B with RRM in 1st parity to 0.24 on farm C with MT model in fourth parity. Genetic correlations between subsequent parities by repeatability and RRM were estimated to be less than 1 and NBA in different parities could be treated as different trait. Heritabilities obtained in joint genetic evaluation of productive and reproductive traits were 0.21, 0.22, 0.10 and 0.11, for BF, TT, NBA in the 1st parity and NBA in the 2nd parity. Genetic correlations between both productive traits were low, while correlations between BF and reproductive traits were low, and correlations between TT and reproductive traits were negative and moderate.

Izvorni jezik
Engleski

Znanstvena područja
Poljoprivreda (agronomija)

POVEZANOST RADA