Browsing by Author "Ravaska, Lotta"

Reproduction traits are economically important features in pig production. Inbreeding has negative effect on fitness and fertility of the animals. In pig production, the increase of inbreeding reduces litter sizes and increases piglet mortality. The aim of this study was to examine the effect of parents inbreeding to number of piglets born alive, stillbirths and weaned piglets in Finnish Landrace pig population. An additional goal was to estimate heritability of the studied traits. The data used in the thesis was received from Figen Oy including pedigree and reproduction information. R and DMU programs were used for data management and statistical analyses. The number piglets born alive and weaned piglets increased during the years 2012 and 2021. At the same time number of stillborn piglets also increased. The average inbreeding rate of the boars was 0,104 and of sows 0,102. The annual average inbreeding rate of boars and sows increased significantly in the reviewed period. Heritability of investigated traits varied between 0,05 (number of stillborn and weaned piglets in litter) and 0,10 (number of piglets born alive). The inbreeding rate of the boar had statistically significant effect on the number of piglets born alive and weaned; 10 % unit increase in inbreeding coefficient decreased piglets born alive by 0,35 and the number of weaned piglets by 0,24. A negative dependency between increased inbreeding value of sow and litter size was also found in study but these results were not statistically significant. Inbreeding of either of the parents did not have statistically significant effect on the number of stillborn piglets. In the future there should be paid more attention to the increasing level of inbreeding in the Finnish Landrace population.