Performance traits in different generations of imported Danish Landrace pigs

Abstract. The number of foreign pig breeds imported to Lithuania has increased, especially Landraces. Animals imported from other countries get into different environmental conditions. Decisions about adaptation of Danish Landraces were made when analysing the changes in the data for productivity of imported pigs and their offsprings of F₁-F₆ generations born in Lithuania. The work was carried out in the years 1998–2006. Because of adaptation to new environmental conditions, litter size, litter weight of piglets at 21 days of age and survival rate percent of piglets for primaparous sows of Danish Landrace breed, born and grown in Lithuania, was improving, in comparison with imported primaparous sows. According to evaluation data analysis of the control fattening and carcass for Danish Landrace progeny born in the country, offspring of sixth generation (F₆) distinguished by the best fattening performance. However, tendency manifested, that with increasing daily gain in many cases meatiness traits of pigs are getting worse. Muscularity of F₆ Landraces was 1.7–2.9 % lower than of F₂-F₅ progeny of this breed (P<0.05–0.01). Therefore, when striving in the adaptation process to stabilise specific traits of Landrace pigs, especially fattening performance and meatiness, besides balanced feeding and making of good keeping conditions, it is also purposeful regularly to import boars (each 3–4 years) of this breed into breeding centres or to use Al stations services.