Five new cases of reciprocal translocation in the domestic pig are described. Three of them, rep(3;5)(p1.3;q2.3), rep(6;13)(p1.5;q4.1) and rep(13;17)(q4.1;q1.1) were found in boars with decreased litter size. The remaining two were identified in animals karyotyped before reproduction: a young boar, rep(4;6)(q2.1;q2.8), and a gilt, rep(2;14)(q1.3;q2.7). A parental origin by inheritance of the translocations was established in cases 1, 4, and 5. A decrease in prolificacy of 43% and 34% was estimated in cases 1 and 3, respectively.