Summary The ovine major histocompatibility complex (MhcOvar) class II region was investigated by Southern blot hybridizations using ovine probes specific for the second exons of Ovar‐DRB and Ovar‐DQB genes. Multiple bands were revealed when genomic DNA was digested with each of five restriction enzymes (Bam HI, Eco RI, Hin dIII, PvuII and TaqI), and successively hybridized with the two radiolabeled ovine probes. Restriction fragment length polymorphisms (RFLPs) were analysed in 89 sheep originating from six inbred families and the inheritance of the fragment patterns was determined. Forty‐one fragments were recorded with the DQB probe; 32 were detected with the DRB probe. They constituted 9 DQB and 10 DRB allelic patterns. Twelve DQB‐DRB haplotypes were resolved in this study.

300 S!edish Red-White heifers have been imported without having asked for any guarantee of their normal karyotypes. 1 6 of them — having a i /2 9 carrier maternal grandfatherwere evaluated. 3 cows and one calf born in Hungary were found as heterozygous for the 1 / 29 centric fusion. Planches descriptives des chromosomes du cheval