Detection of origin between two bloodlines of Romosinuano cattle using microsatellite screening 255

Two primary bloodlines of Romosinuano cattle exist [a Costa Rican (COR) and a Colombian (COL) bloodline] and have been imported for evaluation at the SubTropical Agricultural Research Station (STARS) near Brooksville, Florida, U.S.A. Individuals from the two bloodlines are phenotypically indistinguishable from each other. The objectives of this study were to determine: (1) the presence of detectable genetic variation between the two bloodlines; and, if so, (2) the level of accuracy with which an individual's bloodline of origin could be determined based on genetic markers. Forty-six individuals from each bloodline were screened across 50 microsatellite loci selected by proximity to published quantitative trait loci (QTL), usefulness in previously published genetic distance studies, or chromosomal location maximizing genomic coverage. Unique alleles (n = 67, COR and n = 50, COL) were detected in 46 of the microsatellite systems. Polymorphism information content values (both maximum and average) and average heterozygosities for the 50 systems were: COR, 0.891, 0.752, 0.571; and COL, 0.918, 0.705, 0.579, respectively. The informative nature of these genetic markers facilitated the correct bloodline assignments.