ASSESSMENT OF PARENTAL GENOMIC PROPORTIONS IN CROSSBRED CHICKENS BY DNA FINGERPRINTS

Starting with the second crossbred generation, parental genomic-propor tion lines in individuals deviate considerably from expectation. These individual variations offer the potential to increase the efficiency of crossbreeding programmes. DNA fingerprinting was established as an approach, to quantify the genomic contribution of the parental lines I n Individuals of two crossbred generations. For this purpose, specific bands were identified in representative banding patterns of pooled DN A from purebreds. The representative banding patterns obtained with ei ght combinations of restriction enzymes HinfI and AluI, and oligonucle otide probes [CA]8, [CAC]5, [GGAT]4, and [GACA]4, contained between ni ne and 14 line-specific bands. The estimation of the proportion was ba sed on the relative proportion of line-specific bands of one parental line in banding patterns of crossbreds. This was first done in F1 indi viduals with a definite 50% genomic proportion of each parental line, to determine the accuracy of the approach. The mean value, 51.0+/-0.34 % observed in 45 F1s using all eight combinations of enzymes and probe s, of genomic contribution of one parental line, was close to the theo retical value of 50%. In 24 animals of the BC1, considerable shifting of the parental genomic proportion was observed.