Study On The Effect Of Band J In DNA Fingerprints From Different Marker Combinations

DNA fingerprinting in SR92A,Xiaoshan chickens and their offspring with EAV (endogenous avian retroviral element)as the probe is to screen genetic markers to be used in improving important traits of chickens such as alive weight,dressing weight et al.. The results show that PCR-derived EAV element is an ideal probe to be used in studies of population genetics and quantitative genetics of chickens. J band generated with EAV is indeed a good genetic marker.Results are presented of DNA fingerprint segregation analyses carried out in 4 combinations. The DNA fingerprint bands are suit to Mendelian inheritance. Comparisons of slaughter traits are studied based on presence or absence of band J in their parents. There are 4 classifications of parental matings as follows : -/- for absence of band J in both parents; -/+ for absence in sire, presence in dam; +/- for presence in sire ,absence in dam; +/+ for presence in both parents. Comparisons are made for each trait in the offspring, including alive weight ,dressing weight, semi-eviscerated weight and eviscerated weight. Alive weight ,dressing weight, semi-eviscerated weight and eviscerated weight in offsprings from -/- parental mating are 248.7g,214.8g,192.4g,167.9g higher than from +/+ parental mating. GLM procedure shows that mating combinations have a significant influence on slaughter traits of their offsprings(P<0.05 ),and there are significant difference between +/+ and -/-,-/+ matingcombination.The average effect of band J (calculated by comparing offspring of -/- parental mating type with those of+/+ parental mating type) was 118% in their offspring .The heterosis generated by -/- type is 74. 1g higher than generated by non-selected populations. So using band J as genetic marker in early and indirect selection can decrease the cost of raising ,shorten the generation interval and speed the selection progress.