Genetic diversity and breed comparison of carcass traits in Tasmanian Corriedale and East-Friesian sheep by RAPD markers

Abstract

RAPD marker assays are based on polymerase chain reaction amplification of random segments of the DNA with an identical pair of primers 8-10 bp in length consisting of arbitrary nucleotide sequence. Genetic variation and divergence within and between breeds of interest are assessed by the presence or absence of each product which is dictated by the DNA sequence at each locus. The power to detect polymorphisms is very high given that 5-20 bands can be produced using a given primer pair and multiple sets of random primers can be used to scan the entire genome for differential RAPD bands. RAPD has several advantages over other molecular markers because it can be used with uncharacterised genomes without prior knowledge of nucleotide sequence information and can be applied to problems in which only small quantities of DNA are available. It is also efficient and inexpensive.At the same slaughter weight and body condition score, Corriedales had significantly (P<0.01) higher fat score, thicker subcutaneous fat (29.6 vs 23.3 mm) and wider eye muscle (49.8 vs 36.2 mm) than East Friesians. On the other hand, East Friesians had significantly (P<0.01) heavier hot carcass weight (23.8 vs 22.3 kg), larger eye muscle area (42.9 vs 39.5 cm2) and longer eye muscle (67.1 vs 65.6 mm) than Corriedales, while shortloin length (SLL) in the two breeds did not significantly differ (P>0.09).