Fig. 4.

Real-time PCR analyses on 1 μg of total RNA extracted from the pectoral muscles of layer and broiler chicks aged embryonic days (EDs) 13–18. The mRNA expressions (copy numbers) for (A) MyoD, (B) PCNA, (C) myogenin and (D) IGF-I are shown. Results are presented as means±S.E.M. (n=4 animals per strain per day); 1, 2 or 3 asterisks represent significant differences at either P<0.05, 0.01 or 0.0001, respectively, between strains on one particular sample day.