Selection of clones for porcine skeletal muscle cDNA microarray assembly by colony hybridisation. A. A typical colony dot-blot hybridisation result of randomly selected plasmid clones, from a 50-day-old foetal back muscle cDNA library, probed with 32P-labelled total cDNA, derived from the same muscle of a 50-day-old foetus. B. A typical hybridisation result of selected plasmid clones, assessed by previous hybridisation (A) to be from weakly to moderately expressed genes. A reduction in the number of highly expressed clones could be seen in panel B.