The sensitivity of the multiplex system was checked using template DNA dilution methods (Matsunaga et al., 1999) as shown in Fig. 2a (gel-image) and b-l (electropherograms). Fig. 2a shows that the bands for cat and pig appeared as a smear and it was difficult to ndetect when 0.01 ng DNA templates (lane 10) were used. These bands were so thin that they remained undetected in ectropherogram (Fig. 2k). Thus the limit of detection (LOD) for cat and pig was 0.02 ng. However, both gel-image (lane 10 in Fig. 2a) and electropherograms clearly detected dog, monkey and rat when 0.01 ng DNA from each species were used as template. Thus the LOD for dog, monkey and rat was 0.01 ng DNA.