Inducing transgenics is a relatively inefficient process. According to Maclean (in press) relevant variables include the species, the workers involved and presumably also the techniques. For every hundred eggs injected, a yield of about ten percent of fish testing positive for the presence of the transgene may be expected. However, only about one percent of the eggs treated will prove ultimately to be germ line positive and capable of transmission to the next generation. This figure is in line with that found for pigs, sheep, goats and cattle (Royal Society, 2001).