抄録
Growth hormone (GH) gene expression has been examined in control and transgenic coho salmon containing a transgene comprised of the sockeye salmon GH 1 gene under the control of the MT-B promoter from the same species. This transgene dramatically enhances the growth of salmonids, and raises serum GH levels some forty-fold. Transcript levels from this transgene were detected by RT-PCR in all tissues examined, and an obvious increase of the transgene expression was obtained in some developing stage. GH mRNA levels were also examined in the pituitary gland, and were found to be significantly lower (p<0.01) in transgenic compared to nontransgenic salmon of the same size. Pituitary glands of transgenic were also smaller than control of the same size. The transgenic fish changed a surface area in the anterior intestine, and the intestine of GH transgenic salmon had more folds and the path tracing the inner circumference around the intestinal folds of a cross section was about 2.7 times longer than in control salmon. Further, the transgenic salmon increased ability to compete for food, and they consumed 2.9 times more pellets that the non-transgenic controls.
