Addiction Liability of Albino Rats: Breeding for Quantitative Differences in Morphine Drinking

Science  04 Aug 1967:
Vol. 157, Issue 3788, pp. 561-563
DOI: 10.1126/science.157.3788.561


Selective breeding produced two strains of rats that differ in their susceptibility to morphine addiction. Inbreeding the more susceptible rats in an unselected population produced susceptible offspring; inbreeding resistant rats produced resistant offspring. Further selection and inbreeding increased the strain difference in the F2 and F3 generations. The F3 generation also differed in their susceptibility to alcohol addiction.