Keywords: Guinea pig (2).jpg A guinea pig lying still being held by a technician Topics/Categories Animals Type Color Photo Source National Cancer Institute Linda Bartlett Photographer 1962 1980 Reuse Restrictions None - This image is in the public domain and can be freely reused Please credit the source and/or author listed above Linda Bartlett Photographer PD-USGov-HHS-NIH Media from National Cancer Institute Visuals Online Images uploaded by Fæ Animal testing Human hands holding cavies Experimental guinea pigs |