Evaluation of Risks from Environmental Contact with Transgenic Livestock - Abstract
Assessment of the risks associated with exposing non-transgenic animals to transgenic animals is important to the future contributions of transgenic livestock to livestock production and society. Evaluation of the potential for the transfer of a transgene (Tg) from livestock to a non-transgenic animal during parturition, mating, gestation, or lactation is the initial step in a risk assessment. We previously developed and characterized transgenic swine containing a mammary-specific Tg, bovine alactalbumin, (Ba-LA) that results in increased milk production in sows. In this study, we wanted to determine whether Ba-LA is expressed in tissues of transgenic swine other than the lactating mammary gland and if the Tg DNA crosses into non-transgenic swine under various physiological and physical conditions. The specific aims addressed in this study were to determine (1) whether the bovine a-lactalbumin protein can be synthesized in any other tissues than the mammary gland of a transgenic sow; (2) whether the Tg can be transferred directly by physical association or contact; (3) whether the Tg can be transferred directly via mating; and (4) whether the Tg can be transferred directly during gestation, parturition, or lactation.