Animal somatic cloning : state of the art in cattle and small ruminants

Abstract

Among the recent reproductive biotechnologies for domestic mammals, somatic cell nuclear transfer is a new step forward, since the birthof Dolly the sheep. This article reports the current results obtained worldwide in cattle, sheep and goats, the limits of the technique andsome potential applications. The overall efficiency (nb of young born/nb of reconstructed embryos) remains low (≤ 7 %), but has beenprogressing. Embryonic mortality and important foetal physiopathologies are limiting factors. A research programme on bovine clones atINRA is aimed at the evaluation of the clone’s health, their zootechnical performances as well as potential risks related to cloning. Despitesome uncontrolled biological barriers, several applications of somatic cloning are being developed such as animal models for diseases, newtools for genetic selection, reproduction of rare genotypes or association with transgenesis for biomedical use. Current research takes intoaccount the ethical aspects and societal concerns about animal cloning.