A device for the atraumatic transfer of a material or substance with a reproductive, therapeutic or diagnostic purpose into a female mammal, such as a bovine, allowing a transfer into a region, so-called transfer region, of an uterine horn of a female mammal, the device comprising: - a body assembly; - an outer sheath having an open proximal end and an open distal end, the outer sheath being integral with the body assembly and able to be inserted into the vagina of the female mammal and to pass the uterine cervix of the female mammal; - an inner sheath having an open proximal end, a distal end in which at least one opening, so-called transfer opening, is provided, and an inner channel extending between the proximal and distal ends of the inner sheath and able to receive a material, or a substance, with a reproductive, therapeutic or diagnostic purpose to be transferred, the inner sheath being slidably received inside the outer sheath and being flexible so as to be able to be extended, from the distal end of the outer sheath, into the uterine horn of the female mammal until the distal end of the inner sheath is located in the transfer region; and - a plunger (5; 5') intended, after placing inside the inner sheath the material or substance to be transferred, to be inserted into the inner sheath so as to be able to slide therein and to move, by a relative translation movement between the plunger (5; 5') and the inner sheath, the material or substance to be transferred towards the distal end of the inner sheath, through which the material or substance to be transferred will be placed in the transfer region, the device being characterised in that a part, so-called distal part, of the plunger (5; 5') is flexible and able to be extended into the part, so-called distal part, of the inner sheath which is intended to be extended into the uterine horn, and in that the device comprises joint movement means for jointly moving the inner sheath and the plunger (5; 5') to the transfer region, with said distal part of the plunger (5; 5') located inside said distal part of the inner sheath, and retraction means for retracting the inner sheath on the plunger (5; 5') at the transfer region, so as to force out the material or substance to be transferred through the distal end of the inner sheath, under the push of the plunger (5; 5'). - a body assembly; - an outer sheath having an open proximal end and an open distal end, the outer sheath being integral with the body assembly and able to be inserted into the vagina of the female mammal and to pass the uterine cervix of the female mammal; - an inner sheath having an open proximal end, a distal end in which at least one opening, so-called transfer opening, is provided, and an inner channel extending between the proximal and distal ends of the inner sheath and able to receive a material, or a substance, with a reproductive, therapeutic or diagnostic purpose to be transferred, the inner sheath being slidably received inside the outer sheath and being flexible so as to be able to be extended, from the distal end of the outer sheath, into the uterine horn of the female mammal until the distal end of the inner sheath is located in the transfer region; and - a plunger (5; 5') intended, after placing inside the inner sheath the material or substance to be transferred, to be inserted into the inner sheath so as to be able to slide therein and to move, by a relative translation movement between the plunger (5; 5') and the inner sheath, the material or substance to be transferred towards the distal end of the inner sheath, through which the material or substance to be transferred will be placed in the transfer region,