freemartin


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freemartin

(frē′mär′tn)
n.
A female animal, usually a calf, that is born as the twin of a male animal and is sterile because of having abnormal internal reproductive organs.

freemartin

a female twin born with a male, in which normal female sexual development has been adversely affected by hormones produced by the male twin.

freemartin

a sterile female born co-twin with a male. Occurs most commonly in cattle, very rarely in sheep, and apparently not at all in the other species. Male hormones produced by the male calf share the common circulation and inhibit the normal development of genitalia of the female. The female is also an erythrocytic chimera and can be diagnosed as a freemartin by this means. It can also be diagnosed by cytogenetic techniques. It produces white cells with XY as well as cells with XX chromosomes. Structural changes of nonpatent vagina, small vulva, cordlike uterus and hypoplastic ovaries are diagnostic but inconsistent. Some freemartins are quite normal clinically but all are sterile.
Enlarge picture
Freemartin placenta. By permission from Buergelt CD, Color Atlas of Reproductive Pathology of Domestic Animal, Mosby, 1996
References in periodicals archive ?
However, if you end up with a male/female pair, and you're a glass-half-full sort of person, there are ways to tell if your female is a heifer or a freemartin.
Touching placentas will often form into one, ensuring a freemartin.
Since a freemartin is outwardly female, about the only accurate way to determine this status when purchasing calves is an examination by a vet.
The reproductive tracts of freemartins do not develop normally.
The West Eugene club will mark the end of pre-Lenten hedonism with a party hosted by the Freemartins, Genus Pro and Papa's Soul Kitchen.