Publicación:

Síndrome de freemartin en el ganado bovino.

Resumen

The Freemartin syndrome is a state of intersexuality of many of the bovine females coming from heterosexual multiple birth (male - female). It is found in fetal life between 30 and 40 days of gestation resulting from the transplacental exchange of cells by vascular anastomosis, with phenomena of 60XX / XY chimerism occurring in several tissues, and consecutive sterility (Lopera 2015) The freemartin syndrome is not inheritable, but the propensity to breed twins is, with variable incidence among the bovine breeds (eg, Simmental from 2.4% to 4.6%, Holstein-Friesian from 0.5% to 4.2%, and Charolais From 2.5% to 3.2%). In addition, most twins are dizygotic (non-identical twins), and only 2% to 10% are monozygotic (identical twins). On the other hand, twin births are less frequent in zebu cattle breeds (Bos indicus, 0.22%) than in European-born cattle (Ayala 2012).