Foetal testicular steroidogenesis and responsiveness to LH in freemartins and their male co-twins.
Foetal gonads were obtained from 1) 8 male foetuses that were co-twin to freemartins, 2) 8 isosexual twins, 3) 59 singletons of 45-75 days of gestations, 4) 5 isosexual and 5 male co-twins of 90-120 days and 5) 5 freemartins at 70-120 days of gestation. The gonads were incubated in supplemented medium 199 for 24 h in the absence or presence or LH and the testosterone and progesterone produced measured by RIA. During the time of sexual differentiation (45-75 days) the testes of the male co-twins produced significantly less testosterone than testes from isosexual or singletons of the same age. Testes of foetuses older than 90 days were refractory to LH-stimulation, but freemartin ovaries and testes from their male co-twins continued to respond to LH with increased testosterone production. No significant differences in progesterone production were detected amount co-twins, isosexual twins or singletons at any age. We conclude that the testes of the male twin that is co-twin to a freemartin displays abnormal steroidogenesis. This may be related to reports of abnormal testes after birth in males co-twin to freemartins.
D000818:Animals; D002417:Cattle; D005260:Female; D007986:Luteinizing Hormone / Q000494:pharmacology*; D008297:Male; D010053:Ovary / Q000378:metabolism; D011247:Pregnancy; D011374:Progesterone / Q000096:biosynthesis*; D013737:Testis / Q000187:drug effects / Q000196:embryology* / Q000378:metabolism; D013739:Testosterone / Q000096:biosynthesis*; D014427:Twins
D013739:Testosterone; D011374:Progesterone; D007986:Luteinizing Hormone