VGO-0202
QUESTION
In mares the mechanism of pregnancy maintenance is attributed to the primary CL?
OPTIONS
(A) Up to 35 days
(B) Up to 150 days
(C) Full gestation
(D) None of the above
ANSWER
(A) Up to 35 days
EXPLANATION
During approximately the first 35 days of equine pregnancy, the primary corpus luteum is the principal luteal source of progesterone. Subsequent eCG secretion supports formation of accessory luteal structures, and placental progestagens later become important. Thus, the primary CL alone is the early-stage answer intended here. It may persist beyond day 35, but exclusive support until 150 days or throughout gestation does not describe the normal transition.
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Veterinary Gynaecology and Obstetrics · 240 Questions
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