VGO-0005
QUESTION
Endotheliochorial placentation occurs in the?
OPTIONS
(A) Horse
(B) Dog
(C) Cow
(D) Sheep
ANSWER
(B) Dog
EXPLANATION
Dogs have an endotheliochorial placenta, in which fetal chorionic tissue lies against maternal vascular endothelium after loss of the maternal uterine epithelium and intervening connective tissue. Horses have diffuse epitheliochorial placentation. Cows and sheep have cotyledonary synepitheliochorial placentation, historically described as syndesmochorial. Neither equine nor ruminant placentation has the characteristic maternal endothelial interface of the canine placenta.
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Veterinary Gynaecology and Obstetrics · 240 Questions
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