Uterine oxygen uptake in the pregnant Pygmy goat.
The diffusion equilibrium method was used to measure uterine blood flow (Qut) and oxygen consumption (VutO2) of 7 Pygmy goats in the last third of pregnancy. VutO2 was 9.3 +/- 1.3 (mean +/- SEM) ml.min-1.kg-1 weight of the uterus and its contents: the placenta, fetus and fetal membranes. This O2 requirement was provided by a high blood flow (349 +/- 48 ml.min-1.kg-1) and a narrow arteriovenous difference (2.4 +/- 0.1 vol%) across the uterus. Maternal arterial O2 content (CaO2) was varied by incurring chronic anemia in 3 animals. CaO2 over the range 6.5 - 12.8 vol% did not affect uterine blood flow or the arteriovenous oxygen content difference across the uterus. Weight specific (ml.min-1.kg-1) VutO2 did not differ in animals whose total uterine weights varied over a wide range and uterine vein oxygen tension and content did not fall prior to delivery. We conclude that the absolute uterine blood flow varies over a wide range to meet the requirements of the uterine contents.
D000818:Animals; D005321:Extraembryonic Membranes / Q000033:anatomy & histology; D005260:Female; D005333:Fetus / Q000033:anatomy & histology; D006041:Goats / Q000378:metabolism*; D009929:Organ Size; D010101:Oxygen Consumption; D010920:Placenta / Q000033:anatomy & histology; D011247:Pregnancy; D011270:Pregnancy, Animal; D012039:Regional Blood Flow; D014599:Uterus / Q000033:anatomy & histology / Q000098:blood supply / Q000378:metabolism*