Effects of antioxidant vitamins on newborn and placental traits in gestations at high altitude: comparative study in high and low altitude native sheep
Víctor H. Parraguez A C E , Miljenko Atlagich A , Oscar Araneda B , Carlos García B , Andrés Muñoz D , Mónica De los Reyes A and Bessie Urquieta A
+ Author Affiliations
- Author Affiliations
A Faculty of Veterinary Sciences, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile.
B Faculty of Medicine, University of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile.
C International Center for Andean Studies (INCAS), Universty of Chile, Casilla 2, Correo 15, La Granja, Santiago, Chile.
D Department of Genetics, Gregor Mendel Blg., Campus Rabanales, University of Córdoba, 14071 Córdoba, Spain.
E Corresponding author. Email: vparragu@uchile.cl
Reproduction, Fertility and Development 23(2) 285-296 https://doi.org/10.1071/RD10016
Submitted: 28 January 2010 Accepted: 2 July 2010 Published: 4 January 2011
Abstract
The present study evaluated the hypothesis that the effects of hypoxia on sheep pregnancies at high altitude (HA) are mediated by oxidative stress and that antioxidant vitamins may prevent these effects. Both HA native and newcomer ewes were maintained at an altitude of 3589 m during mating and pregnancy. Control low altitude (LA) native ewes were maintained at sea level. Half of each group received daily oral supplements of vitamins C (500 mg) and E (350 IU) during mating and gestation. Near term, maternal plasma vitamin levels and oxidative stress biomarkers were measured. At delivery, lambs were weighed and measured, and placentas were recovered for macroscopic and microscopic evaluation. Vitamin concentrations in supplemented ewes were two- or threefold greater than in non-supplemented ewes. Plasma carbonyls and malondialdehyde in non-supplemented ewes were consistent with a state of oxidative stress, which was prevented by vitamin supplementation. Vitamin supplementation increased lamb birthweight and cotyledon number in both HA native and newcomer ewes, although placental weight and cotyledon surface were diminished. Placentas from vitamin-supplemented HA ewes were similar to those from ewes at sea level, making these placental traits (weight, number and diameter of cotyledons) similar to those from ewes at sea level. Vitamin supplementation had no effect on LA pregnancies. In conclusion, supplementation with vitamins C and E during pregnancy at HA prevents oxidative stress, improving pregnancy outcomes.
Additional keywords: hypoxia, ovine, oxidative stress, pregnancy.
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