Gestational dietary protein is associated with sex specific decrease in blood flow, fetal heart growth and post-natal blood pressure of progeny.
The incidence of adverse pregnancy outcomes is higher in pregnancies where the fetus is male. Sex specific differences in feto-placental perfusion indices identified by Doppler assessment have recently been associated with placental insufficiency and fetal growth restriction. This study aims to investigate sex specific differences in placental perfusion and to correlate these changes with fetal growth. It represents the largest comprehensive study under field conditions of uterine hemodynamics in a monotocous species, with a similar long gestation period to the human. Primiparous 14 mo heifers in Australia (n=360) and UK (n=180) were either individually or group fed, respectively, diets with differing protein content (18, 14, 10 or 7% crude protein (CP)) from 60 d prior to 98 days post conception (dpc). Fetuses and placentae were excised at 98 dpc (n = 48). Fetal development an median uterine artery blood flow were assessed monthly from 36 dpc until term using B-mode and Doppler ultrasonography. MUA blood flow to the male feto-placental unit increased in early pregnancy associated with increased fetal growth. Protein restriction before and shortly after conception (-60 d up to 23 dpc) increased MUA diameter and indices of velocity during late pregnancy, reduced fetal heart weight in the female fetus and increased heart rate at birth, but decreased systolic blood pressure at six months of age.


CONCLUSIONS
Sex specific differences both in feto-placental Doppler perfusion indices and response of these indices to dietary perturbations were observed. Further, maternal diet affected development of fetal cardiovascular system associated with altered fetal haemodynamics in utero, with such effects having a sex bias. The results from this study provide further insight into the gender specific circulatory differences present in the fetal period and developing cardiovascular system.
School of Veterinary and Medical Science, University of Nottingham, Sutton Bonington, United Kingdom.
Juan H
JH
Hernandez-Medrano
School of Paediatrics and Reproductive Health Robinson Institute, University of Adelaide, Adelaide, Australia.
Katrina J
KJ
Copping
South East Vets, Mt Gambier, South Australia, Australia.
Andrew
A
Hoare
School of Veterinary and Medical Science, University of Nottingham, Sutton Bonington, United Kingdom.
Wendela
W
Wapanaar
School of Paediatrics and Reproductive Health Robinson Institute, University of Adelaide, Adelaide, Australia; Department of Perinatal Medicine, The Womens and Childrens Hospital, North Adelaide, Australia.
Rosalie
R
Grivell
South Australian Health and Medical Research Institute, Adelaide, Australia.
Tim
T
Kuchel
School of Veterinary and Medical Science, University of Nottingham, Sutton Bonington, United Kingdom.
Giuliana
G
Miguel-Pacheco
The Chancellory, University of Newcastle, Newcastle, New South Wales, Australia.
I Caroline
IC
McMillen
School of Paediatrics and Reproductive Health Robinson Institute, University of Adelaide, Adelaide, Australia.
Raymond J
RJ
Rodgers
School of Veterinary and Medical Science, University of Nottingham, Sutton Bonington, United Kingdom.
Viv E A
VE
Perry
D000818:Animals; D001315:Australia; D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology*; D002417:Cattle; D002560:Cerebrovascular Circulation; D004044:Dietary Proteins / Q000008:administration & dosage*; D005260:Female; D047109:Fetal Development; D006321:Heart / Q000196:embryology* / Q000254:growth & development*; D008297:Male; D010920:Placenta / Q000098:blood supply / Q000196:embryology; D011247:Pregnancy; D012727:Sex Characteristics; D006113:United Kingdom; D055988:Uterine Artery / Q000503:physiopathology*
D004044:Dietary Proteins