WCRB2014 POSTER PRESENTATIONS (1) (335 abstracts)
1University of Nottingham, Leicestershire, UK; 2University of Adelaide, Adelaide, South Australia, Australia.
Introduction: This study investigates the effect of dietary crude protein on the cellular composition of the 98 days bovine placenta.
Materials and methods: Primiparous 14-month-old Bos. indicus cross heifers in Australia (n=350) were individually fed isocalorific high (H; 14%) or low (L; 7%) CP from day −60 prior to conception to 23 days post conception (dpc). At 23 days post-conception the two groups were further split into high or low % CP creating four treatment groups: i) high/high (HH), ii) low/high (LH), iii) high/low (HL), and iv) low/low (LL). At 98 dpc (n=4/group per sex), placentae were weighed, fixed, serial sectioned, immunostained for binucleate cells or vasculature, and analysed using systematic random sampling and ANOVA. QPCR indicated placental vascular endothelial growth factor A (VEGFA) and placental growth factor (PGF) expression.
Results and discussion: Our recent study showed no effect between sex or dietary treatments on binucleate cell proportion or number, however a number of significant differences were observed in placental vasculature (proportion and number) in both sexes and across the different protein groups. In addition, VEGFA expression was lower in male HL vs female HH (P<0.05) and male vs female pre-conceptual high (P<0.05). PGF expression was lower in male HH than female LL (P<0.05), male vs female pre-conceptual high (P<0.05) and male post-conceptual high in comparison to female post-conceptual low (P<0.05). Dietary protein influenced placental weight, vasculature, and protein expression, without affecting trophoblast binucleate cell proportions.