Foetal development in red deer (cervus elaphus) 2. Chemical composition of the foetus and associated tissues

Abstract

ABSTRACTThe concentrations of dry matter (DM), crude protein (CP), fat and ash were determined for 18 singleton red deer foetuses of known gestational ages within the range 72 to 224 days (term = 233 days) and for their associated placentae and empty uteri. In addition, concentrations of Ca, P, Mg, Na and K were determined for the foetuses. The amniotic and allantoic fluids were analysed for DM, CP and ash content.Concentrations of all measured components in the foetal fluids increased with foetal age (except for amniotic ash concentration which decreased) and linear regressions were fitted. Concentrations in the empty uterus remained constant. Given the equations previously fitted relating the weight of these tissues t o foetal age, the weights of their chemical constituents could then be calculated at various stages.Concentrations of all measured components in the foetus increased with foetal age (except for foetal K which remained constant). In the placenta, concentrations of DM and CP tended to increase while those of fat and ash decreased. The actual weights of the chemical constituents were related to both foetal age and foetal weight by further regression analysis in the form of extended Gompertz equations.Estimates are made of the daily rates of accretion of chemical components in the foetus and adnexa and these provide data against which to assess the additional nutrient demands of pregnancy in the red deer hind.