Abstract

The objective of this work was to investigate the effect of an increased Ca supply on mineral balance and bone metabolism of pregnant dairy sheep and goats in the
peripartal period.
12 goats and 10 milk sheep were divided into an experimental and a control group.
Until birth calcium carbonate (Ca: 2,5 times the daily recommended) was added to the concentrated of the experimental group. Blood, urine, faeces and colon biopsies were taken and the bone mineral density (BMD) and the bone mineral content (BMC) were measured regularly during the last month of pregnancy and until 8 weeks post
partum (pp.) The total and ionized Ca-concentrations declined in all groups at birth and returned to
normal values during the first week of lactation. Bone resorption markers (ICTP, CTX) of the sheep and goats increased before birth until the 4. day pp., remained at
this level for one week and decreased again. BMD and BMC decreased from the first week ante partum to birth. One week pp. the values increased again. 1 – 2 weeks pp.
the colon biopsies revealed higher number of vitamin D receptors as well as before and at birth. Very few significant differences in parameters in the experimental and the control group were noticed. The concentration of Ca in showed a lower effect than expected on Ca metabolism in
all animals measured in this study.