Effect of Feeding a Calcium Chloride Supplement on Sow Stillbirth Rate

The present study was undertaken to determine the effect of daily calcium chloride (CaCl ) supplementation from day of entry into the farrowing house until day of farrowing (6.4 ± 0.3 d) on stillbirth rates. Landrace × Large White sows (parities 4 to 6; = 53) were offered 40 g/d CaCl ( = 28) or served as controls ( = 25). The morning before their estimated farrowing date, a blood sample was obtained from 25 sows for calcium measurement and a urine sample from 22 sows for pH measurement. The feeding of CaCl decreased urinary pH compared to the control group ( < 0.001), indicative of an induced metabolic acidosis, but there was no effect of feeding CaCl on serum calcium concentrations or the incidence of stillbirths. Nonetheless, regardless of treatment, sows with higher serum calcium concentrations (>2.5 vs.