Effect of calcium chloride gel treatment in dairy cows on incidence of periparturient diseases.

Objective: To determine effect of prophylactic treatment of dairy cattle with a calcium chloride gel on serum calcium concentration in the immediate postpartum period and incidence of parturient paresis, retained fetal membranes, and displacement of the abomasum.
Design: Randomized controlled trial.
Animals: 204 Holstein cows.
Procedure: Cows were paired according to parity, whether they had previously had parturient paresis, and expected calving date. Cows in the treatment group received doses of calcium chloride gel 12 hours before expected calving, at calving, and 12 and 24 hours after calving. Cows in the control group did not receive calcium chloride gel.
Results: Compared with concentration in the control cows, mean serum calcium concentration in cows treated with calcium chloride gel was significantly increased on postcalving days 1 and 2. The increase was significant only in cows that were third parity or greater. Calcium chloride gel treatment also resulted in significantly reduced incidence of parturient paresis, parturient hypocalcemia, and displaced abomasum. The incidence of parturient paresis was lower in cows that received the precalving dose of calcium chloride gel (0/39) than in cows that did not receive the precalving dose (5/63).
Clinical Implications: Results suggest that periparturient prophylactic treatment of dairy cattle with an oral calcium chloride gel may be beneficial and that treatment would be most effective for cows of third parity or greater. Administration of a precalving dose of calcium chloride gel is necessary to reduce the incidence of parturient paresis, but postcalving treatment alone has other beneficial effects.