Bovine Postparturient Paresis - contd.
Milk fever may be prevented with appropriate feeding during the weeks leading up to parturition. During this "dry-off" period, the cow's dietary intake of calcium should be lower than when the cow is producing milk. The resulting lower blood calcium level stimulates production of parathyroid hormone, or PTH. PTH stimulates the cow's body to quickly increase blood-calcium levels from calcium stored in the bones. However, PTH is slow to synthesize in the face of a rapid calcium decline. Essentially, lower dietary calcium during the dry-off period keeps the cow's PTH at a level that will meet any sudden calcium demand.
Another important preventive measure is dietary acidification through reduction of the dietary cation-anion difference (DCAD). Diets can be adjusted for the portion of the herd that is near parturition, using urine pH to monitor the cows' acid-base status. Prophylactic calcium treatment of cows near to or immediately after, calving may lower the incidence of milk fever in a herd. Vitamin D supplementation before calving will increase calcium absorption through the intestines, and is sometimes recommended to prevent milk fever.
