Effects of Prepartum Energy Intake and Calcium to Phosphorus Ratios on Lactation Response and Parturient Paresis

Abstract

Estimated digestible energy values of 115 and 170% of maintenance were offered 60 days prepartum to 188 mature (one or more lactations) Holstein cows in Experiment I and 170 cows in Experiment II. Forages and concentrates were group fed in controlled amounts with a mineral supplement provided ad libitum. Calcium to phosphorus ratios of 2.3:1 and 1.8:1 were calculated from feed intakes in the 115$ digestible energy (L1) and 170% digestible energy (H1) treatments, respectively, in Experiment I. In Experiment II ratios were 1.5:1 (L2) and 1.7:1 (H2) in the 115% and 170% digestible energy groups. Cows were offered 12.3 kilograms concentrates, 15.0 kilograms corn silage, and 6.4 kilograms alfalfa hay daily during early lactation in Experiment I and 11.4 kilograms concentrates, 13.6 kilograms corn silage, and 9.1 kilograms alfalfa hay in Experiment II.