The prefresh or close-up pen is the only pen in a dairy herd where the cow decides when she leaves. She alone determines the time of calving. This creates a potential bottleneck on the farm and results in overstocking at this critical time unless we over-build the area to alleviate stocking pressure during a calving surge.

The purpose of this calculator is to predict the required group size for the prefresh pen based on estimates of herd size, calving seasonality, age distribution and target duration of stay.

Enter the milking herd size, percent of the herd that is in the first lactation, the number of days each lactation group is in the pre-fresh pen, and the number of weeks it takes to fill the pre-fresh pen. Calculations will be done automatically. When finished you will receive the number of required pre-fresh pens and the average number of cows in the pens. You may email the results as a pdf by touching the email button. You may clear all data to begin another calculation by touching the Clear button.