From the NMC newsletter "Udder Topics", June 1997

Many variations in milking frequency and inter-milking intervals have been tried over the past few decades. Usually these have been for social, production management or economic reasons. As milk production per cow and herd averages have increased, the interest in milking frequency has also increased. Summary points from a paper on milking frequency presented at this year's Western Dairy Management Conference follow: 

• Once-a-day or skipping milking is not accepted with high production dairy cows under intensified dairy systems.

• Twice-a-day milking with 10-14 and 12-12 intervals are acceptable with very little research information as to the benefit of the 12-12 interval.

• Three-times-a-day milking will increase milk production 10-18% over 2x. Reproductive efficiency will be slightly lower, and udder health may be improved.

• Four-times-a-day milking will increase milk production 8-12% over 3x. Udder health will be improved, with no data available on reproductive efficiency.

• When changing from 3x to 2x or 4x to 3x, dairy farm managers should not expect to see a 8-15% decrease in milk production. Research has shown that after 20 and 14 weeks of an increased frequency of milking there is a carry-over effect of 9-11%, which is the effect of lactation persistency.

• Superior facilities and management are necessary to receive the highest percentage increase from either 3x or 4x milking frequency.

• Daily milking and feeding schedules should stay the same each day. Do not milk 3x or 4x with more cows than the milking parlor and labor can handle in a 24-hour period.

• Financial benefits of milking frequency greater than 2x will be affected by feed cost, milk price, and labor cost.

Source: 3rd Western Dairy Management Conference Proceedings (1997), pg. 79