University of Georgia researchers have found that milking three times a day has its tradeoffs.
Among the 3x herds, researchers found:
Higher rolling herd averages. In fact, in two of the years studied, the rolling herd average among 3x herds was 16 percent higher than it was among 2x herds. In the other year studied, 3x herds were 15 percent higher.
Lower somatic cell counts. Over the three-year period, somatic cell counts in 3x herds averaged 335,000, compared to 359,000 in 2x herds.
But, the 3x herds had a significantly higher percentage of cows leave the herd. During the year 2000, 37.7 percent of the animals in 3x herds exited, compared to 35.5 percent in 2x herds. In addition, milk component values were lower in the 3x herds — down 0.09 percentage points milkfat and 0.03 protein over the three-year average. And, in terms of reproductive performance, cows in 3x herds were open seven days longer than cows in 2x herds.
The findings were reported in the December 2002 Journal of Dairy Science.