Are Spotlessly Clean Stalls Really the Goal?

A few weeks ago, while looking through a dairy magazine I saw an advertisement for a freestall system showing clean stalls. The pictures in the advertisement did in fact show some very clean, almost spotless stalls. Then the other day while on a farm evaluating stalls, I was surprised to see how clean the stalls were. No manure at the back of the stalls, none tracked into the stalls, and clean bedding. Then it hit me! What was missing from those pictures in the advertisement, and from the stalls I was looking at? Cows!!

Stall use can be a good indicator of cow comfort. With an on-farm assessment of well-being, the percent of cows lying down can be accurately measured (Grant, 2019). There are three common indexes used for freestall evaluation. The Cow Comfort Index (CCI) is a very simple straight forward evaluation of the motivation to enter and lie down in the freestall. The CCI is defined as the percentage of cows that are in contact with a freestall that are lying down. So simply count the number of animals that are lying down and divide by the number of animals that are lying or standing in stalls. Well managed herds will have 85% or more of cows touching the stall lying down.

The inverse of the CCI is the Stall Standing Index (SSI). The SSI is defined as the percentage of cows that are in contact with the freestall that are standing. The goal is to have less than 15% of the cows standing that are in contact with a stall. A Stall Standing Index over 20% throughout the day has been associated with increased standing time that often contributes to lameness.

Both the CCI and the SSI can be influenced by overcrowding. When the number of stalls is limited to the cows these two indices may look better than the really are. Cows that must idlily stand waiting for a stall to become available will be more motivated to lie down quickly when one becomes available (Tucker, 2021).

The Stall Use Index (SUI) is the percentage of cows, not actively eating, that are lying down. This can more accurately reflect cow comfort in overcrowded pens. The SUI also gives insight into the number of animals that are simply idling in alleys rather than eating or resting. An SUI of greater than 75% is considered the benchmark for good cow comfort. While this method does require more cow counting to calculate, it can be very useful in pens with overcrowding.

All three of these indexes are just snapshoots in time of the stall performance and will vary throughout the day as cow activity increases and/or decreases. It is preferred to take these counts at least two hours before the next milking or one hour after cows have returned from the last milking. Also doing the observation several times during the day or over several different days can help refine the evaluation.

A University of Guelph study (Robles, 2021) found an increase in daily lying time of approximately 80 minutes per day for cows housed in barns with the cleanest stalls compared with those with the dirtiest stalls. So, cows do like clean stalls, but rather than just look at how clean the stalls are, also watch and evaluate how the cows use the stalls. In the end a clean and well-used stall is the real goal.

For more on freestall design and management refer to Penn State Extension Article "Designing and Building Dairy Cattle Freestalls."