Several indices have been used to assess the comfort and well-being of dairy cattle.

A successful index provides the consultant or farmer with a tool to quickly assess the comfort of stalls and the cows using the stalls in a short time frame. I will summarize the most commonly used indices, their advantages and disadvantages.

As you might guess, most indices of cow comfort have been developed for cows housed in freestall barns. But even though few indices exist to evaluate the comfort of cows in tiestalls, obviously the design and comfort of tiestalls are just as important as freestall comfort. In fact, tiestall comfort may be more important since the freedom to select a specific stall is removed from the cow in the tiestall system.

Cow Comfort Index
The Cow Comfort Index (CCI) was first described over 10 years ago and remains the most commonly used index. It is measured as the proportion of cows in contact with a stall that are actually lying down. The advantage of the CCI is that it estimates motivation to enter a freestall and lie down and is useful for both freestall and tiestall barns.

A substantial limitation is that it is not associated with mean daily lying time and is insensitive at stocking rates much above 100 percent of stalls. It remains useful as a simple index of stall comfort, but we must understand that it is not related to actual lying down time. Well managed freestall systems should have a CCI greater than 85 percent.

Stall Standing Index
The Stall Standing Index (SSI) was developed a few years ago at the University of Wisconsin in an effort to improve upon the CCI and measures the proportion of cows in contact with a stall that are standing (inverse of CCI).

Unlike the CCI, increased SSI is actually associated with increased daily standing time. Knowing when cows are spending too much time standing is important because of the strong positive relationship between standing and greater incidence of lameness. In well-managed herds, the SSI should be less than 15 to 20 percent, and an SSI greater than 20 percent is associated with standing times in excess of two hours per day and lameness problems.

Stall Use Index
The Stall Use Index (SUI) was developed by California researchers to assess the proportion of cows within a pen that are lying down divided by the cows within a pen who are not actively feeding. The SUI accurately reflects cow comfort within an overcrowded pen and reflects cows that are “wasting time” idling in alleys waiting for a stall to become available. Well-managed herds should have a SUI of greater than 75 percent.

Because the SUI is sensitive to changing stall stocking rates it should be the preferred comfort index at higher stocking rates. Really, the best assessment of overall cow comfort within a specific environment would be obtained by use of the SSI and the SUI together.

All indices of cow comfort should be measured when cows are most motivated to lie down, typically one to two hours after milking or approximately two hours before milking. Use of these simple tools does not replace more in-depth analysis of cow comfort and stall design on a dairy. But they do provide a quick and relatively accurate assessment of potential limitations in herd management that compromise cow comfort. PD

—Excerpts from William H. Miner Agricultural Research Institute Farm Report, September 2009

Rick Grant, President
William H. Miner Research Institute
grant@whminer.com