I am just going to say it right here. Milk per stall is not an appropriate measure of efficiency to use on a dairy farm. There seems to be a trend to use milk per stall this way, and I do not like it. Why not?
    For one, increasing milk per stall by increasing stocking density as in “High stocking density is a solution for more profits”, Dairy Star, 2022, 24:4, p. 1, is based on a fallacy. The fallacy is this: I added more cows to my barn. I made more money. So therefore, diluting the cost of a stall makes me more money. The problem is that you did not just dilute the fixed cost of a stall. You diluted the fixed cost of everything, including your tractors, skid loaders and the big one: the parlor. So yes, diluting fixed costs on a dairy with more milk from more cows often is a solution for more profits, and dairy farmers have known this for generations. The plant needs to be full. But, that does not mean the profit came from diluting the cost of a stall. In fact, on most farms with high stocking densities, adding cows and adding stalls will make more money than just adding cows. Isn’t it OK to look at individual costs, like the cost of a stall, in a financial analysis? Sure, of course. But, why not calculate profit based on the cost of all the tractors on the farm and then design a profit-increasing metric like milk per horsepower? Or, maybe milk per number of skid loaders? Using metrics like this lead one to try to improve in isolation, which can have negative consequences. This is particularly true with the use of milk per stall.
    There are several problems specific to using milk per stall. The first one is that most negative changes that occur following an increase in stocking density are long term not short term. This means you do not see the results right away; so yes, you made more money this year, but what about next year, or three years down the road? The Dairyland Initiative does a great job explaining this: https://thedairylandinitiative.vetmed.wisc.edu/home/housing-module/adult-cow-housing/stocking-density/.
    Negative effects include reduced lying time, increased lameness, sorting feed, decrease in milk fat and protein percentage, decreased milk production per cow, reduced rumination, decreased conception rates and pregnancy rates, elevated somatic cell counts, more manure contamination of legs and udders, reduced water consumption, less fresh air volume per cow, longer milking times and strains on other facilities on the farm. The effects of these changes are mostly not seen for some time after they happen. Furthermore, overstocking negatively affects five of the big six drivers of profitability as defined by Compeer and Zoetis: somatic cell count, milk per cow, cow death rate, pregnancy rate and herd replacement cost.
    But, maybe you did increase stocking density a while ago and made more money, and your pregnancy rate did not really drop. And, your somatic cell count did not really increase, and your milk per cow stayed about the same. So, how can this be true?
    What about your neighbor? How is your neighbor doing? Your neighbor probably gets more milk per cow, has a higher pregnancy rate and a lower somatic cell count than he did five years ago. In other words, even though you did not see big changes, you are in a poorer competitive position than you were before.
    There is also the problem of losing labor efficiency. Crowed pens means a lot more labor every time someone needs to find a cow or group of cows. Often there are two or even three people looking for cows. This is expensive.
    The real problem with milk per stall is that almost all the negative effects result from, or directly harm, animal welfare and animal well-being. Ouch. Putting more cows through the parlor every day typically does not decrease animal well-being. Having manure from more cows in that million-dollar manure pit does not decrease animal welfare. But, putting more cows in a stall does. Farmers know this. One of my associates told me she asked one of our successful dairy farmers why he did not crowd his cows more and he said, “Because it is the right thing to do.” She told me, “I wanted to hug him.” Putting more cows in a bed is not the right thing to do.
    This leads to the final reason for not using milk per stall as a measure of efficiency: public opinion. Imagine the bad press if a company running a for-profit prison started measuring the numbers of prisoners per bed. There would be a public outcry because everyone knows sleeping is a fundamental need of humans. Everyone also knows that lying down is a fundamental need of cows. The animal care agreement of the FARM program says, “I confirm my commitment to the highest standards of animal care by hereby agreeing that proper animal care is the responsibility of every individual who is around animals, including me.”
    Chasing milk per stall shows consumers we do not mean what we say. Saying one thing and doing another creates cognitive dissonance for our consumers, and they may respond by eating less dairy. Who wins here? Not cows, not dairy farmers and not consumers.
    We do not have to treat cows like people. The goal of any business, including dairies, is to make money. And yes, some compromises can be made, but they need to be made in ways that do not grossly compromise animal well-being. In fact, my observation from more than 40 years of veterinary practice is that farms that significantly compromise animal well-being tend not to stay in business while the ones that concentrate on excellent animal care tend to do very well. Milk per stall is not somewhere we should go. It should not be on anyone’s goal sheet. We can do better.
    Bennett is one of four dairy veterinarians at Northern Valley Dairy Production Medicine Center in Plainview, Minnesota. He also consults on dairy farms in other states. He and his wife, Pam, have four children. Jim can be reached at bennettnvac@gmail.com with comments or questions.