FROM THE FARM REPORT: WHAT'S ALL THE NOISE ABOUT?

“What?” “I can’t hear you.” “Come closer.”

These were common phrases during recent on-farm tours and workshops at Miner. With warm, humid weather and barn fans running at full blast, conversations were often drowned out by the constant hum of equipment. I’ve grown so used to that background noise that I barely notice it anymore…until it became a barrier to communication. It got me thinking: how much noise is too much? And what impact does all this sound have — not just on us, but on our cattle?

Noise is defined as any unwanted, unpleasant, or loud sound. It can be constant or intermittent and is measured by its frequency or pitch (hertz; Hz) and intensity or loudness (decibels; dB). Interestingly, cattle can hear over a wider frequency range (23 to 35,000 Hz) than humans (20 to 20,000 Hz). That means they can detect sounds we can’t and those sounds may affect their well-being in ways we don’t always consider.

Noise is inevitable on-farm and comes from many sources including machinery like tractors, feed trucks, skid steers, milking equipment, ventilation equipment, electronic equipment, cattle, and people just to name a few. It all contributes to the ambient noise of a farm. To get a better sense of our own farm’s noise levels I used a free app called Sound Meter during a recent heat wave with temperatures ranging from daytime highs of 80 to 90°F with high humidity. Our calf barn with natural and tube ventilation was 70 to 73 dB, the heifer and cow barns with natural ventilation and circulation fans were 69 to 77 dB. Interestingly, the decibels didn’t change much from ~6 am readings to ~3 pm readings except for one of our cow barns with variable speed fans. The noise increased about 6 to 7 dB as the fan speed increased with rising temperatures. The loudest places in our barns were our parlor (75 to 79 dB) which was influenced by the radio volume and large mobile fan use as well as the barns when the feed truck was dispensing TMR (79 to 80 dB). The holding area with circulation fans was one of the quietest at 69 to 70 dB.

It seems that our farm is typical when compared to other farms for noise. Good farms will have ambient noise levels up to 70 or 75 db with some short periods of time where noise will exceed 75 db according to Nesli Akdeniz and John Shutske in a Wisconsin extension publication and researchers in a 2023 review article in the Acoustics journal about noise hygiene in dairy farming. To put the 70 to 75 dB in perspective, here are some common noise levels:

30 dB: quiet library, soft whisper

50 dB: quiet office, refrigerator hum

70 dB: restaurant, washing machine

90 dB: lawnmower, shouted conversations

110 dB: concerts, power tools

130 dB: jackhammer, plane takeoff

Prolonged exposure to 85+ dB can cause hearing damage in people. Thankfully, our barns generally stay below that threshold. Still, our team uses hearing protection (earmuffs or ear plugs) when operating loud machinery or tools.

Noise that is 80 to 100 dB or greater can negatively affect cattle, too. In the Acoustics article, it was noted that loud noise is a stressor for cattle and can affect their health and productivity through changes in heart rate, respiration rate, metabolism, digestion, immune function, and feeding behavior. Milk production can be decreased with just 3 hours a day of exposure to 80 to 100 dB.

Reducing the racket….so, what can we do? Here are a few simple things to reduce noise on the farm:

Maintain equipment regularly: worn out motors or dirty or poorly maintained fans are often louder

Choose quieter models: when replacing equipment, look for lower-noise options; variable speed fans can be a good option to reduce noise when less air flow is needed

Be mindful of volume: radios can contribute to the noise

— Heather Dann

dann@whminer.com