A hundred cows at the Caballero dairy munch alfalfa under the spacious barn while fans and misters keep them cool during a 79-degree spring day.
The cool digs are not just about making cows feel comfortable, especially when temperatures hit 115 or more in the summer, said dairy owner Craig Caballero. New research indicates that ambient temperature affects milk production, and for Arizona farmers that means money.
Heat stress causes about $39,000 of annual loss to the average dairy farm in the United States, according to a study published in 2014 by the U.S. Department of Agriculture. Arizona’s dairy industry production in 2013 was valued at $900 million from 200,000 milk cows, according to the U.S. National Agricultural Statistics Service.
Heat stress is a challenge dairy farms face in the hot climate of Arizona, said Mike Billotte of the United Dairymen of Arizona, a cooperative which produces 85 percent of the milk in the state. Farms are using special shade structures and cooling systems to prevent heat stress in cows.
“It is a big deal for Arizona,” Billotte said.
About 90 dairy farms are located in Arizona, with the majority based in Pinal and Maricopa counties, according to the Arizona Department of Agriculture.
Maricopa and Pinal counties tend to have high temperatures because they are lower in elevation, preventing the air to mix with the atmosphere, said Lee Carlaw, a meteorologist in the National Weather Service in Tucson. Additionally, the type of soil in the two counties is primarily sand, which absorbs the sun’s radiation and increases the temperature.
The average temperature in these two counties is around 76 degrees Fahrenheit, according to data from the National Oceanic and Atmospheric Administration Climate Normals Center.
When the cows become heat stressed, they divert more blood to the skin to dissipate heat, said Robert Collier of the College of Agriculture and Life Sciences at the University of Arizona. In turn, less blood is channeled to vital biological processes, including synthesizing milk and the cows tend to eat less food.
“You can obliterate this pattern by controlling the environment around the cow,” said Collier.
The impact of heat stress on milk production can be reduced by using shading, ventilation, spray and fans, according to Dennis Armstrong, who retired as a UA Cooperative Extension dairy specialist and consults for dairy companies in Saudi Arabia.
The Saudi barn style was developed in the 1980s for milk production in the harsh climate of the Arabian Desert, Armstrong said.
The Saudis call this type of barn “Arizona style” because the UA faculty assisted in developing the technology and practices necessary to have an economically viable milk production in the desert, said Caballero.
The barn mainly consists of a roof to provide shade for cows and to prevent the sun’s radiation from warming the animals while having open space to allow for maximum air flow. Additionally, it has fans and misters to cool the air temperature and cows’ bodies.
In the mid-1990s, Arizona dairy farmers began building new facilities using the Saudi style barn, said Armstrong. The key to success of transferring Saudi style barns to Arizona was having the necessary capabilities, such as a trained staff to maintain the cooling equipment.
The cooling system demands constant maintenance as the fans are prone to break down, said Vincent Arrington, the manager of Caballero Dairy Farm. During the night, the farm has a technician on call in case a major cooling system component, such the mister’s water pumps, breaks down.
“You got a lot of moving parts,” said Arrington. “A lot of stuff gets broken all the time.”
From 2007 to 2013, the annual milk production per cow in Arizona went up by 400 pounds which is a 2 percent increase, according to the U.S. National Agricultural Statistics Service 2014 annual bulletin.
Through economic and climate projections for the next 20 years, it is unlikely that dairy farms will leave Arizona and other warm states because farmers can use shade and cooling systems to mitigate the modest increase in the temperature, according to a study published by Nigel Key, an economist from the U.S. Department of Agriculture.
Proximity to feed and markets are two main factors dairy farmers considered when deciding the location of their facility, Key said.
In 2006, Caballero decided to build his new farm in Eloy because it is close to alfalfa fields and markets in Arizona.
“Arizona is home,” said Caballero. “That has value.”
All of the equipment is for the comfort of the cows, Caballero said.
“Why would you be a school teacher if you didn’t like children?” he said. “Why would you want to be a dairyman if you didn’t love your animals?”
Musherf Alamri is a reporter for Arizona Sonora News, a service from the School of Journalism with the University of Arizona. Contact him at firstname.lastname@example.org
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