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The Study is Now Closed - Here is information on the Recruitment Materials used for the study.

Invitation to San Joaquin Dairies
If you would like more information about the study please contact the study lead investigator, Frank Mitloehner, at (530) 752-3939 or email at fmmitloehner@ucdavis.edu or contact the project coordinator, Diane Mitchell, at (530) 752-1810 or email at dcmitchell@ucdavis.edu.

The purpose of this study was to collect scientifically accurate data of the exposure of dairy workers to dust and ammonia.  The workers’ lung function was monitored at the same time to see if their work exposures had any effect on their breathing.  The idea is to compare their breathing at the start and end of their shift to see if any changes that occur correlate with the materials collected on the samplers they wear. We studied workers directly involved in tending cows at the dairy, with a maximum of 8 per shift.  Depending on the number of workers per dairy, we collected data over at least one night shift, and usually 2-3 day shifts. The following description of the study was used to supply information in advance of the team's arrival at a dairy.

What will happen on Study Days:

backpackThe volunteers will wear a light backpack which contains a pair of air samplers, an ammonium monitor and a pump during their work shift. The air samplers are located only on the backpack (see photo on the right).  The equipment will allow them to work normally.  We will ask the workers questions before and after their work shift to find out where and what sort of tasks they have done (to match to the air samples collected), and find out about their health. No names will be attached to the questionnaires, so answers will be kept as confidential as possible.  We will also give them a breathing test before and after work to see if there are any changes over the work shift.

We will have to ask the workers to arrive earlier than their work shift normally starts  40- 50 minutes in order to complete the testing before they start work
 –The test is in 3 parts -  the breathing test, the questionnaire and the back pack air sampling set-up.


At the end of their shift it will take about 30 minutes to take off the equipment, do another breathing test and answer some more questions about what they actually did in the work period.

We would like to give the workers who help us a small gift such as a soccer ball or ball cap, and those that complete all three components on the same shift will also receive a store gift card.  Also at each visit small samplers (the stationary samplers) would be mounted on a tripod to monitor the air. They would be placed in the milking parlor and freestall areas, making sure they are out of the way of animals and do not interfere with work. We also have some larger monitoring equipment (please see attached page)

(Left photo: stationary equipment used to monitor particles in the air at dairies)


We expect to monitor about 21 workers total. They have to be male and aged 18-65 and work at least a 6 hour shift.  We would like to survey about 8-10 workers who milk the cows and the remainder would be others who work on the dairy outside the milking parlor.
That is  people who;

  • Birth / care for calves, heifers, dry cows and bulls
  • Tend sick / injured animals or do routine medical care or insemination on cows
  • Feed or mix and distribute feed to animals
  • Do maintenance work in the milk parlor, or corrals
  • Clean / rebed / scrape freestalls or corrals
  • Move animals
  • Flush waste or do lagoon maintenance.

Thank you so much for your help! 
We will have a team of about 7 working at your dairy from the total team: Frank Mitloehner (PI), Diane Mitchell (coordinator), Veronica Arteaga, Chelsea Eastman, Becky Gallo, Johnny Garcia, Victor Hernandez, Rona Silva, Erik Rodriquez and Gloria Andrade.

Dairy Worker Recruitment
Dairy workers will be recruited by an oral presentation approved by the UC Davis Internal Review Board for Human Subjects. This poster will be left at the dairy facilities to explain the study and what subjects would be asked to do:





The Cal-Dehri Study is a collaboration between University of California, Davis departments of Animal Science and Public Health Science, and Colorado State University and is funded by a grant from the National Institute of Occupational Safety and Health (2006-2011) Reproduction of material on this web site is hereby granted solely for personal use. No other use of this material is authorized without prior written approval ofthe UC Regents.

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