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A new publication from the Iowa Pork Industry Center at Iowa State University helps producers evaluate feed uniformity and identify ingredients that may affect herd outcomes.
“Mixer Uniformity Test Procedure” IPIC 210 outlines proper sampling procedures, testing methods for trace substances, and helps in analyzing and interpreting results. ISU extension swine specialist Mark Storlie is the author of this publication.
“The mixer design will direct your sampling procedure,” Storlie said. “Samples should be taken at, or as close to, the mixer discharge as possible.”
The publication explains sampling techniques for both horizontal and vertical mixers. Horizontal mixers use a grain probe to collect 10 samples from set locations inside the mixer. For vertical or continuous proportioning mixers, samples should be collected as the feed is discharged, with careful timing.
Salt, trace minerals, and synthetic amino acids are commonly used as tracers to test uniformity. Samples can be sent to a lab or sometimes are tested onsite.
“A mixer uniformity test should be conducted within 90 days of installation of a new or replacement mixer, or periodically (minimum once every one to three years),” Storlie said.
The publication also has guidance on interpreting test results and includes a link to the Feed Uniformity Test Tracker Excel spreadsheet, created by Storlie for calculating results. Consistent testing establishes a routine for producers, which in term helps their animals maintain a healthy status and continued growth.
April 18, 2025 - Iowa State University
