In manufacturing feeds for feedyard cattle, nutritionist Reed Richardson says, “If you get it right, the animals will respond. If you get it wrong, the animals will respond. There is no bias on the part of the animal, and the body doesn’t fool itself.”
Dr. Richardson, director of the Center for Feed Industry Research and Education at Texas Tech University, draws a distinction between the quality of feed ingredients and feed integrity. High-quality ingredients are a good starting point, he says, but feed still can have poor integrity due to errors in formulating, handling, measuring or mixing ingredients, which cause variations within or between batches of feed.
Using a triangle, Dr. Richardson illustrates the critical components of cattle production. One corner represents environment, another is genetics and the third, feed integrity and nutrition. For feedyards, he says, the best opportunity for improvements in productivity is in the area of feed integrity. “Animals thrive on a routine and respond better if feed is low in nutrient variation, high in integrity, similar in moisture content, texture and rate of energy availability,” he says.
Quality in, quality out
As many as 100 different ingredients are going into feedyard rations, offering plenty of opportunity for variability. Quality control of incoming ingredients, Dr. Richardson stresses, is crucial to predicting the quality of a ration, and an important first step is accurate sampling and complete examination of ingredients prior to unloading. There are, however, no established, standardized methods for sampling feed ingredients. Feedyard managers should work with their nutritionists to set the operation’s sampling and inspection procedures, and put them in writing in a Quality Control Procedures Manual.
Kansas State University extension grain science specialist Tim Herrman agrees, saying ingredient quality is the foundation upon which an animal ration is built, and that a program for evaluating ingredient quality is an essential component of a successful feed-processing operation. “Routine evaluation of finished feed quality will help ensure proper ingredient storage, proportioning, grinding and mixing,” he adds.
As a starting point for managing integrity in feedyard rations, Dr. Richardson suggests checking all incoming ingredients for moisture, color, off odors, foreign materials, uniform texture, evidence of heating and deterioration due to biotoxins. Dr. Herrman also stresses the importance of examining the physical properties of ingredients, such as bulk density, purity and particle size. These properties, he says, determine how the material unloads, conveys into and out of bins, stores and performs during processing.
Bulk density, Dr. Herrman notes, can vary significantly for the same ingredient due to differences in particle size, moisture content or compaction. Blending ingredients that differ widely in bulk density might require the use of a binding agent such as fat or molasses. Dr. Herrman also recommends loading mixers using an ingredient sequence that optimizes the blending action of the mixer. For example, he says, high-density ingredients should be added early to vertical mixers and late in the batching sequence for horizontal mixers.
Particle size of ground grain performs a critical role in determining feed digestibility, mixing performance and pelleting, Dr. Herrman adds. “Periodic particle-size evaluation is a necessary component of a feed-manufacturing quality-assurance program.”
The next step in assuring feed integrity is routine sampling and analysis to determine the nutrient value of ingredients. Dr. Richardson cites the lack of analysis of feed ingredients as a key challenge in cattle-feeding operations. Feedyards, he says, often formulate rations based on the book value of ingredients, while actual values can vary as much as 20 percent from the estimate. Ideally, feedyards would test all ingredients and adjust their formulations based on those analyses.
In the real world, Dr. Richardson acknowledges that commercial feedyards take delivery of some ingredients on a daily basis and turn them over rapidly. With laboratory analysis taking days or as much as a week, sending samples out could seem pointless for batches of ingredients that cattle eat before results come back. One possible solution for feedyards is to invest in a near-infrared reflectance analyzer, which can provide rapid testing of grain for crude protein, starch, fiber and oil content. The NIR devices also can analyze a mineral content and other feed attributes with the proper calibration, providing results in a matter of minutes. Nutritionists sometimes disagree regarding the accuracy of the NIR analyzers for testing feed ingredients, but Dr. Richardson says the test is quick and accurate enough to offer a significant improvement over doing nothing. The cost of these units and the investment in training a crew member to operate it probably limit the use of NIR analysis to the bigger commercial operations.
Lacking their own testing facilities, feedyards still have the opportunity to sample ingredients for analysis, especially those purchased in large quantities for feeding over time. In the case of ingredients that are fed quickly rather than stored, routine testing can help establish a baseline and identify significant fluctuations in quality.
The goal in sampling any lot of ingredients or finished feed is to obtain samples that are representative of the lot in question, Dr. Richardson stresses. A wrong answer, which may arise from incorrect sampling, incorrect handling of samples or analytical error, is worse than no answer.
Dr. Richardson says cattle feeders can evaluate the overall integrity of feed delivered to the bunks by determining the level variation in four major areas that affect feed consistency:
Variation of incoming ingredients
Variation in feed-mixing efficiency
Variation in efficiency of delivery of mixed feed from mixing point to the animals
Variation in analytical procedures
Formulating rations on paper is easier than delivering a balanced ration, Dr. Richardson concedes. But, he adds, “Good-quality feed is often taken for granted, and poor-quality feed is remembered after the cattle are sold.”