Building and balancing rations for dairy cows is both an art and a science. One crucial aspect of this process is evaluating the physical form of the ration, particularly the particle size. Why does particle size matter, and how do we accurately assess it? Let’s dive into the intricacies of this essential practice.
To begin the evaluation process, we must first obtain a representative sample of the feed. Sampling along the feed bunk ensures a comprehensive overview of what is being offered to the cows. By combining multiple samples into a composite, we create a uniform representation of the ration.
As we collect our samples, we pay careful attention to maintaining the fines—the smaller particles that contribute to the overall texture and consistency of the feed. Once combined, the sample is ready for evaluation.
The three-box system is a widely utilized method for assessing particle size. This system, enhanced with a four-millimeter screen for defining effective fiber, allows for precise analysis. Stacking the three boxes together and adding the sample—typically around 500 grams for a total mixed ration (TMR)—sets the stage for the evaluation process.
Shaking the sample five times and rotating the box between each shake ensures thorough mixing and separation of particles. This process is repeated for eight cycles, with attention given to observing the distribution of feed particles across the boxes.
By removing the top box after it has been adequately shaken, we can assess the distribution of particles in the subsequent layers. This step is crucial for determining whether the forages or feedstuffs are effectively separated and distributed throughout the ration.
Once all three boxes have been evaluated, the feed samples are placed on individual plates for further analysis. Using a postage scale, each plate is weighed to determine the approximate weight of the feed samples from each box.
The final step in the evaluation process involves assessing the overall shakeout of the TMR. A balanced distribution of particles is indicative of an optimal blend, contributing to the nutritional integrity of the ration.
In summary, evaluating particle size is a critical aspect of ration formulation for dairy cows. By employing systematic methods such as the three-box system, farmers can ensure that their rations meet the nutritional needs of their herds, ultimately optimizing health and productivity.
