TMR Evaluations of Heifer Diets – Jon Rasmussen, Vita Plus

By Jon Rasmussen, Vita Plus technology specialist

The leading cause of inaccurate ingredient weighing is load cell binding from dirt and broken structures.  Check to ensure the load cells are clean of dirt and all the support structures are functioning as they were designed to.

After this visual inspection, check the weighing system to make sure the load cells are functioning properly.  As a simple check, use a ladder to hook over the top of the mixer and safely climb over each load cell to check if the scale changes by your bodyweight.  It’s important to do this at each load cell with an empty mixer, partially filled mixer and a full mixer.  Performing the check at multiple weights will help determine if the mixer has a binding challenge the visual inspections failed to detect.

Next, check how well the TMR is mixed and distributed at the feedbunk.  Ask your nutritionist to help with this task. This involves following the TMR mixer as feed is delivered to collect five to 10 separate samples of TMR, approximately 3 pints in total volume, for the Penn State Shaker Box.  Shake out the samples in the order you collected them.  The total variation of the bottom pan should be less than 5 percent.  This will indicate how well the ingredients have been processed and mixed.  An increased variation indicates that the TMR mix consistency can be improved. If this is a challenge, we can evaluate the ingredient loading order, the particle sizes of the ingredients, mixing time and physical components of the TMR mixer.

The last step of the TMR evaluation is the feedbunk. Check to see how close the feed refusal resembles the fresh feed.  Again, the Penn State Shaker Box could be helpful to determine the degree of sorting by determining what ingredient portions of the diet remain.

As you look at the feedbunk, also inspect the heifers for growth consistency, any visible health challenges, and their feet.  Are the front toes growing normally or do they show signs of pushing hard at the bunk to reach the feed?  If you see signs of abnormal growth, is it from overcrowding, limited feed, reaching for feed, design of the feedbunk or other challenges?  Observe how much refusal is left and the time the heifers ran out of feed.  If the pens are overcrowded, it is often beneficial to have some refusals left to prevent the heifers from pushing and reaching at the feed rail.  If the pen is not overcrowded, you may be able to get to an empty bunk prior to feeding time without challenging the performance potential of the heifers.

Routinely completing these TMR evaluation steps will help improve your heifer performance and, ultimately, your bottom line.