The motivation to feed for zero refusals is most often due to the desire to maximize income over feed cost.
The cost of total mixed rations (TMRs) in the Midwest is usually around 10 cents per pound of dry matter. If we feed for a 3 percent refusal, that will be 1.5 to 1.8 pounds of extra dry matter being fed per day. This would result in an extra feed cost of 15 to 18 cents per head per day, or approximately $6,000 per year for every 100 cows in the herd.
However, most farms find at least some salvage value in these refusals by feeding it to heifers, far-off dry cows or even low groups of lactating cows. But if there are no options to salvage some value from this extra feed, it needs to be completely included in the total feed costs of milk production.
It makes sense that if we want the maximum return on our feed investment, we should feed no more than what the cows are going to eat. The logical thought is, “Why waste feed?” But feeding for zero refusals isn’t for everyone, and it’s going to require that everything in your feed management program is perfect. Here are a few important areas to consider to make this concept work:
1. Manage forage moisture variation
You’ll need to have an excellent program for managing the moisture variation of your forages. Farms that are excelling in a zero refusal program check forage moistures daily. Checking two to three times per week is likely the minimum frequency needed. Keep in mind that there may be some sampling and testing variation, and the best way to manage this is to use a rolling average of the moisture tests rather than making any drastic changes on a daily basis.
2. Use a silage defacer, and mix the defaced forages
The face of a bunker silo can have significant moisture variation from one area to another. Using a silage defacer helps to ensure silage is taken from the entire face of the silo and certainly does a great job of premixing the silage. But an additional step that has been successful in reducing moisture variation is to mix the forages with the loader bucket after they have been defaced and then piled on the bunker floor.
3. Consistent feed delivery and push-ups
Your feed delivery and push-ups will need to occur at exactly the same time every day. Programs that require cows to clean up all their feed before they “earn” fresh feed are usually a disaster. Feeding time could be delayed by up to several hours in this scenario. We know that cows really like consistency, and even a slight variation in the time of feed delivery from day to day results in a loss of milk.
The consistency of the timing of feed push-ups is also important to be able to accurately monitor intakes. A skipped or even just a late push-up can make a big difference in the amount of feed that the feeder sees in the feedline in the morning.
4. Account for all cows in the pen
You’ll need to make sure the feeder knows exactly how many cows are in the pen. This job has gotten easier now that more feed management programs interface with the herd management software. Otherwise, a good system will need to be in place to communicate cattle movements from pen to pen. We need to also consider how often cows mistakenly end up in the wrong pen. If this is a regular occurrence, it will be difficult to supply an exact amount of feed to that pen.
5. Focus on feed redistribution
Just being good at pushing up feed won’t quite be good enough. You’ll also need to be good at redistributing it. Having all of the feed in just one area won’t allow enough access for the entire pen of cows. Any feed remaining in the feedline will need to be distributed as evenly as possible along the entire length.
6. Understand the impact of overcrowding
Being overcrowded will make the penalty for running out of feed more severe. The degree of overcrowding will impact what percentage of the herd can eat at once. The less dominant cows are likely to be more severely affected by a bunk that is empty for the last few hours before feeding.
Research from the Miner Institute reported that the combination of overcrowding and five hours of an empty bunk (similar to a pen running out of feed in the early morning hours) resulted in much higher levels of subacute rumen acidosis. The occasional use of trail cameras can be helpful in determining what time of the night a pen actually runs out of feed.
7. Determine the current refusal rate
The first step in managing refusals is to find out what yours actually is. This will require weighing the refusals for each pen and doing a little math to arrive at your current refusal percentage. If you’re at 5 percent now, you could try cutting that in half and see how many days out of the month any pens are out of feed for an extended period. You might find out you actually really need to be at 5 percent refusal to avoid frequent empty bunks.
It’s best to be generous when it comes to feeding the post-fresh group, and many nutritionists are comfortable with 8 to 10 percent refusal. The cost of an empty bunk is just too high for this group in terms of health and milk production. Also, since cows are entering and leaving this group on a daily basis, it presents an even greater challenge to getting the amount of feed just right.
We know how important feed efficiency is to overall profitability, and survival will require getting the most milk from every pound of the ration. But profitability and survival are also very dependent on marginal milk production. If even 1 pound of marginal milk is lost, the savings of a zero refusal program will be minimal. 
-
Ron Munneke
- Dairy Nutritionist
- Purina Animal Nutrition
- Email Ron Munneke
