FeedFIT – Trimming Feed Costs through Weighbacks

Is it weighbacks or refusals that you have left in the feedbunk?

Words matter. Let’s get our terminology right first.

Refusals is feed that is left that is mostly inedible for high producing cows. It doesn’t look like the original high cow TMR. It might contain longer particles like straw, pieces of cob or it is heating.

Weighbacks is feed that is left that is like the TMR from the day before. Cows are eating this like the original TMR. Maybe it’s not perfectly the same, but it is within 10% of the original ration specs.

Do your feeders understand the difference?

For high producing cows, I would argue that the goal is 0% Refusals and 2-5% Weighbacks. If the leftovers in the morning are essentially refusals, we need to turn the clock back and ask why it doesn’t look like the original TMR? If we are left with a lot of long particles and cows are sorting, then how do we change particle size or TMR consistency to prevent this sorting? If we have a refusal that has cobs or another ingredient cows are leaving behind, do we need to look at processing of corn silage? If we have a TMR that is a bit slimy or heating because of summer heat, do we have a fresh forage issue (facing/storage) or do we need to add an acid for the summer?

What do we do with weighbacks?

1. Throw them out. This is 2022, not 1972. We know better.
2. Feeding weighbacks to heifers on the farm. This was more popular 15 years ago when most dairies had breeding age heifers on the farm. From a nutritional standpoint, heifers from 5-12 months do well on weighbacks. Maybe too well in some cases but that’s not the main problem. Let’s take a heifer eating 15 lbs. of dry matter a day. With a targeted heifer diet, we can likely hit 8 cents per pound of dry matter (or less). The lactating TMR at 12 cents per lb. of dry matter leaves a difference of 4 cents, or $0.60/hd/day on these heifers or maybe $0.30/hd/day if it’s half their diet. It’s a simple solution on many dairies but it is not cheap. If you want to discount the weighbacks 10% in value, ok… but they’re not free.
3. Feeding the weighbacks to feedlot cattle. This has become more common in the last few years; there is a pen of “steers” that receive 100% of the weighbacks. For the steers in the early growth phase, the economics are like the heifers: a lactating dairy TMR that is overpriced for these animals. For steers that are in the finishing phase, the TMR is not balanced correctly to finish these animals quickly or economically as a typical finishing feedlot diet.
4. Refeeding the weighbacks to lactating cows. This can work well if your weighbacks look very similar to the original TMR. An inclusion of 3-5% on high groups could be a starting point where 10-15% might be possible on your pregnant groups. Keeping this percentage lower on the high group should protect you from unexpected changes in the weighbacks. If they turn into refusals because of summer heat, change your strategy.