The creator is a professor emeritus of animal sciences on the College of Illinois, Urbana.
Mike Hutjens
Feed effectivity has turn into a typical measurement reported in analysis journals. Not solely is it an financial measure on dairy farms, but it surely has turn into a part of our genetic base in deciding on bull semen, too. Feed effectivity displays power conversion to take advantage of manufacturing. A one-tenth unit enhance — from 1.4 to 1.5 kilos of three.5% fats corrected milk per pound of dry matter consumed — displays a 30- to 35-cent acquire in income per cow per day.
One other measure will likely be protein effectivity on dairy farms. With excessive protein feed costs, constructing rations that enhance the conversion of feed protein to take advantage of protein can have financial worth.
Milk protein can be essentially the most valued milk strong at $2.50 a pound in July 2021. Customers will count on improved protein effectivity to cut back nitrogen losses into the setting as urinary nitrogen losses and ammonia fuel emissions.
Making the calculation
On-farm protein feed effectivity could be calculated by figuring out the next values.
1. Calculate the kilos of crude protein consumed by your herd. An instance could possibly be 50 kilos of dry matter containing 16.5% crude protein leading to 8.25 kilos of crude protein consumed per cow per day.
2. Calculate the kilos of true protein produced by your herd. An instance could possibly be 75 kilos of milk containing 3.1% true protein (whole or crude protein can be 3.3%), leading to 2.33 kilos of true protein per cow per day.
3. Divide 2.33 kilos of true protein by 8.25 kilos of consumed crude protein, leading to a protein feed effectivity of 28.2%. This worth is typical for dairy herds.
Extra factors
A number of assumptions have been made in these calculations. If whole or crude protein content material of the milk protein was used, the protein feed effectivity would climb to 30% (3.3% milk protein instances 75 kilos of milk divided by 8.25 kilos of feed crude protein).
No adjustment for physique weight acquire would enhance protein effectivity as a part of the feed protein was partitioned to tissue substitute. The same benefit can be for first lactation cows which might be rising, resulting in added muscle. Likewise, close-up dry cows partition amino acids to fetal development and colostrum synthesis. Laptop modeling packages might fine-tune these calculations, however dairy farmers would not have entry to those values to enter into their calculations.
Utilizing the calculations for on-farm protein feed effectivity from our working instance, Desk 1 demonstrates how protein feed effectivity could be improved by making feeding adjustments on dairy farms.
Case A is identical calculation mentioned earlier for baseline comparisons. Case B drops feed crude protein by one share level from 16.5% to fifteen.5% by making ration ingredient adjustments whereas sustaining milk yield and elements. Case C raises milk yield from 75 to 80 kilos of milk by means of feeding methods that enhance metabolizable protein. Case D elevates the p.c true protein from 3.1% to three.3% by fine-tuning amino acid stream.
Elite dairy farms at the moment obtain leads to Case D. Cornell College researchers recommend that by constructing rations utilizing primarily corn silage, restricted grass hay, heat-treated soybean meal, blood meal, and rumen-protected amino acids, protein feed efficiencies can strategy 40%. The New York food plan consisted of 46.1% corn silage, 8.5% grass hay, 15.1% finely floor corn, 7.1% corn gluten feed, 7.9% soybean meal, 2.1% soy hulls, 4.1% heat-treated soybean meal, 1.2% molasses, 1.6% palm fatty acid complement, 0.12% urea, 0.09% rumen protected methionine, 2.18% blood meal, and three.9% mineral/vitamin premix.
Ration balancing choices
Utilizing a rumen modeling program, areas to regulate rations could be recognized for bettering protein effectivity. Most packages will point out the extent of milk supported by the metabolizable protein (from microbial protein and rumen undegraded protein sources or RUP). This system additionally will calculate the extent of rumen degraded protein (RDP) required.
If the RDP stage is over 20 grams of extreme RDP, this nitrogen could also be misplaced in urine excretion and elevated milk urea nitrogen (MUN) ranges. To decrease the extent of RDP, feed ingredient adjustments will likely be wanted (much less haylage excessive in RDP, for instance).
If the RDP stage is under necessities, including extra haylage or urea could be thought-about. If RUP ranges are poor, changing a part of the soybean meal with heat-treated soybean meal is one various.
The rumen mannequin program additionally could predict the extent of metabolizable lysine and methionine wanted for the goal stage of milk and milk protein content material. If amino acid ranges are low, contemplate various feed components (akin to blood meal for lysine or corn distillers grains for methionine) or add rumen-protected amino acids.
Six on-farm instruments exist
1. Evaluate your milk protein content material to breed averages (Desk 2). In case your herd milk protein share is under the breed common, you might have a chance to enhance milk protein based mostly on breed genetics.
2. In case your herd is on a Dairy Herd Info (DHI) testing plan, search for the milk protein percentages within the first 100 days in milk by first, second, and third plus lactation cows. Knowledge from the Dairy Report Administration Programs (DRMS) reported decrease milk protein content material for all Holstein herd milk yield ranges and lactation quantity within the first 100 days in milk. Vital enhancements in milk protein could also be obtainable in your herd.
3. Evaluate the ratio of milkfat share to take advantage of protein share in your herd to breed values in Desk 2. As milkfat p.c goes up, milk protein p.c ought to climb in a parallel relationship. If milk protein share take a look at ratio is lower than 75% for Holsteins, study explanation why milkfat p.c is excessive (feeding additional fats, for instance) or milk protein take a look at is low.
4. MUN is one other software to find out if rumen microbes are capturing rumen ammonia from RDP sources as microbial protein or extra ammonia is absorbed throughout the rumen wall and transformed to blood urea nitrogen by the liver. Goal MUN ranges from 8 to 12 milligrams per deciliter (mg/dL) with decrease ranges reflecting higher protein effectivity.
5. Grouping cows by stage of milk yield can enhance protein effectivity in comparison with feeding a one group whole blended ration (TMR). Utilizing the bottom herd values in Desk 1, feed efficiencies have been calculated at numerous ranges of milk yield and are proven in Desk 3. Dry matter intakes have been decrease as milk yield declined.
6. Administration components can also enhance protein effectivity. Michigan State researchers urged the next enhancements can bolster protein effectivity above the herd based mostly protein effectivity (could possibly be 28.2% as listed within the base worth). These components both enhance milk yield and/or scale back feed wants.
• Add 0.4 level to be herd base worth with a ten% enhance in milk yield
• Add 0.5 level by including one further lactation quantity (longevity)
• Add 0.3 level by lowering calving interval by one month
• Add 3.1 factors by lowering feed waste by 10%
Varies in people and cows
Protein feed effectivity as expressed by protein sources that people can not devour could possibly be 100% when feeding corn silage, grass forage, hominy, distillers grains, corn gluten feed, and urea. Cornell College analysis suggests the theoretical most is 40% to 45%, whereas on-farm most protein effectivity can attain 38% to 40%.
Sooner or later, efficiencies could also be measured as kilos of milk solids per unit of feed dry matter, milk solids per acre (pasture-based programs), and greenhouse gases per pound of milk, cheese, or different dairy merchandise. Effectivity will likely be key in future dairy farm measurements.