Nutrition Plus

Dairy Nutrition Plus

Volume 12, Issue 6 November 2016

Use New Forage Tests To Build Better Rations

Use New Forage Tests To Build Better Rations

Not all forage fiber is the same. And neutral detergent fiber (NDF) doesn’t tell you everything you need to know to formulate high forage diets for high producing dairy cows.

Total NDF is not a good predictor of animal performance, explains Dave Combs, dairy nutritionist at the University of Wisconsin. To understand how cows will perform when fed forage you need to know how fast the forage fiber is digested and how much of that fiber is not digestible (uNDF).

Research during the last decade has led to several new forage tests. Nutritionists can use these new tests to build better rations to optimize cow health and performance. The first step is learning a new alphabet. TTNDFD, aNDFom, and uNDF240 are just a few of the new tests available.


TTNDFD stands for total tract neutral detergent fiber digestion in ruminants. Researchers at the University of Wisconsin were looking for a quick, low-cost test that could accurately determine how fiber is utilized in cows. Previous in vitro tests looked at digestion at a given point in time, 24 hours, 30 hours, 48 hours but those tests did not correlate well to animal performance, says Combs. And uNDF is only part of the equation.

TTNDFD combines uNDF with rate of digestion to provide more accurate estimates of animal performance. The test utilizes an NIR scan to estimate the uNDF as well as the disappearance at 24, 30 and 48 hours. These four factors are combined to calculate the rate of digestibility. TTNDFD can be used to compare digestibility of two different forages in the diet such as alfalfa to corn silage. Previous tests such as NDFD30 only allowed users to make apples to apples comparisons such as alfalfa to alfalfa or corn silage to corn silage. Test results are generally available the same day the sample is received, provided it arrives before the cutoff time. The test is currently available at Rock River Laboratory in Watertown, WI, and the University of Wisconsin.


aNDFom is a modification of the NDF test with amylase, sodium sulfite and ash correction. aNDFom provides a more accurate measure of NDF. Making hay in a hurry, using big chopping equipment and flood irrigation all can lead to some soil contamination of forages. The problem is that soil does not solubilize in NDF solution, and the result is inflated NDF results. “Inflation of the NDF content means the diet as formulated is lower in actual NDF,” says Mike Van Amburgh, dairy nutritionist at Cornell University. Intake and rumen health can both be compromised when NDF is not accurate.

Nutrition software uses NDF to calculate energy from available carbohydrates and effective fiber. When ash and soil contamination are not accounted for the amount of NDF and therefore the amount of energy available and the digestibility will both be inflated. Van Amburgh recommends that nutritionists use aNDFom in place of NDF. Benefits include better rumen health through greater rumen fill and better predictions of energy and protein supply due to more accurate numbers.


Before new tests were developed uNDF240 was the best measure of unavailable NDF. The test was done through in vitro incubation under specific conditions. But 10 days is a long time to wait for test results and forages don’t stay in the cow that long anyway. Commercial labs now provide uNDF240 through NIR analysis.

Research at Cornell University with uNDF has identified fast and slow pools of NDF. While research is ongoing, the data so far suggests that uNDF240 may be useful to predict dry matter intake.

Getting fiber right pays

Producers have gotten really good at harvesting high-quality forages. But sometimes there is not enough fiber in those forages, or digestibility is too low to meet the cows’ needs in order to optimize cow health and performance, explains Combs. At a minimum, cows need 30% NDF in the diet for rumen health. Fiber digestibility should be at least 42% to 45%. Failure to meet these minimums in fiber requirements can leave a lot of money on the table.

In corn silage we know that if starch digestibility falls from 98% to 95% the loss is 2 to 5 lbs of milk/cow/day. The same is true with fiber digestibility. Every two to three unit decrease in fiber digestibility reduces milk production by 1 lb/cow/day, says Combs. Corn silage has a wide range of digestibility – 30% to 51% as measured by TTNDFD. When fiber digestibility is low you can easily lose 7 to 8 lbs of milk per cow per day. That’s a lot of money left on the table. The new tests can help you build better rations to capture some of that lost milk production.

To learn more about these new forage tests, please see these papers:

“Relationship Between NDF Digestibility and Animal Performance,” presented by David Combs at the Western Canadian Dairy Seminar.

“How do We Make Better Decisions in Dairy Cattle Diets and Management with Forages and Nitrogen,” presented by Mike Van Amburgh at the Northeast Dairy Producers Conference.

Consultants Corner
Six Tips to Improve Feeding Accuracy

Noelia Silva del Rio
  • By Noelia Silva del Rio
  • University of California Davis

Feed is the single largest cost on a dairy. So why then do we settle for such low levels of accuracy when loading feed ingredients into the TMR mixer?

In a study of 26 California dairies using FeedWatch 7 feed management software (FMS) we found that deviation from target weight on individual ingredients ranged from — 78.7% to + 21.9%. The one-year study, which examined high-cow and high-cow-premix rations, also showed that the precision or accuracy with which an ingredient was loaded varied by ingredient. Alfalfa hay, corn silage and canola were the ingredients most often loaded with poor precision and limited accuracy. But rolled corn and almond hulls were consistently loaded with a high level of precision and accuracy.

There also was a difference among feeders. Five dairies had feeders that loaded ingredients with great precision and adequate accuracy, while three dairies had feeders that loaded ingredients with very poor precision and accuracy. These results show that ingredients can be loaded accurately. Following are six ways to improve feeding accuracy on your dairy.

  1. Set Goals
    Set achievable goals for feeding accuracy and share with your feeder. Remember, feeders are loading pounds. Dairies with large mixers may appear to have small loadinFg errors when measured as a percentage, but when measured in pounds the errors are large. Review FMS reports with feeders so they understand what is being done right and what areas may need improvement.
  2. Reevaluate the use of tolerance level
    In our study, the use of tolerance level allowed a deviation from target of > 2% in 46% of the ingredients. In four dairies 75% of the ingredient loads were below target weight. On those dairies, feeders were using the load weight as defined by the tolerance level as the target weight instead of the actual target weight. Use of tolerance levels for ingredients should be reevaluated and limited.
  3. Communication
    Managers and nutritionists often limit communication with feeders to negative feedback. Feeders get reprimanded for loading expensive ingredients over the target weight. However, this message has led some feeders to mistakenly conclude that on expensive items they should always err on the side of less than target weight. One of the feeders in the study loaded expensive ingredients accurately whereas inexpensive ingredients such as forages were often loaded significantly above target weight. Loading errors may result in a TMR with a nutrient composition that is different from the formulated one. That’s why communication with feeders should include what is being done properly, goals and suggestions for improvement.
  4. Listen to your feeder
    Take time to listen to your feeders, they have good ideas. After you share FMS reports, ask questions. For example, why do they think corn silage is consistently overfed? Did they run out of an ingredient and didn’t know what to substitute so total load weight is short? Are there too many rations to mix and not enough time in their shift so they hurry? Are some ingredients located too far away from the feeding center and taking back leftovers would be “too time consuming”? Is there a problem or limitation with the equipment? It could be that training or practice is needed. Remember, loading ingredients precisely is a learned skill.
  5. Consider premix
    When formulating rations be cognizant of the physical requirements to create that ration daily. For example, how many times does the feeder leave the tractor cab to load bagged ingredients? Are ingredients being loaded in the right order? At one dairy I observed a feeder loading a bagged ingredient first instead of fourth as the ration specified. This change compromises mixing uniformity. Adding small ingredients and bagged ingredients into a premix can help improve loading accuracy and mixing uniformity.
  6. Check the mixer scale
    Loading accuracy requires that the scale of the mixer box is properly calibrated. On dairies with an on-farm scale this can be easily accomplished; otherwise, the mixer box scale can be calibrated by hanging bags of known weight on each corner above the weigh cells. It is difficult to accurately load ingredients when the scale number bounces up and down. To minimize, make sure the mixer is parked on a flat surface. Then, check how much bouncing takes place, specifically while hay is being chopped. The extra work of chopping hay could increase scale bounce.

Loading ingredients with minimal error can be done. Five dairies in this study demonstrated a very high level of precision and accuracy. The feeders at one of the dairies I visited told me about a little competition they had to earn “bragging rights” for the most accurate loads. And each had the opportunity to earn a small bonus for a predetermined level of accuracy. Take some time to think about what you can do to set feeders up for success.

South African Feed Supplier Switches to SoyChlor After Trial

Feed was mixed in a Calan Super Data Ranger mixer.
Feed was mixed in a Calan Super Data Ranger mixer.

South African dairies served by animal nutrition company Nova Feeds may be learning about a better way to help prevent milk fever and other issues associated with subclinical hypocalcemia as a result of a study presented at this year’s ADSA ASAS Joint Annual Meeting in Salt Lake City. The objective of the study was to compare the effects of diets containing traditional anionic salts to those containing SoyChlor on feed intake and energy balance of pre-partum dairy cows.

The trial was completed this summer by South African-based animal nutrition company Nova Feeds. It demonstrated better intake with SoyChlor for cows of equal metabolic acid-base status. The results prompted Nova Feeds to discontinue production of their own branded anionic salts and instead start using SoyChlor.

Twenty-nine pregnant multiparous Holstein cows were enrolled into the trial approximately 60 days prior to calving. All cows were fed the same far-off dry period diet without anionic supplementation. At 21 days before expected calving date, cows were evenly assigned to one of the two treatments: Anionic Salts (AS), or SoyChlor (SC). Each group was fed fresh feed mixed every day, and residual feed was weighed back. Either AS or SC was incorporated into the diet to yield a calculated DCAD ((Na + K) – (Cl + S)) of -120mEq/kg. The AS supplement consisted of 55% ammonium chloride, 29% magnesium sulfate, and 16% ammonium sulfate.

Compared to a diet containing anionic salts, with both groups of cows at identical states of metabolic acidosis according to urine pH values, the cows fed SoyChlor:

  • Consumed more feed during week 2 and week 1 prior to calving.
  • Consumed more feed overall during the 3 week pre-partum period.
  • Maintained a better energy balance during the last week before calving.
Once mixed and weighed for each cow, feed was transported to Calan feeding stations in bags.
Once mixed and weighed for each cow, feed was transported to Calan feeding stations in bags.

Also, the SoyChlor diet delivered the same amount of metabolizable protein with nearly 1 percentage unit less crude protein in the diet, according to estimates by CPM. That is due to the true protein in SoyChlor compared to the ammonia in the traditional salt mix.

The study concluded that feeding SoyChlor to pre-partum dairy cows yields greater dry matter intake and energy balance than feeding traditional anionic salts. Based on these results, Nova Feeds now uses SoyChlor, rather than their old anionic supplement.

Beyond Bypass
Corn Silage Treatment Shows Promise

Corn Silage Treatment Shows Promise

New research from the University of Wisconsin reveals that treating corn silage with calcium hydroxide at harvest can improve dry matter intake and milk production. The research reported in the July issue of the Journal of Dairy Science compared the dry matter intake, digestion and lactation performance of cows fed treated whole plant corn silage, treated fractionated corn silage, brown mid-rib corn silage and conventional whole plant corn silage.

All cows received the same diet of approximately 40% corn silage, 20% alfalfa silage and 40% concentrate on a dry matter basis. The only effective difference in the diets fed was the silage.

The results showed that cows fed whole plant corn silage treated with calcium hydroxide had the highest dry matter intake and the highest milk production of all four diets. Cows fed the treated whole plant corn silage had a DMI increase of 4 lbs/day and a milk production increase of 10 lbs/day when compared to conventional corn silage. The chart below provides more details:

DMI lbs/d 52.03 53.35 54.67 56.22
Milk lbs/d 95.24 103.84 101.41 105.82
*WPCS = whole plant corn silage; BMR = brown mid-rib corn silage; TPL = toplage + treated stalklage; TRTCS = treated whole plant corn silage.

In addition, the treated whole plant corn silage also had the highest aNDF digestibility, the highest starch digestibility and the lowest fecal starch of all four treatments. The toplage/treated stalklage corn silage mix performed similar to the BMR corn silage.

Calcium hydroxide can be used to improve starch digestibility and was successful at doing so in this experiment. One potential downside with alkali treatments can be reduced aerobic stability of the silage; which can lead to changes that are detrimental to starch digestibility. While aerobic stability for whole plant corn silage treated with calcium hydroxide is a concern, the risk is less when treating fractionated corn silage, explains Dave Combs, professor of dairy nutrition at the University of Wisconsin. Fractionated corn silage also provides the ability to optimize rations thereby targeting the highest quality portion of the plant toward lactating cows and lower quality forages to other animals. More research is needed to answer the question of how best to utilize alkali treatments on corn silage and to optimize rations.

You can read the full article “The Effects of Calcium Hydroxide-Treated Whole-Plant and Fractionated Corn Silage on Intake, Digestion, and Lactation Performance in Dairy Cows” in the July 2016 issue of Journal of Dairy Science.

From the Maternity Pen
Use Nutrition to Support Her Immune System

Use Nutrition to Support Her Immune System

The transformation from dry to lactating can be downright challenging for dairy cows. A drop in dry matter intake before calving, negative energy balance, a suppressed immune system combined with increased susceptibility to metabolic and infectious disease can make it seem like cows are walking a tightrope.

While we have made great strides in transition cow nutrition — think DCAD diets — recent research has really helped illuminate the complex linkages between nutrition and immune response. “The ability of dairy cattle to resist the establishment of disease during the periparturient period is related, in part, to the efficiency of their immune system,” explains Lorraine Sordillo, veterinarian and professor at Michigan State University. But the immune system can’t function correctly without the right nutrients. That’s why nutrition-based management strategies should be a key part of any disease prevention program.

New research has revealed how key nutrients play a role in a properly functioning immune system. Here are a few points to keep in mind when formulating transition cow rations.

  • Body condition. Cows should be managed to achieve an appropriate body condition score both pre-and post-calving to avoid adverse consequences. Over-conditioned and under-conditioned cows each face unique challenges at calving.
  • Keep them eating. Reduced DMI can lead to an even greater negative energy balance which can compromise the functional capacity of the immune system and increase susceptibility to disease.
  • Fatty acids. Evidence suggests that fatty acids can directly modify immune cell functions by altering the physical cellular membranes and by regulating intracellular signals. The current research supports the concept of supplementing cows with polyunsaturated fatty acids (PUFA). Doing so can help improve the functional capacity of the immune system and its inflammatory responses.
  • Glucose. Mounting an immune response requires energy. The immune system must compete for essential nutrients that are already being used for growth, muscle accretion and milk production.
  • Antioxidants. Vitamin and mineral supplementation must meet two goals. It must provide what the cow needs to maximize production efficiency. And it must provide what the immune system requires to prevent oxidative stress and optimize immune cell function.

You can read Sordillo’s full paper, “Nutritional Strategies to Optimize Dairy Cattle Immunity,” in the June Journal of Dairy Science.

SoyChlor Makes Life Easier at this Idaho Dairy

Russell Paceley (left) of Simplot Western Stockmen’s consults with Connie and Mike Thompson’s son, Tyler Thompson (right) at Standing 16 Ranch.
Russell Paceley (left) of Simplot Western Stockmen’s consults with Connie and Mike Thompson’s son, Tyler Thompson (right) at Standing 16 Ranch.

Mike and Connie Thompson were new to the dairy business when they started taking care of 300 Holsteins in 1999. But they rose to the challenge. Over the years they developed a successful business with Standing 16 Ranch in Jerome, ID, and tripled the size of their herd. Connie attributes much of their success to hard work, late nights, and lots of research.

As their dairy has grown and evolved, so too has their knowledge of proper feeding and nutritional practices. But since the beginning, the Thompson’s have believed in DCAD (Dietary Cation Anion Difference).

“I can never understand why other dairies don’t do DCAD. It just seems so obvious to me how important it is,” Connie said.

Connie has never considered this integral piece of their management as extra work. To her, it’s a necessary act of prevention that eliminates the time and heartache bound up in treating sick cows. Any time the Thompsons have stopped their DCAD program with SoyChlor, the population of their hospital pens has instantly increased.

The Thompsons have included SoyChlor in their close-up dry cow rations for more than 15 years as part of their DCAD approach. They are able to adjust the amount of SoyChlor by 0.25 lb/cow increments on the farm, as changes in forage mineral content makes DCAD adjustments necessary. 

“If you wait until after that cow is sick you have to treat the sickness. You can treat a symptom, but you aren’t really fixing the problem,” Connie said. Years spent tending to the dairy’s hospital pens 5-6 days a week have taught Connie that preventative practices, from the start, allow for a truly healthy and profitable herd.

And the consistency of SoyChlor has allowed the Thompsons to consistently and easily prevent milk fever and the other costly disorders related to subclinical hypocalcemia.

“SoyChlor is one of those products that truly works,” said Connie. “SoyChlor makes life easier.”

To learn more about why SoyChlor is the preferred chloride supplement for close-up dry dairy cows, watch a series of new videos showcasing the product’s consistency and the team who oversees it.