Cows are surprisingly good at math, better than you might first imagine.
Herds approaching 40,000 lb of milk will have mature cows peaking at 140 lb per day or more. So if you expect mature cows to peak at that level, you have to ensure they eat enough feed to support that production.
Here’s how the math works, says Mike Hutjens, professor emeritus in dairy cattle nutrition at the University of Illinois.
First assume that feed contains 0.73 megacals (mcals) of energy per pound. A mature Holstein requires about 10 mcals of energy to simply stay alive. That means she needs 13 lb of feed for basic body maintenance.
Also assume it takes 0.32 mcals of energy to produce a pound of milk. That means each pound of feed should produce 2.3 lb of milk. So to get 140 lb of milk, a mature Holstein needs to eat about 61 lb of feed. Add that to her daily maintenance, and her total dry matter intake has to reach 74 or 75 lb/day.
Lo and behold, if you talk to top herds such as Jeff Horsens (p. XX) or Dan or Paul Siemers (p. XX), their high groups will approach this level of intake.
Such high levels of intake were unheard even 10 years ago. But the math, confirmed by the cows themselves, show high levels of feed intake are needed to sustain these high levels of milk production. “These girls need access to groceries,” says Hutjens.
High levels of feed intake require large amounts of quality forages because they underpin and support rumen function. Cows can consume about 3 ½ to 4 lb of forage undigestible neutral detergent fiber (NDF) for every 1,000 lb of body weight, says Hutjens. So a 1,500 lb. Holstein can only eat about 5 ½ to 6 lb/day of undigestible forage NDF to sustain optimal rumen function before they are physically “full,” reducing rate of passage and feed intake.
“The fiber has to be effective, but then it has to get the heck out of the way so that feed intake can be maintained,” he says. That’s why alfalfa quality and properly fermented corn silage is so critical. High-fiber or poor-quality feeds simply don’t have the passage rates to support high levels of milk production.
Data from Dairyland Labs (see chart), with forage testing labs in Minnesota and Wisconsin, shows the range of undegraded NDF (240 hours) by forage source from last year’s crop. BMR and conventional corn silage have a much tighter range of uNDF240 than legume and grass silages. But there’s enough variation in all these feed sources that harvest management is critical.
Even small mistakes, or weather delays, mean the difference between putting up high-quality forage versus average or even poor. And once an average or poor crop is ensiled, it’s difficult to improve fiber digestibility and passage rates through ration balancing. Highly-digestible commodities such as cottonseed, corn gluten feed and/or soy hulls might be used to replace some poorer forages, but there are limits to how much can be substituted, says Hutjens.
Above 70 pounds of milk, nutritionists might start supplementing added fat to ensure energy levels in the diet are sufficient. Fuzzy cottonseed, animal fats and then inert fats might be added as production rises.
After about 80 lb of milk production for Holsteins or 68 lb for Jerseys, rations often need to be supplemented with rumen-protected amino acids to ensure adequate levels of protein. Depending on the diet, first methionine, then lysine and even histidine might need to be added.
Feed additives also come into play, particularly if they’re proven to increase feed efficiency. “Monensin is a no brainer because it increases feed efficiency, reduces protein degradation and can decrease ketosis and displaced abomasums,” says Hutjens. Buffers, yeast and probiotics can also be abomasum appropriate, depending on starch levels and how rations are formulated.
The dry cow and transition periods are also critical to high production. “Cows have to come out of the chute and be batting 100% after calving,” says Hutjens.
There are no secrets
“There is no secret foo-foo dust that will get you high production,” says Rick Lundquist, a dairy consultant with Nutrition Professionals with clients in the Midwest and across the south from Arizona to Florida.
He puts the keys to high milk production even more bluntly: “Cow comfort and excellent forage – if you don’t have these, the rest doesn't matter.
“To achieve high milk production, minimize unneeded energy expenditures by the cow,” he says. Problems arise when dairies have:
- Uncomfortable stalls that prohibit the cow from lying down enough.
- Heat or cold stress
- Cows walking too far for milking.
- Cows locked up for extended periods.
- Time away from feed and free stalls.
“As for nutrition, good, consistent quality forage and digestible fiber are the key,” he says. “High production depends on digestible fiber of the forage. NDF digestibility drives it.
“So harvesting at the right time and at the right moisture is critical. You can’t let alfalfa haylage get too mature, and with corn silage, you have to have the right length of cut, good kernel processing and shredding of the long fibers,” he says.
For high production in the next lactation, the dry and transition period must be trouble free. Close-up and transition cows can’t be crowded, need comfortable stalls and easy access to feed. “Things that work well are anionic diets and protected choline, and also checking blood calcium and urine pH,” he says. “But all of these things won’t make up for calving in a poorly ventilated, crowded, close-up facility.”
One game plan
Getting owners, managers, workers and custom operators all playing out of the same play book and executing the same game plan is a key factor to high and sustained milk production, says Marty Faldet. Faldet in a consultant with GPS Dairy Consulting, working with herds ranging from 400 to 6,000 cows in the Midwest.
For example, he tries to hold both pre- and post-harvest meetings with a dairy owner, employees and custom operators to ensure everyone’s on the same page. “What hybrids you seed to how you harvest, pack, store and feed out is all critical,” he says.
Faldet puts a lot of his consulting focus on forage and feeding management. “Each farm is a little different in how they approach things and how they adjust to changing conditions. If we have three days of rain, do we have a Plan B and a Plan C in place as conditions change?
“If we have several loads of wet haylage that will ferment poorly, can we put that in a separate pile that can be fed as quickly as possible. That prevents butyric layers of feed forming in the main pile and creating issues for a longer period of time,” he says.
The more productive farms act quickly and decisively when things don’t go as planned. “These farms make a decision and fix it rather than delaying the correction,” says Faldet. Employees then get the message that things need to be done correctly all the time and when things break, they need to be fixed promptly.
“The other thing I see a difference on dairies is the whole culture of the farm: How they communicate, what expectations are, whether protocols are followed and things are done on a timely basis,” says Faldet.
Farms that communicate effectively have a much better chance of success, he says.
Note: This story appears in the July 2017 issue of Dairy Herd Management.