Getting dry cows in a milking mood
By Steve Fairchild

Notes from the MFA Dairy Innovatores series.

Except perhaps for a laying hen, a high-producing milk cow is the hardest working animal in agriculture. And to stay

productive, a dairy cow has to shift a lot of gears from just before she calves until she becomes a member of the milking string.

A key to making this transition successful is to maximize dry matter intake (DMI), said Dr. Phillip Jardon, veterinarian and dairy specialist with West Central Cooperative, Ralston, Iowa. Jardon spoke at the 2006 MFA Dairy Innovators Seminar. Goals during the dry period: help the cow’s rumen adapt; maintain her immune system; and maintain normal calcium levels and a positive energy balance.

“Cows like to be bored,” said Dr. Jim White, MFA ruminant nutritionist. “Don’t change feed too abruptly. It takes time for the rumen to adjust to a new ration.”

How long should a cow be dry? This has been argued for at least 200 years; the tradition says a 60-day vacation is optimum.

“But that 60 days is not carved in stone. There is new evidence that shorter dry periods may be better. For some cows—those with huge udders and cows subject to milk fever—no dry period may be the best option,” said Dr. Jardon.

Shortening the dry period can have several advantages, he pointed out: It makes for easier transition, with fewer health problems; better reproduction rates; fewer group changes and the elimination of separate facilities for far-off dry cows; and fewer ration changes with more consistent diets.

“And cows with no dry period generally eat better after calving,” Jardon said. “However, I’m not ready to recommend zero days dry period, except in some circumstances.”

There are differing theories on how to feed dry cows, too, especially when it comes to energy versus fiber. “A cow’s appetite wanes in late gestation,” noted Dr. Jardon. “For one thing, the growing fetus begins to crowd the rumen. The challenge is to get dry matter into her without boosting energy or protein too much. Do not feed milking rations to close-up dry cows.”

With close-to-calving dry cows, low-energy diets (some dairymen feed straw) improve rumen fill, fiber mat and the efficiency of fermentation. This helps prevent “fat cow” type responses to excessive energy consumption.

“You want to control energy, but prevent a drop in DMI in close-up cows,” he said. “A low-energy forage diet is simple to manage and makes for consistent intake. However, do not introduce a high-bulk diet in a pre-fresh group of cows only. Cows require 7 to 10 days to adjust, otherwise DMI will drop. Cows that are not eating well before calving may not eat well after calving.”

Sodium and potassium should be limited in dry cow rations, Dr. Jardon continued. “The ration should have strong fixed cations and anions,” he said. “This causes a slight metabolic acidosis, which allows the main hormone controlling calcium to work better. Hydrochloric acid is a good acidifier and is more palatable (not as bitter) as traditional anionic salts.”

“Use feeds that complement the situation,” said White. “Problems are less expensive to avoid than to correct. Feed a dry-cow ration that equals about 2 percent of the cow’s bodyweight as DMI. We often see cows drop DMI by 30 percent in the last week dry, and can see DMI declines as high as 75 to 80 percent.

“That dictates a ration that is palatable,” White added. “You can feed MFA Rampart at one-half to 1 percent of bodyweight as the concentrate ration, plus 5 to 8 pounds of long forage per day. That provides an anion/cation balance.

“Or, you can feed 5 to 8 pounds per day of MFA Dry Cow Feed or 1.25 pounds of MFA Dry Cow Supplement, both plus Dry Cow Mineral,” he said. “If you’re using a TMR [total mixed ration] as part of the dry-cow feed, don’t feed too much of it. A TMR may be convenient, but it may not be what the cow needs.”

And, don’t overlook basic feeding management, such as: adequate bunk space, clean bunks, fresh feed and adequate fresh water.

“Most bad things happen right after a cow calves,” said Dr. Jardon. “Most of the physiological problems are related to nutrition: milk fever, retained placenta, ketosis and fatty liver, displaced abomasums, rumen acidosis. Milk fever can be a precursor for a lot of other ailments.

About 25 percent of the cows culled leave the herd within 60 days after freshening.”

The cost of fresh cow problems can be considerable, he noted.