A low-energy, chopped straw ration during the early dry period is a good strategy to offset excessive NEFA levels later on in the dry period.
The selection of entrées on a restaurant menu often changes. Some entrées exit, while new ones find their way into the lineup.
The same is true with the menu options available to your transition cows.
During the past 15 years, steam-up diets containing increased levels of concentrates have been popular menu items for cows during the last few weeks before calving. So, too, has the “all-you-can-eat” option, which encourages maximum feed intake. Problem is, these strategies don’t always work on-farm, and many producers still find themselves with pre-fresh cows that suffer huge drops in intake.
As a result, cows dip into their body-fat reserves to meet energy needs and non-esterified fatty acids (NEFAs) soar. Research shows these excessive NEFA levels are linked to a variety of fresh-cow problems. (For more details, please see “An early-warning system”)
Perplexed that these feeding strategies don’t always work, transition-cow researchers have gone back to the drawing board. Although still a work in progress, their findings have produced several new menu options that are proving to be helpful at keeping transition cows eating and NEFA levels under control.
Here’s a look at two recent additions to the dry-cow menu and how to use these diets to maintain pre-fresh feed intake and minimize NEFA levels.
1. Lighten up on energy in far-off diets.
In order to keep pre-fresh NEFA levels under control, start during the far-off dry period.
Feed a low-energy diet — 0.57 to 0.61 Mcal of net energy-lactation (NEL) per pound of dry matter -— during the early dry period, says Jim Drackley, dairy nutritionist at the University of Illinois.
A popular way to accomplish this is to add chopped straw to the TMR at the rate of 20 percent to 30 percent of ration dry matter. That equates to about 5 to 10 pounds of chopped straw per head per day.
Low-quality hay can work as long as ration particle size is adequate, Drackley says. Just make sure to chop the hay to the same length as the straw — about 2 inches in length — before adding it to the TMR. (For more details on incorporating straw into the ration, please see “Tips for adding straw to far-off diets” at right.)
However, do not revert back to the “old-school” idea of feeding free-choice, poor-quality forages in order to achieve a low-energy diet. In addition, don’t restrict feed intake as a way to reduce ration energy density. This approach is not practical in a free-stall setting, as some cows will over-eat while others won’t get enough to eat.
2. Keep close-up intake consistent.
In the past, a successful close-up period has been defined as one where cows maximize feed intake. If intake doesn’t drop off as calving approaches, a cow draws less from her body-fat stores and thus avoids excessive NEFA release and subsequent health problems. In theory, this concept makes perfect sense. In practice, it doesn’t always yield the intended results. All too often, high intakes plunge as calving approaches.
That has led researchers to explore a new theory — one that focuses more on keeping feed intake consistent, rather than maximizing the amount of feed cows eat as calving nears.
This is where high-forage diets can help, says Ric Grummer, dairy nutritionist at the University of Wisconsin.
Typically, a close-up ration contains a 65:35 forage-to-concentrate ratio, 35 percent to 40 percent neutral detergent fiber and 0.73 to 0.74 Mcal NEL per pound of dry matter. To help keep intake more consistent, bump up the forage-to-concentrate ratio to 80:20, Grummer says. This achieves a diet closer to 40 percent to 45 percent NDF and 0.67 to 0.68 Mcal of NEL. This type of diet may contain 10 percent to 15 percent straw, he adds.
However, don’t make the mistake of limiting the amount of feed offered as a way to achieve a more consistent intake. This does not work in a group setting.
Putting it all together
Remember, feeding strategies alone are not a magic bullet for minimizing high NEFA levels during the close-up period. They are just one part of the overall nutrition and cow management strategies that must be used to achieve transition-cow success and minimize the effects of NEFAs on fresh-cow health.
How much intake is enough?
when it comes to determining how much feed to place in front of close-up cows, don’t get hung up on the number. If you’re struggling to keep intakes high, then focus more on minimizing intake suppression instead.
Research indicates “it may be better to have a slightly lower dry matter intake that is held more constant than a very high dry matter intake that falls off more sharply before calving,” says Jim Drackley, dairy nutritionist at the University of Illinois.
That’s not to say you should strive for low feed intake all the time. “If I had to choose between consistent, high feed intake or consistent, low feed intake, I would choose the former,” adds Ric Grummer, dairy nutritionist at the University of Wisconsin. The key to success is to keep that intake consistent.
Tips for adding straw to far-off diets
Use these recommendations from the university of illinois to help you incorporate straw into the far-off dry-cow diet:
The type of straw doesn’t seem to matter, but wheat straw is most popular, followed by barley straw.
Choose straw that is clean, dry and free of mold.
Pre-chop the straw in a forage harvester or tub grinder prior to adding it to the TMR.
To minimize sorting, chop straw to a particle length of about 2 inches or less.
Give cows at least one week to 10 days to adapt to the bulkier diet. Feed intake may decline during this time. For this reason, don’t feed a high-straw close-up diet without having far-off cows on a similar high-straw ration.
If the ration is not consistent, or if sorting or reduced intake is a problem, try adding water to the TMR.