Is it time to ditch the negative DCAD pre-fresh ration?April 27, 2017 3:07 pm
Anywhere from 50 – 80% of dairy herds in North America are utilizing the negative DCAD pre-fresh ration to some extent. But why?
Research shows that the cows are still experiencing subclinical hypocalcemia at calving. This is also the case when practicing the negative DCAD approach under University conditions.
The above study/graph shows that a properly managed negative DCAD pre-fresh ration will likely eliminate clinical cases of hypocalcemia. However, this is only the tip of the iceberg.
With recent studies proving that subclinical hypocalcemia is at least four times as costly as clinical cases (as found by Oetzel and illustrated by Hoards here), we ask the question, why are we still using methods that don’t eliminate hypocalcemia entirely?
Acidifying the diet to acidify the blood, is not a natural “thing” for the cow. Additionally, it induces acidosis in the rumen and may even be harmful to the cow and the calf in the long run.
Here’s some food for thought,
- Could it have an influence on her longevity?
- How does it affect the colostrum quality?
- It’s labor intensive and requires constant measuring of pH.
- Lower quality forages due to the need for balancing (potassium).
Let’s talk about the low calcium approach instead.
The low calcium approach has been recognized as the most efficient way to eliminate subclinical hypocalcemia in transition cows.
However, until now it has been difficult to get the available calcium level below 20 grams per day per cow for her to trigger the PTH.
Getting the cow below 20 grams of daily calcium intake can now be accomplished by using a calcium binder; X-Zelit.
By adding X-Zelit (calcium binder) to the ration the last 14-21 days, pre-fresh, the cows are depleted of Ca in the small intestine. This method triggers the cow’s natural defense mechanism (PTH) to mobilize Ca from body reserves into the blood.
This method of prevention is a natural process for cows, unlike the negative DCAD.