Well-managed pasture is an asset to a dairy farm, poorly managed pasture can create serious problems.
These can include the following:
1. Poor plant growth due to overgrazing damage.
2. Poor animal performance (including poor reproductive performance) and reduced milk production due to:
inadequate dry matter intake (DMI) from pasture or incorrect supplemental feeding.
3. Animal health problems, particularly parasite problems.
This counseling will address some common pasture pitfalls and how they can be assessed.
*Preventing Overgrazing Damage
Overgrazing of pasture plants is likely the most common pasture pitfall on grazing farms. If a plant is grazed while it is still growing from carbohydrate reserves rather than from active photosynthesis, it has been overgrazed.
[url removed, login to view] down all the interior fences in the fall and letting cows "clean up" the pastures.
[url removed, login to view] a "rotational" system of six or seven paddocks, with each grazed for one or two days.
[url removed, login to view] animals in a pasture for more than three days in a row.
[url removed, login to view] animals to the pasture before all of the plants have regrown.
[url removed, login to view] adding additional acres into the grazing rotation when plant growth rates slow.
*Preventing Overgrazing Damage
An important part of MIG(management intensive grazing) is that when pasture growth slows, the speed of the rotation must also slow down. This is usually done by adding more acreage to the rotation.
*Pasture Height and Density Controls DMI (Dry Matter Intake) of Dairy Cows
The best way to make sure cows are eating enough DMI from pasture is to pay close attention to the size of the bite of pasture they receive. Pasture height and density determines this bite size. If the pasture is too short, then they cannot get enough pasture in each bite to meet their DMI needs, even if given a larger area to graze.
If cows are grazing the same pasture for several days or a week, the nutritional quality of what they eat each day will change due to this selective grazing behavior. Using a higher stocking density (smaller paddocks) and moving cows to new pastures more often will result in more predictable pasture nutrient intake, which can make ration balancing and milk production easier to manage.
*Cows will reject some pasture around manure. This natural instinct helps them avoid areas containing parasites.
* What Pre-grazing Height is Best?
The traditional MIG guidelines outline a pre-grazing height of eight inches for dairy cows. Turning cows into pastures which are too short will result in lower dry matter intake and some overgrazing damage to plants. There may be times when it is advantageous to allow pastures to grow even taller than eight inches before grazing, but once plants become too mature, the nutritional quality, palatability, and the ability of cows to get enough dry matter will be reduced.
* Ration Balancing and Pastures
The two most common nutritional pitfalls during the grazing season are feeding too high a protein concentrate, and inadequate dry matter intake (DMI) due to pasture plants being too short.