|
|
|
|
|
|
|
| Consider management factors before altering dairy nutrition |
|
|
|
With feed costs very high, dairy farmers continue to seek ways to economize. Ohio State University Extension Dairy Specialists Bill Weiss and Maurice Eastridge wrote a Dairy Industry Brief (DIBS) in December 2010, titled “Can I reduce costs by ‘limit-feeding’ heifers?”
A dairy farm that replaces 30 percent of its lactating herd annually with heifers that calve at 24 months of age needs approximately 67 replacements per 100 cows to maintain a stable herd size. Assuming typical diets for the various growth stages, the cost to feed a heifer from birth until calving is approximately $1,000. That suggests a good quality milk replacer was used and that stored forages such as hay and silage, rather than pasture, were fed. The heifer rearing strategy used by most Ohio dairy farmers consists of feeding weaned heifers a high quality, concentrate based diet until they are 4 to 6 months old and then switching to a high forage diet with limited concentrate. This diet is fed free choice and the amount of concentrate is altered to maintain the desired rate of growth (approximately 1.8 pounds per day). Dry matter intake of Holstein heifers averaged over 5 to 24 months of age is about 18 pounds per day.
A relatively new method of raising heifers is to provide enough nutrients to meet their requirements and grow at 1.8 pounds per day by feeding a limited amount of a nutrient dense diet, rather than allowing high intakes of less nutrient dense diets. Dry matter intake of limit-fed heifers is generally about 20 percent less (average about 14 pounds per day), but the diet must have more usable energy and protein per pound than a conventional diet, thus much higher in concentrate ingredients and lower in forage.
These diets are typically 25 to 40 percent forage, with the remainder being corn, oilseed meal, and some inexpensive byproducts such as distillers grains and wheat middlings. Also, one of the reasons for using limit feeding of heifers is when using corn silage as the primary forage in the diet.
With a limit feeding program (approximately 3 to 5 pounds per day more concentrate will be fed) and the daily cost of that concentrate will be substantially greater ($0.25 to $0.40 per day more) than with a typical heifer raising system. When forage is very cheap and concentrate costs are at current market prices, feed costs for conventional and limit feeding are generally equal, or less for the conventional system. However, when forage is more realistically priced, limit feeding may save as much as $0.10 per head per day.
A major factor in determining whether limit feeding will save money is the value you place on the forage. If heifers are pastured on land that has few or no alternative uses, then limit feeding a high concentrate diet will probably increase feed costs compared to utilizing the pasture. To be successful with limit feeding, adequate feed bunk space is absolutely essential. If additional facilities are needed to house heifers so that adequate bunk space is available, any savings in feed costs may be lost.
More labor (and management time) may be needed to monitor growth of the animals to ensure adequate energy and protein is being provided, and for pushing up feed in the bunk so it can be reached by the animals. Also, other changes in animal behavior may occur and should be monitored, e.g. increased bellowing prior to feeding, especially during the first week of switching to limit feeding.
Bottom Line – Providing a limited amount of a more nutrient-dense diet increases the cost per pound of diet, but because substantially fewer pounds are fed, feed costs may be reduced. However, before adopting a limit-feeding regime for heifers, consider all the management factors involved. |
| 1/14/2011 |
|
|
|
|
