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Planning the Dairy Feed Supply

Timothy R. Johnson, Ph.D. Purdue Dairy Specialist

With softening prices for milk and high purchased feed costs, dairy producers are striving to fine tune their feeding programs to maximize profitability. Good cows can still make money if they are comfortable, well managed, and costs are controlled. There are two major areas that need special attention in planning for feed supply needs this year: 1) how to feed cows on a short forage supply; and 2) how to cope with the relatively high cost of purchased forage and energy feeds.

Short Forage Supplies

Weather conditions and temperatures during peak growth and harvest periods in spring and summer often result in delayed harvest, low-quality forage, and in low yields of hay and hay crop silage. Under these conditions, it is a challenge to producers and nutritionists to carefully plan winter feeding programs and to budget feed supplies.

To deal with this challenge, dairymen may increase corn silage feeding, purchase hay, and attempt to decrease the amount of hay and silage needed by substituting high fiber by-product feeds for forage. Matching expected feed needs and inventories is essential to finding the right combination of these methods, and to budgeting feed costs. As an example, feeding more corn silage reduces the amount of hay required. It can help minimize the purchase of corn, but requires

that more protein supplement be fed as corn silage replaces hay in the feed mix. It also requires that adequate amounts of corn silage are available to extend the ration through the summer.

Work at the USDA Dairy Forage Research Center, Madison, Wisconsin has shown that corn silage can support high feed intake and maintain good production through the full lactation. In the Wisconsin study, rations with 0%, 33%, or 66% corn silage were fed with the rest of the forage dry matter coming from good quality alfalfa silage. The grain portion of the rations was made up of high moisture ear corn, soybean meal, porcine meat and bone meal, and roasted soybeans. Increasing amounts of protein supplement were needed to balance the rations as more corn silage was added. Cows fed two-thirds corn silage maintained similar feed intake and milk production to those fed one-third corn silage. In addition they had greater feed intake and milk protein yield than those cows feed all the forage dry matter as alfalfa silage. The average dairy farm in Indiana typically feeds corn silage as 50% of the forage dry matter. During years of low hay availability, many herds may feed much more than this amount.

Feeding high fiber by-products such as corn gluten feed, dried distillers grain, whole cotton seed, dried beet pulp or soybean hulls can both serve to replace forage and add additional protein to high corn silage rations. An additional benefit to feeding these by-products is that they can offset the extremely high moisture content of corn silage based rations. Many by-product feeds contain considerably more phosphorus than the hay or corn silage they replace. Adjusting mineral supplements by reducing or eliminating added mineral phosphorus reduces feed

cost and helps protect the environment by reducing excretion of undigested phosphorus in the manure.

Routine forage testing on a monthly basis, and whenever feed sources change, will be particularly important during times of by-product feeding. Forage tests are an inexpensive management tool to use to update formulation of rations. Results from these tests become even more important in years of short forage supply.

Consider the cost of, and storage requirements for by-products, and see your county Extension Educator or feed professional for suggested combinations of available by-product feeds.

Feed Budgeting

Budget planning for both total feed and storage capacity needed is required to determine feed needs for the current season and the upcoming year.

The first step in planning a feed budget is to calculate expected forage and grain needs for the milking herd and replacement stock. Rough estimates of forage and grain needed per cow at different production levels is shown in Table 1 on a per cow or per heifer basis for a 365 day feeding period.

The second step is knowing the inventory of forages currently on the farm and calculation of the available storage space for corn, corn silage, haylage and hay. To calculate available storage space for grain crops and forages, see detailed feed

storage structure capacity charts in Midwest Plan Service Dairy Housing and Equipment Handbook (MWPS-7). A brief table estimating the amount of hay in mows or silage in horizontal silos is presented in Table 2.

The feeding program is the third step in planning a feed budget. Forage is the base of the feeding program, and determining the proportion of hay and corn silage that will be fed is one of the critical decisions that must be made. Nutritionists, feed company personnel, Extension Educators, the producerÕs personal experience, and the planning tools discussed in points mentioned above, can all help in making feeding decisions.

Producers may also start by determining whether corn silage inventories are adequate to get to the next harvest. At typical intakes of 65 lbs. of corn silage as feed, a three-week delay in harvest requires an additional 68 tons of corn silage for a 100-cow herd. Planned inventory overages are often underestimated during herd expansions.

There are many alternatives to stretching inventories. Among those is purchasing additional alfalfa hay locally or from Western U.S. sources, adding commodity feeds to the ration where affordable, and considering planting of alternative forage crops for earlier harvest. A mid-May seeding of cool-season annual crops like spring oats or spring triticale, seeding warm-season annual grasses, such as brown midrib sorghum-sudangrass or pearl millet and use of soybeans or soybean-field pea mixtures in combination with sorghum-sudangrass may play a role in extending supplies of other feeds. Selection of shorter season

corn and hybrids will help speed the next yearÕs corn silage harvest, but may come at some expense in tonnage yield per acre.

When planning corn silage inventories, dairy producers are reminded to plan a three-week supply of last seasonÕs corn silage to feed while the newly harvested corn silage ferments. Even if this cannot be done this year, plan this year to reserve a supply for future harvest seasons. Many producers simply place a three-week supply in silage bags or an upright silo that can be fed while the bunkers or other upright silos are filled and ferment. An ounce of prevention is worth a pound of cure; your cows will appreciate the planning.

While we can never predict exactly what crop yields or weather conditions will be, getting a head start on planning the feeding program and needed supplies of harvested feeds can help to \"pave the road\" to higher profits in dairying for the coming year.

1 - Values given are for DM needed/animal/365 days. This includes a dry period of 60 days for milking cows fed about 28 lb DM hay/day. A reasonable estimate of DM consumed can be obtained from the equation DM intake = (2 + (.02 X milk lb/day)) X cwt body wt. This does not include feeding and storage losses which are included in the above table. The value from that equation can be used for any given period. That value can then be multiplied by the percent concentrate and forage in the ration (DM basis) to give lb DM of each needed for that period.

2 - Forage values are in tons of dry matter. To convert to as fed basis divide lb or ton hay DM by .87; to convert DM to lb or ton of 55% DM haylage, divide lb DM by .55; to convert DM to ton or lb of 35% DM silage divide by .35.

3 - Grain values are total DM for 1 yr. A 12% grain mix requires 90% corn and 10% soybean meal (44% protein SBM) or equivalent; a 14% requires 15% SBM; 16% requires 20% SBM; and 18% requires 26% SBM or equivalent. To convert lb corn DM to lb of HM corn as fed divide lb DM obtained from table and footnote 3 by % DM in the HM corn; i.e. the cow needs 4000 lb dry corn plus 2000 lb SBM. Amount of HM corn is 4000 ) 0.70 (70% DM in HMSC) = 5714 lb of HMSC. Source: Midwest Plan Service Dairy Housing and Equipment Handbook (MWPS-7); and E-1821 Dairy Farm Analysis Workbook, 1985. Michigan State University

Estimating Feed Supplies in Bulk

1. To find the number of bushels of grain or shelled corn in a bin: Multiply the length by the width by the depth (all in feet) and multiply by .80.

2. To find the number of bushels of ear corn in a crib: (This is the ear corn equivalent of shelled corn or a double bushel.) Multiply the length by the width by the average depth (all in feet) and multiply by .40. If the crib is round, multiply the distance around the crib by the diameter, by the depth (all in feet) and divide by 10.

3. To find the number of tons of hay in a mow or silage in a horizontal silo: Multiply the length by the width by the height (all in feet) and divide by the cubic feet required per ton. Use the average width of trench or bunker silos in these computations (top width plus bottom width divided by 2). If the number of bales of hay is known, multiply by the average weight and divide by 2,000 pounds.

4. To determine the weight of feed or grain in a bin: Multiply the length by the width by the height and multiply by pounds per cubic foot for the feed or grain being measured.