20 November 2012

5 minute read

Drought silage for growing cattle. Drought silage can be an excellent feed. After testing to assure that the product is safe for feeding relative to nitrate content, diets of predominantly silage can produce daily gains of 2.0-2.5+ pounds per day. The product will require supplementation for protein and minerals. Backgrounding could continue for as few as 60-70 days, or up to 1,000 pounds or more depending on the amount to feed and the need to ration corn in the feeding programme.

A minimum of 70-80 days on a high-energy ration will be required for cattle to produce acceptable carcass quality in normal market channels. This new fact sheet from IBC provides information on how to use drought silage in your growing cattle diets www.iowabeefcenter.org/information/droughtsilageuse.pdf



Off-quality corn. Early indications are that grain quality may be quite variable with the corn crop across the Midwest this year. Aflatoxin and low test weights can become an issue in drought years. These anti-quality factors and be a curse for grain marketers, but an opportunity for cattle feeders. Aflatoxin is caused by the fungus Aspergillus which tends to thrive in drought stress.

The effects on animals vary from liver damage, reproductive effects, reduced growth and immunity to death. Generally, finishing beef cattle are more tolerant of high levels of aflatoxin than other species. Research is somewhat variable on production effects of levels of aflatoxin. The FDA has established action limits of aflatoxin in grain for commerce. These levels should be considered quite safe feeding levels as well.

The FDA action level for feed is 20 ppb. The exceptions are corn for breeding cattle, breeding swine and mature poultry (100 ppb), corn for finishing swine (200 ppb) and finishing beef cattle (300 ppb). Milking dairy cows cannot be fed feed greater than 20 ppb as aflatoxin can be transferred to milk, and the action level for fluid milk is .5 ppb.

Low test weight corn, if purchased at a discount, can represent an opportunity for feedlots to lower their feed costs. Corn with test weights as low as 45 lb. was either similar to, slightly better or slightly poorer than normal (55-58 lb./bu.) corn in three feeding trials. However corn under 40 pound test weights did show a reduction in efficiency of 9 per cent when fed at 80 per cent of the diet in a North Dakota State Study, when compared to normal corn.

Alternative grains. Feed grains other than corn also can be used for finishing cattle if the opportunity arises. Sorghum, wheat, barley, oats -- all can substitute for a significant portion of corn if priced competitively. Wheat is similar to corn in energy value and higher in protein. Wheat is rapidly fermented in the rumen and can be an acidosis risk if not properly managed.

It is recommended to limit wheat to 30-40 per cent of the ration because of this. Barley is excellent feed grain that can replace corn. It is also higher in protein and contains 90-95 per cent of the energy of corn. Barley is the feed grain of choice in Western Canada. Sorghum grain (milo) contains approximately 90 per cent of the energy of corn grain.

Sorghum responds well to processing including fine grinding and steam flaking, which both improve its feeding value relative to corn. Oats are lower in energy (85 per cent of corn), which will limit their use in finishing rations. Oats can be the primary grain in a backgrounding ration if available at a competitive cost.

Commodity feeds. Soy hulls, wheat midds, hominy feed, whole cottonseed, oat byproduct, bakery byproducts all can be sources of energy for beef cattle.

These commodity feeds quickly adjust in price due to market demands but occasionally can be priced competitively into beef rations. Corn processing co-products such as distillers dried grains; modified distillers grains, wet distillers grains, condensed distillers solubles and both wet and dry corn gluten feed have become among the lowest cost feedstuffs available to Iowa cattle producers over the past 5 years.

Many are concerned about the availability and price of these feeds as ethanol plants reduce their production. It should be noted that given the size of the ethanol industry even at half production these feeds are still among the most abundant commodity feeds available. That does not mean that spot shortages or unfavorable pricing may not exist, however. The best advice relative to these feeds is to stay alert for opportunities and take advantage of them when they occur.

Protein sources. If distillers grains and other corn co-products become priced such that they are no longer the lowest cost energy source compared to grains or other byproducts, then they will become sources of protein for beef cattle.

Rather than feedlot rations that are 30 or 40 per cent distillers grains, levels of 15-20 per cent would likely meet this requirement. It is possible that the traditional sources of protein, soybean meal and urea will once again be lower in cost per unit of protein than distillers grains. Soybean based 32-36 per cent protein supplements will be the likely source of complete supplements that utilize soybean meal.

Urea based supplement will be non-protein nitrogen containing commercial supplements or liquid supplements, typically. Be sure and balance rations using metabolizable protein with incorporating urea into rations. The Beef Ration and Nutrition Decision Software (BRANDS) form the Iowa Beef Center can account for this.

Cattle are adaptable animals and there are many feed choices that can work. Producers are encouraged to evaluate all opportunities. Unfortunately when prices are high for corn and hay, prices are also high for most other feeds. The best program for any one producer will be very individualized and depend on local opportunities.