Poultry Nutrient Management
Through Livestock Feedstuffs
Feeding Broiler Litter to Beef Cattle
A unique digestive system allows cattle to use waste and by-products as dietary nutrients. The cattle industry is built largely on the use of by-products and other materials that can be digested only by ruminants. Broiler litter is one by-product that can be used as a cattle feed.
Nutritional Value of Broiler Litter
Broiler house bedding materials include pine wood shavings, pine sawdust, and rice hulls. Rice hulls sharp points can irritate the digestive tract; therefore, take care when feeding poultry litter containing rice hulls. Poultry house owners use varying amounts of these products for the initial bedding and as additional bedding after each batch of birds. The bedding material alone is a low-quality feed ingredient. However, with the addition of feathers, waste feed, and excrement from the birds, the nutrient quality of the litter improves.
The kind of broiler house bedding material has little effect on the quality of the litter when it is used for cattle feed. Because the amount of bedding used and the number of batches of birds housed on the litter are not standardized or regulated, litter quality varies considerably from one producer to another. Other factors such as broiler house management, the method of litter removal, and moisture content can add to the variation in litter composition and quality.
Watering system management determines the amount of moisture in broiler litter. Moisture content does not vary significantly between fresh litter and litter stacked for 6 months or more. Though moisture content is not an important measure of nutrient value, it will determine the physical quality of the feed. A feed mix with more than 25 percent moisture content will not flow easily through an auger. However, if the broiler litter is 12 percent moisture or less, the ration may be dusty and less palatable to the cows.
Total Digestible Nutrients
The total digestible nutrient (TDN) figure is calculated from crude protein and crude fiber values. The energy value of broiler litter is fairly low in comparison to grain. However, litter with 50 percent TDN is comparable to poor-to-fair quality hay. Litter could be a source of energy for both stocker cattle and brood cows.
Broiler litter averages 24 percent crude protein and can range from 15 to 38 percent. More than 40 percent of the crude protein in litter can be in the form of nonprotein nitrogen. The nonprotein nitrogen is mostly uric acid, which is excreted by poultry. Young ruminants do not use nonprotein nitrogen as readily as more mature beef cattle. So, for best performance, feed broiler litter to beef cattle weighing more than 450 pounds.
Cattle have trouble digesting feed containing bound (insoluble) nitrogen. This element becomes insoluble when ingredients overheat. Bound nitrogen averages about 15 percent of the total nitrogen. In litter that showed signs of overheating, more than 50 percent of the total nitrogen can be bound.
As the amount of bound nitrogen increases, dry matter digestibility decreases. Thus, overheating significantly reduces the feeding value of the litter.
Broiler litter has an average 24 percent crude fiber content, mainly from chicken bedding materials such as pine shavings and sawdust, and rice hulls. Bedding usually consists of finely ground, short fiber materials. The fiber in litter cannot effectively meet the ruminants need for fiber, because cattle also need long roughage to maintain their digestive systems properly. Cattle that are fed litter will naturally crave and readily consume long roughage. Even though litter fiber content is high, it is recommended that a minimum of 5 percent of the ration be in the form of long hay or roughage.
Broiler litter is an excellent source of minerals. Brood cows fed a diet of 80 percent litter and 20 percent grain will consume five times more calcium, phosphorus, and potassium than required. The excess minerals are not a problem except under specific conditions.
The 2 percent calcium level, in the presence of an imbalance of other minerals, can cause milk fever in beef cows at calving. This risk can be reduced by removing brood cows from a litter ration before calving or by providing at least half of their feed as hay or other roughage. It is not known exactly how many days before calving a cow should be removed from litter. However, based on milk fever studies with dairy cattle, 30 days should be adequate. Milk fever may be a problem with a small number of cows after parturition. Therefore, brood cows consuming broiler litter at calving should be checked often.
Ash content is one of the important measures of the quality of litter. It is made of minerals from feed, broiler excrement, bedding material, and soil. Ash contents of more than 28 percent are too high and should not be fed to beef cattle.
Calcium, phosphorus, potassium, and trace minerals make up about 12 percent of the ash in broiler litter; the remaining ash is soil. Take care to keep the ash content, especially the soil percentage, as low as possible if the litter is to be used for cattle feed. Most soil enters litter during removal from the broiler house and during loading on trucks for transportation.
Processing and Storing Broiler Litter
Broiler litter, like any other feed ingredient, holds potential hazards. Many common feed ingredients can be affected by pesticide residues, mycotoxins such as aflatoxin, and even nitrate toxicity. Other potential hazards are associated with pathogenic bacteria, such as Salmonella, and residues from medicated poultry rations, such as antibiotics, coccidiostats, copper, and arsenic. All litter, regardless of its source, should be processed to eliminate disease-causing organisms.
The most practical method of processing litter is deep stacking. The stack will heat to 130 °F or higher within 5 days. To eliminate Salmonella and other potential pathogens, keep the litter deep stacked for at least 20 days.
The common nitrogen compounds uric acid and urea degrade to ammonia which also kills pathogenic organisms. At 140 °F, bacteria such as Salmonella, tubercule bacilli (associated with avian and bovine tuberculosis), and pathogens excreted with feces are killed within an hour. There is no risk of transmitting diseases through feeding litter if it has been deep stacked for 20 days or more, and if the stack has reached an internal temperature of 130 °F or more.
Heat is the one thing that reduces the quality of broiler litter in the stack. Excessive heating reduces dry matter digestibility. Fresh stacked litter heats spontaneously.
To control excessive heating (more than 140 °F), limit the moisture content of the litter to less than 25 percent, and limit the litters exposure to air. Sealing the broiler litter stack with 6 mil polyethylene to exclude oxygen is the least expensive method of heat control. Use polyethylene if the stack is under a barn or if it is outside. If the temperature is 160 °F or more, the protein becomes bound, and digestibility decreases.
Because the nutrient
levels in broiler litter vary, suggested rations should be used only as
In Table 1, Ration 1 is calculated for use as the major ration for dry beef cows until 3 to 4 weeks before calving. Provide hay or some other roughage to maintain normal rumen function. At least 2 pounds daily of long hay should be adequate. A 1,000-pound dry cow requires 20 to 24 pounds of Ration 1 during the winter months for maintenance. Corn that is mixed with broiler litter should be cracked or ground. Cattle that are fed mixtures of litter and whole grain corn or other grains tend to waste more feed than when fed ground grain mixtures.
The lactating brood cow needs Ration 2. Fed at about 25 pounds daily, this ration furnishes enough nutrients during the winter. The lactating brood cow and the dry cow will need some long hay or roughage for normal rumen function.
Ration 3 is formulated for growing stocker cattle. Stocker cattle weighing 500 pounds will consume about 3 percent of their body weight of this ration. Healthy stocker cattle that have been wormed, vaccinated, implanted, and otherwise managed as recommended should gain an average of 2 pounds daily when fed this ration.
Total gain has improved by feeding Ration 3 to stockers during conditioning and during the typical winter deficit grazing period. Also, stocking rates can be increased and rates of gain maintained by feeding the ration free-choice on winter grazing crops. Stockering cattle on summer pasture alone has produced only one pound daily gain. Providing Ration 3 free-choice increased the rate of gain to more than 2 pounds daily and increased the total pounds of beef produced.
Since only about one third of the broiler litter presently produced is high enough in quality to be beef cattle feed, all litter that is fed should be tested for nutrient content. Beef producers should use broiler litter that is at least 18 percent crude protein and is less than 28 percent ash. Not more than 25 percent of the crude protein should be bound or insoluble. Although other nutrient levels are important, these are the most critical measures of quality.
Growing Forages With Poultry Litter
Poultry litter, properly handled, is the most valuable of all manures produced by livestock. Regardless of species, forage feeding value is largely determined by its stage of maturity when grazed or harvested. Young, leafy vegetative growth has a higher level of digestive nutrients and protein. Older forage has fewer leaves, more stems, and a higher fiber content. Seedhead development indicates maturity and decreased quality.
Litter Application Rates
Litter management in Mississippi has been based on phosphorous requirements of growing crops. Most other states used nitrogen-based nutrient management planning. Recent nutrient management planning refinements include a risk analysis tool, the Phosphorous Index, to determine site-specific plans for Mississippi farms. It is anticipated that most plans in the state will be nitrogen-based.
For example, 80 pounds of nitrogen per acre is recommended for hybrid bermudagrass (table 2). If one ton of litter contains 60 pounds of available nitrogen, then 1.3 tons should be applied per acre. This will not meet the phosphorus and potassium requirements if these nutrients are very low in the soil, but generally these are not totally deficient in Mississippi soils. If hybrid bermudagrass pastures are cut for hay, 10 to 12 pounds of phosphate and 40 to 50 pounds of potash can be removed per ton of hay harvested. There will be only 3 pounds of phosphorus and one pound of potassium removed by a 500-pound calf, so these nutrients will tend to build in a cow-calf situation.
Application Rate Checks
Be sure you know the rate of litter being applied by calibrating spreading equipment. A drop cloth used to collect and weigh litter that is spread on the field is a quick way to estimate application rate.
Estimated value per pound of nutrient is based on current retail cost for ammonium nitrate (34-0-0), concentrated superphosphate (0-40-0), and muriate of potash (0-0-60):
Using an average fertilizer grade of 4-2-3, a reasonable value of available nutrients would be about $31.50 per ton.
If the forage is grazed, and if we assume that it takes 15 pounds of dry matter to produce a pound of beef gain, then an extra 500 pounds of forage would produce an added 33 pounds of beef per acre. With beef worth only 70 cents per pound, the extra gain would generate about $23.10 per acre. This reduces the cost of nutrients (one ton litter) to fertilize an acre of forage to $8.40.
Research data from Texas, Alabama, Georgia, Mississippi, and Louisiana indicate 50 to 100 pounds of nitrogen per acre will increase forage production of common bermuda, coastal bermuda, and bahiagrass by an average range of one to 2 tons, depending on the species. This is an excellent return per ton of litter applied, indicating that when litter is used correctly, it is a valuable source of nutrients.
By Blair McKinley, Associate Extension Specialist - Beef Management; Dr. Malcolm Broome, Assistant Extension Specialist - Forages; Dr. Larry Oldham, Extension Agronomy Specialist - Soils.
Copyright 2000 by Mississippi State University. All rights reserved.
This document may be copied and distributed for nonprofit educational purposes provided that credit is given to the Mississippi State University Extension Service.