Broiler and Turkey Litter as Protein Supplements for Growing Steers
With the expansion of both the broiler and turkey industries in North Carolina, a large supply of both types of litter have been generated and must be disposed of in an environmentally friendly manner. Both of these products offer potential as nitrogen and mineral sources for feeding cattle. Broiler litter has been used successfully as a feed source for both growing cattle and brood cows. However, very little research is available for evaluating turkey litter in feeding programs.
Materials and Methods
Six feeding trials (three with broiler litter and three with turkey litter) involving 384 growing cattle have been completed. In all of these trials, litter containing from 20 to 30% protein has been obtained from either broiler or turkey houses and deep stacked under plastic for approximately 60 days prior to feeding. The litter has then been top-dressed over corn silage and mixed with the silage at the time of feeding. In all trials, steer of heifer calves, weighing approximately 400 lb initially, were purchased approximately 60 days prior to initiating the studies. Animals were housed in a confinement feeding facility consisting of 16 pens of four animals each. In all trials, four replicate pens were used in evaluating supplemental treatments (16 animals/treatment) and animals were assigned to pens based on body weight.
Summary of Results
Three trials in which broiler litter was used to provide all the supplemental protein to corn silage based diets resulted in average daily gains of 1.97 lb/day as compared to 2.28 lb/day for similar animals supplemented with soybean meal. The improvement in gain for the soybean meal supplement for the three trials was .27, .26 and .39 lb/day. When broiler litter was used to provide 50% of the supplemental protein and either soybean meal or ring dried blood meal was used to provide the remaining 50%, performance was equal to animals fed soybean meal. These results confirm that broiler litter is a satisfactory and economical nitrogen source for growing cattle.
Three trials in which turkey litter was used to provide all the supplemental protein to corn silage based diets resulted in average gains of 1.62 lb/day as compared to 2.41 lb/day for similar animals supplemented with soybean or cottonseed meal. The improvement in gain of the soybean or cottonseed meal supplemented cattle was 1.12, .76 and .48 lb/.day for the three trials. In two of the trials, graded levels of turkey litter (0, 33.3, 67.7 or 100%) were used to supply the supplemental protein and soybean meal the remainder. In both trials, a linear depression in gain was observed as the level of turkey litter was increased in the diet although very little if any, depression was observed at the low level of turkey litter compared to animals supplemented with soybean meal. In the trials with turkey litter, serum minerals and ruminal ammonia nitrogen were examined and were in the normal range and did not appear to be the reason for the depressed gains. Based on the results of these trials, turkey litter should not be used to provide more than 33.3% of the supplemental protein for growing cattle fed corn silage diets.
Source: R. W. Harvey, J. W. Spears and M. H. Poore in http://www.cals.ncsu.edu
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