S-1000
Regional Project
Animal
Manure and Waste Utilization, Treatment and Nuisance Avoidance for a Sustainable
Agriculture
2003 Station
Reports
Reporting Scientist:
J.P. Fontenot
Location: Virginia Polytechnic Institute and State University
Objective 5
Progress to date
Research to study the relative efficiency of recycling
nutrients in broiler litter by feeding to steers or soil application to pastures
was continued. In 2002, 2679 lb and in 2003, 1187lb of litter per acre
were applied to the pasture, equal to the amount fed to cattle. Generally,
soil P, K, Ca, Zn, and Cu were higher for pastures in which cattle were fed
broiler litter and litter and inorganic fertilizer were applied to the soil.
Over 8 yr there has been a gradual increase in soil P on pastures in which
litter was fed or applied and inorganic fertilizer was applied. Usually daily
gains were lowest for cattle on pastures on which litter was not fed or applied
and inorganic fertilizer was not used. There were no consistent differences
in forage composition. Usually blood serum Cu was highest for cattle
fed broiler litter. The effect of oscillating digestible intake protein
(DIP) levels (60 and 100% of requirements) at 48, 72, and 96h was studied
in growing steers. Daily gains and feed efficiency tended to be highest
for cattle fed oscillating protein at 96 h intervals.
Usefulness of findings
Improvements in utilization of N in cattle would result
in lower excretion of these nutrients. Utilization of poultry litter
by feeding to cattle on pasture may avoid applying excessive amounts to the
soil.
Work planned for next year
Feeding or soil application of poultry litter will be
discontinued and soil P will be monitored for 2 years. Feeding studies
will be conducted concerning methods of lowering dietary levels of N in ruminants.
Publications Kwak, W.S., J.P. Fontenot and J.H. Herbein. 2003.
Digestion and nitrogen utilization by sheep fed diets supplemented with processed
broiler litter. Australian J. Anim. Sci. (in press).
Fontenot, J.P., R.K. Shanklin, D. Fiske, G. Mullins and L. Harlow.
2003. Nutrient management of broiler litter for cattle on pasture.
Proc. Va Tech. Shenandoah Valley Agric. Res. Ext. Center Field Day.
pp 13-15.
Mullins, G.L., J.P. Fontenot, G. A. Alloush, D. G. Boyer and D. P. Belesky
2003. Phosphorus and fecal coliforms in surface runoff from grazed
pastures as affected by nutrient management. Proc. Va Tech. Shenandoah
Valley Agric. Res. Ext. Center Field Day. pp 16-18.