摘要:Requiring that crop applications of manure be based on phosphorus content (P-standard) could increase poultry litter disposal costs. Microbial phytase reduces litter P content and could reduce litter disposal costs under a P-standard. For a representative Virginia turkey farm, phytase costs $2,500 and could increase value of litter used for fertilizer on the turkey farm by $390 and reduce supplemental P feed costs by $1,431. Based on assumed litter demand and supply, estimated litter export prices with phytase could exceed export prices without phytase by $3.81 per ton. Phytase net returns to the farm are an estimated $ 1,435.