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A New Crop for Dairy Producers??

Dairy Pipeline: September 2000

Ernest Hovingh
Extension Dairy Veterinarian
Virginia-Maryland Regional College of Veterinary Medicine
Virginia Tech
(540) 231-5234

The July 2000 issue of the Agricultural Research Magazine (published by the USDA: reports that researchers at the Agricultural Research Service are investigating how effective algae will be at removing phosphorus, ammonia, and nitrate from liquid manure. The system has been adapted from one that is used to remove fish waste from water, and microbiologist Walter Mulbry reports that in the laboratory the "...system eliminates almost all losses of ammonia and nitrate as well as most, if not all, phosphorus losses." The current tests are evaluating the system in the dairy barns at the USDA research center in Maryland. Plans are to harvest the algae weekly from the screens on which it will be growing. It is hoped that the algae can be dried and made into fertilizer or high-protein livestock or fish feed. Feeding trials are planned to evaluate its nutritional value. No mention is made in the report of whether or not the algae can help to control odors associated with liquid manure systems. Nutrient reclamation or recycling systems such as this may play an important and necessary role in waste management on dairy farms. If this research is able to demonstrate that this is a feasible approach it could be of significant interest to the dairy industry!

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