A natural fertilizer for crops may have less benefit than thought.
Cow manure has been used as a fertilizer for decades but a joint study by the Colorado State University and Idaho University found some disturbing results in use of cow manure fertilizer.
Numerous effects were found from manure that came out of cows injected with antibiotics.
This manure altered microbial activity in the soil, soil respiration and ecosystem function.
The plants changed the way they spread carbon below ground and take up nitrogen.
The upshot: when cow manure with antibiotic residue is used as fertilizer less carbon is stored and more carbon is released by plants.
Lead author Carl Wepking of Colorado State University said no environment on earth is free from antibiotics.
Eighty per cent of antibiotics used in the United States are used on livestock.
The research reviewed fertilizer effects of cow manure from animals given antibiotics and animals that didn’t receive antibiotics.
Studies before this injected cow manure with antibiotics.
Wepking said more research is needed but cow manure fertilizer users may want to re-think the process.
