UNIVERSITY PARK, Pa. — The optimum amount of a methane-inhibiting supplement in dairy cattle feed has been determined by an international team of researchers, indicating that widespread use of the compound could be an affordable climate change-battling strategy, if farmers embrace it.
Previous studies conducted at Penn State and around the world showed the addition of 3-Nitrooxypropanol — often referred to as 3-NOP — to the feed of dairy cows reduced their enteric methane emissions by about a third. This follow-up research showed that the optimum dose of the white, granular compound made by Dutch health and nutrition giant DSM is 150 mg/kg —about a tablespoon in every 250 pounds of dry feed.
“The maximum mitigation effect was achieved with the three highest 3-NOP doses tested — with no statistical difference among 100, 150 and 200 mg/kg,” said researcher Alex Hristov, distinguished professor of dairy nutrition in Penn State’s College of Agricultural Sciences. “The decrease in methane emission yield in the study ranged from 16 to 36%, and emission intensity reduction ranged from 25 to 45%.”
3-NOP is the only substance that has worked significantly in reducing enteric methane in cattle and not had unacceptable effects on milk production or quality, added Hristov, who has experimented with many feed additives in recent years.