Many dairy herds have the potential to lower ration crude protein levels by at least 0.5 to 1.0 unit without impacting herd milk production, according to Larry E. Chase, Professor and Extension Specialist, Department of Animal Science, Cornell University. Significant economic and environmental impacts can accompany these changes.
Dairy producers are realizing two incentives for lowering ration crude protein levels. One is to improve profitability by more efficiently converting feed nitrogen intake to milk nitrogen output while maintaining or improving milk production. Income over feed cost (IOFC) increases along with income over purchased feed costs (IOPFC) as purchased feed costs decrease.
Secondly, feeding rations with lower crude protein decreases the excretion of nitrogen into the environment and lowers ammonia emissions. Consequently, the number of acres needed for land application of manure decreases. When ammonia emission regulations are implemented, the lower animal ammonia emissions will be beneficial.
A limited number of commercial dairy farms have already made the step to feeding lower crude protein rations, according to Dr. Chase. With these farms, limited opportunity may exist to further lower ration crude protein. These dairies, however, demonstrate that lower crude protein rations can be used in herds while maintaining high levels of milk production.
When determining if a herd is a candidate for lower ration crude protein levels, consider:
1. Is the current ration crude protein level greater than 16.5% crude protein?
2. Are herd milk urea nitrogen levels greater than 12 mg/dl
3. How consistent are the daily feeding and feeding management procedures?
4. How consistent are forages and are forage dry matter analysis done at least 2-3 times per week?
5. Do the nutritionist and dairy producer both believe this approach will work?
6. How will the potential responses to adjustments in ration crude protein levels be monitored?