Ammonia Emissions from Dairy Farms - The Basics

Dr. Maurice Eastridge, Extension Dairy Specialist, The Ohio State University

Similar to other sectors of agricultural production, the dairy industry is undergoing constant change. There is less than 2% of the human population today involved in agricultural production, yet the growth in population is demanding an increasing supply of food. Therefore, food production enterprises have increased their number of productive units (acres or animals) and made advances in improving productive efficiency per unit.

Ohio's dairy industry has been following the national trends: decrease in number of farms, increase in number of cows per farm, and an increase milk yield per cow. The number of dairy farms has decreased by about 70% since 1970, but during this time period, the number of cows per farm has more than doubled from about 25 cows/farm to 58 cows/farm. This change in herd size in conjunction with the increase in milk yield per cow (about 2% per year), has resulted in a somewhat stable milk supply for the State, allowing the State to maintain its rank of 11th in the nation for total milk production. With this milk supply, plus milk from other states, the milk processing industry in Ohio has remained strong despite the decrease in total number of manufacturing plants (Ohio's ranks 5th for number of manufacturing plants). This processing capacity has helped the State to maintain a strong dairy industry and for the State to maintain its rank of being 1st in Swiss cheese production.

The dairy industry in Ohio is a major contributor to Ohio's economy. The value alone of the milk produced in 2003 was $588 billion, and for each dollar generated on a dairy farm, in excess of $2 is generated elsewhere in the economy. For every employee on a dairy farm, about 2.25 jobs are generated elsewhere in the State for processing dairy products and providing goods and services to the dairy industry. The economic development impacts of the dairy industry are significant.

There have been increased environmental and social concerns with the increasing size of dairy operations. This has occurred with the increased number of nonfarm people moving to live in rural residences and with more animals per unit of land base in given areas. Actually for Ohio, the number of agricultural acres per animal unit (based somewhat on animal size) has increased from about 5.7 to 7.6 acres (data exclude horses and poultry). The increase in number of animals within a given community and the extensive use of liquid manure systems have contributed to these concerns. Even though some large dairy farms are on a relatively small amount of acreage, the farmers contract with local crop farmers for feed production and for land application of manure to provide nutrients for the cropping system. Nutrient balance and manure storage and handling systems will continue to be major points of focus for dairy farms. Environmental stewardship and social responsibility are of focus by today's dairy farmers. However, new regulations for reducing the risks for water and air contamination are going to have cost implications to the dairy farmer without notable increases in the price they receive for their food product.

Within Ohio, the regional distribution of the dairy industry has begun to shift. Traditionally, the northeast and west central areas have been the most concentrated areas for dairy farms. In northeast Ohio, the number of herds is decreasing midst an increase in tourism and the increase in lot size for residences within a densely populated area of the State. The northwest area of Ohio in increasing in number of herds and they are of large size. This has been an attractive area because of the land base for feed production and the lower population density. With the new herds moving into Ohio and expansion of herds already in Ohio, the number of cows in the State increased between 2003 and 2004. There have been dramatic decreases in number of farms with less than 29 cows and 50 to 99 cows, but the number of farms with 29 to 50 cows has remained somewhat stable because of small increases in herd size by farms that sale manufacturing grade milk and with the possibly of only one family member needing to work off of the farm. The number of farms with 100 to 199 cows has also remained somewhat stable, but farms with 200 cows or more have been increasing in number; at the end of 2004, Ohio had 35 herds with 500 or more cows.

Ohio has the feed resources and dairy industry infrastructure to sustain a vibrant industry. The increase in number of large farms and increase in herd size of most farms will result in stable to upswings in number of cows and total amount of milk produced in the State. Although there has been consolidation in the processing industry and loss of some small processors, Ohio will continue to have more capacity to process milk than supplied from within the State. Increasing input costs, including changes in feed costs based on weather and other market forces, and volatility of milk prices require that dairy producers operate their enterprise in an economic manner. In addition, responsibilities for sustaining the environment and being attentive to social issues will have cost implications. Yet, the pride in providing a high-quality food source midst a desirable way-of life and the desire to work with animals will continue to be motivating forces for Ohioans to remain in the business of producing food.