Results of a nationwide survey to determine feedstuffs fed to lactating dairy cows.

A nationwide survey to determine feedstuffs used in the diets of dairy cows was conducted. This survey was mailed to dairy nutritionists at universities in each state to describe the use of 144 feedstuffs. Twenty-eight states responded and were grouped by region as follows: Northeast (Maine, Maryland, New Hampshire, New York, Ohio, Vermont, and West Virginia), Northwest (Idaho, Oregon, and Washington), Midwest (Iowa, Illinois, Michigan, Minnesota, Missouri, Nebraska, North Dakota, South Dakota, and Wisconsin), Southeast (Florida, Georgia, Kentucky, South Carolina, Tennessee, and Virginia), and Southwest (Arizona, Oklahoma, and Texas). Comparisons of the feedstuffs most commonly fed, the maximum inclusion rate of feedstuffs in the diet, and how these feedstuffs were fed (alone or in a mixed diet) were made. The maximum percentage fed was also reported. Overall, concentrate feeds were fed blended with other ingredients more often (98.7% of the time) than forages (67.8% of the time). Also, forage was fed at a higher percentage (42.3%) of the total diet relative to individual concentrate ingredients (16.3%). Corn silage, soybean meal, corn grain, alfalfa hay, and grass hay were common feeds across all regions. However, the use of by-product feeds was variable depending on local availability.