When formulating rations, Wisconsin's top dairy producers rely heavily on inoculated alfalfa haylage and processed corn silage supplemented with shelled corn and whole cottonseed as energy sources. Alfalfa is cut early and often, and all forages are chopped within recommended moisture ranges for optimal fermentation.

That's according to a survey that Randy Shaver and Bob Kaiser, University of Wisconsin-Madison dairy scientists, recently completed. They studied six selected dairy herds' production numbers as well as their management, feeding and harvest/storage practices.

“It's a snapshot picture that we do every few years,” explains Shaver. “We essentially try to capture as much information as we can and provide that to the industry. A lot of nutrition consultants and producers like to look at what some of these high herds are doing to compare it to what they're doing.”

During January and February of this year, the herds were examined using interviews with herd managers and their nutritionists as well as surveys, feed samplings and DHI milk testing program data.

“The six herds had a rolling herd average of 30,000 lbs of milk or above. In the past we've surveyed a wide range of herd sizes and housing types. But this time we focused on freestall-parlor herds ranging from 276 head to 566,” he adds.

All herds were fed TMRs. For high-production groups, on a dry matter basis, forage in the diet ranged from 45% to 53%; with corn silage accounting for 41% to 68% of it.

The farms cut alfalfa silage four times during the season.

“It's interesting to note that all of these herds used a lactobacillus inoculant on their alfalfa silage,” Shaver adds.

Storage-wise, three dairies stored alfalfa silage in bunkers, four used bags and two used upright silos. “There was a pretty heavy use of horizontal silos, even for haylage, but quite a heavy use of bags.”

Average dry matter in the 2003 alfalfa silage was 39%. On a dry-matter basis, crude protein averaged 21.4%, while NDF averaged 38.1%. NDF digestibility was 45%, on average. Mean particle length ranged from 0.22 to 0.53”. In a Penn State shaker box, 20% of the silage was coarse; 61%, medium; and 19%, fine.

For corn silage production, four dairies used dual-purpose hybrids, while one used brown-midrib hybrids and one used a combination of leafy and dual-purpose hybrids. Two bagged corn silage, four used bunkers and one also used piles. Four dairies used a lactobacillus inoculant, one used a liquid urea/molasses mix and one didn't use any inoculant.

“It's of interest to note that all six were using kernel processors on their choppers,” Shaver adds.

Corn silage dry matter content averaged 33% while, on a dry matter basis, crude protein averaged 8.7%; NDF, 43.8%; and non-fiber carbohydrates, 38.1%. NDF digestibility was 63%, on average. Mean particle length ranged from 0.34 to 0.51” and 18% of the silage was coarse; 68%, medium; 14%, fine.

“For corn grain harvest and storage,” he says, “four of the six were using high-moisture shelled corn and three of the six were using dry shelled corn — one herd was using both high-moisture and dry corn.”

Of the four farms storing high-moisture corn, at a dry matter content of 74-76%, two used uprights; the other two used bags.

Three of the four high-moisture corn dairymen added inoculants and processed the crop with roller mills. One also used a hammer mill for part of the crop and one processed with just a hammer mill. The two dry-shelled-corn farms processed with hammer mills.

For more survey information, visit www.wisc.edu/dysci.