Give your alfalfa or alfalfa-grass haylage a checkup, too, when you start feeding it, say nutritionists Brian Vaassen and Mike Hutjens. Their nutrition benchmarks:
- 1. Chemical analysis: Alfalfa haylage should be more than 20% crude protein, under 40% NDF, more than 50% NDFd and under 30% ADF. Alfalfa-grass haylage should be more than 20% crude protein, under 45% NDF, more than 50% NDFd and under 35% ADF.
- 2. Relative forage quality (RFQ): Hutjens likes to see a score around 130 for dry cows and heifers. For lactating cows, he recommends an RFQ score greater than 150, but Vaassen wants to see it in the 160-175 range.
- 3. Particle length: A shaken Penn State Forage Particle Separator sample should show 30-40% in the top box, 30-50% in the middle box and less than 40% in the bottom, Hutjens says. Vaassen prefers 20-25% on the top screen and 35-55% in the middle. If four boxes are used, Hutjens says the amount in the top two boxes should remain the same, with less than 30% in the third box and less than 10% in the bottom.
- 4. Fermentation: The pH should be less than 4.5. Ammonia nitrogen should be less than 10% of total nitrogen; lactic acid, greater than 4%; acetic acid, less than 2%; and butyric acid, less than 0.25%. Lactic acid should account for greater than 70% of total VFA.
See “Corn Silage Checkup.”