By VICKY CARSON
We’ve all heard pseudo-scientists and friends of the environment claim that production agriculture contributes more to greenhouse gases and pollution than all of the cars in America.
No matter whether they’re right or wrong, we dairy farmers need to ask ourselves: Are there things that we can do to reduce waste and pollution?
It’s in our best interest to protect our environment and land so the next generation has the opportunity to farm.
What if I told you that you could be a better environmental steward — and reduce feed costs?
Key Points
• Manure volume and feed costs can be cut via simple diet changes.
• Ionophores and fermentation enhancers boost rumen efficiency.
• Consider replacing alfalfa silage with grass and corn silages.
We can do it
Recent research presented at the Penn State Dairy Nutrition Conference shows that we can reduce nitrogen, carbon dioxide and methane by changing cow diets. And feed costs can be reduced by addressing three areas.
• Methane and CO2: We can reduce methane and CO2 by improving diet digestibility. That makes sense. The more feed dry matter converted to organic matter (nutrients the cow can use for productive purposes), the less waste (manure and gas) is produced.
Improving forage quality via higher-digestibility varieties is one way to increase diet digestibility. We can do it without compromising yield.
I recommend, for example, planting 25% to 30% of corn in brown midrib, or BMR, hybrids, and the rest as high-yielding silage corn.
I also recommend mixing BMR corn silage with regular silage corn in the silo and feeding it throughout the year, taking advantage of higher-starch, higher-digestibility BMR corn silage with the neutral detergent fiber benefits of silage corn.
Yes, that may mean some creative planting. But it can be done.
If your herd is seasonal or you have the ability to feed early-lactation cows separately, then I’d try to separate some BMR corn silage to be fed to cows in early lactation.
• Ionophore methane-reducers: Ionophores, such as Rumensin, reduce ruminal methane by reducing the efficiency of gram-positive bacteria — the biggest methane producers — in the rumen. Rumen methane production “eats” about 12% of gross feed energy. Reducing methane makes more energy available for the animal.
Ionophores also increase ruminal propionate production. Propionate is the primary precursor molecule for glucose. More glucose means more lactose synthesis, which means more milk is synthesized per pound of feed. Increasing feed efficiency reduces manure and gaseous waste.
• Microbial boosters: Other fermentation enhancers, such as Fermenten (a mix of rumen-soluble nitrogen and soluble carbohydrates), also improve feed efficiency by feeding rumen microorganisms the nutrients needed to grow and reproduce efficiently.
More microbes mean more efficient ruminal conversion of feed dry matter to organic matter. They also mean more milk on lower-nutrient-density diets, and reduced environmental wastes and lower feed costs.
Formulating diets to reduce manure produced per cow is doable. And, it’ll reduce the amount of nitrogen and phosphorus going on our fields, as well as the potential for runoff.
The diet changes don’t compromising milk production, and are likely to reduce feed costs.
Reducing dietary crude protein reduces the manure and urine produced, but not milk or milk protein yields. Since protein is one of our highest-priced dietary ingredients, feeding less of it decreases feed costs.
Carson and husband Steve partner in Harkdale Farms of Newbury, Vt. She’s also a professor at Vermont Technical College.
Here’s how to make it work for you
By reducing ruminally degraded protein, or RDP, excesses in the diet, we reduce urine volume, milk urea nitrogen and ammonia. We also spare energy for the cow to use for other productive purposes.
An easy way to reduce dietary RDP is to reduce soybean meal, canola meal or urea added to the diet. Reducing feeds such as distillers grain, corn gluten feed and meal can also help.
But the greatest impact on manure and urine volume might be made by reducing the contribution of alfalfa forages. Yes, that’s almost heresy. Replace them with grass and corn silage.
Replacing alfalfa silage with corn silage has the greatest impact on manure volume. Alfalfa silage tends to increase dry matter intake; as intake increases, rate of passage through the rumen increases and diet digestibility decreases.
Feed passing through the rumen too quickly isn’t completely fermented. So a greater proportion ends up passing through as manure. Increasing corn silage in the diet increases diet digestibility and reduces manure volume.
Challenge your nutritionist to help you. Simple diet changes can reduce manure and urine volume — and your operation’s environmental impact!
Fewer refusals saves money
Minimizing feed refusals is one way to cut feed costs — assuming you’re putting high-quality feed in front of your cows. Checking forage dry matter regularly is the simplest, cheapest way to reduce feed refusals.
Adjust your chore routine to favor times when cows are more awake. Make sure that fresh feed is available.
Or push up feed during those times of day to increase feed intake and reduce refusals. All extra effort is likely to improve milk yield without costing a lot of extra money.
This article published in the February, 2010 edition of AMERICAN AGRICULTURIST.
All rights reserved. Copyright Farm Progress Cos. 2010.