Animal Nutrition Viewed as a Key Step Toward Environmental Sustainability
CANADA - The development of nutrition strategies for improving the quality of manure to better reflect the needs of crops is one of the ways scientists are helping farmers address environmental concerns related to intensive livestock production.Last month (June 25-27) experts from across North America and Europe gathered in Winnipeg for Manure Management 2007 to interact with producers, municipal, provincial and federal government representatives and industry to discuss issues related to manure and the environment.
“The difference between human nutrition and animal nutrition is disappearing,” observes Dr. Martin Verstegen, a professor in monogastric nutrition at the Agricultural University of Wageningen, The Netherlands. “The reason is that we are not allowed growth promoters in animals in Europe anymore. That means you have to be a high quality farmer.”
Phosphorus Emerges as Key Environmental Concern
One of the biggest concerns related to manure management is the content of nitrogen and phosphorus, especially phosphorus.
“In grain feeds anywhere from 60 to 70 percent of the phosphorus is in this form of phytate so it isn’t readily available to pigs or animals,” says Dr. Martin Nyachoti, an associate professor with the University of Manitoba's Department of Animal Science.
“There’s a number of strategies available. One of which is currently commercially available is the use of the enzyme phytase that has been widely used in Europe and it’s used in quite a few farms here in Canada. That’s the enzyme that breaks down the phytate phosphorus and makes it available.”
Use of Phytase Among the First Regulations Implemented in The Netherlands
During the 1980s a great deal of research in The Netherlands was associated with phosphorus and with phytase. Dr. Verstegen notes the use of phytase was one of the first regulations the government of The Netherlands imposed on farmers and, over the past 15 years, all pig and poultry diets in that country have included phytase and it has been very successful.
“It means then you can have much less phosphorus in the soil and you can better comply with the regulation that you have no more phosphorus on the land than is taken out by the plants. That’s the regulation, even if the land is phosphorus poor.”
Phase Feeding Offers Another Alternative
Dr. Andrew Sharpley, a professor with the Department of Crop, Soil and Environmental Science at the University of Arkansas says that many dairy and hog farms in the U.S. now use a phase feeding system – matching the nutritional components of the diet to the specific stage of development of the animal being fed.
Dr. Sharpley estimates, “You can feed an animal different amounts of nutrients so you can cut back 30 or 40 percent on the nutrients that are brought onto the farm just in feed.”
New Grain Varieties Offer Additional Promise
Dr. Nyachoti adds, “Another strategy is to use feed ingredients with high levels of digestible phosphorus, ingredients such as distillers’ grains. There have become available ingredients that have high available phosphorus that have been developed.”
He suggests, “If we can get those available in Canada obviously that will become a huge benefit. They have been developed at the Crop Development Centre in Saskatoon. However there are some regulatory issues that need to be resolved before we can actually utilize them as a feed ingredient and we would like to see that resolved. When they become available as commercial ingredients they will go a long way in enhancing phosphorus utilization.”
Phosphorus Reductions Possible Without Reducing Productivity
Dr. Verstegen points out producers in The Netherlands have reduced the amount of supplemental phosphorus given to pigs from 1.6 kilograms per pig to 0.6 kilograms per pig, a 150 percent reduction compared to 25 years ago.
“That’s gigantic,” he says, “And still the production increases in Europe. Our cows give, every year, 15 hundred kilograms more milk than the year before. Our pigs, every year, have less feed per kilogram gained.”
Producers Encouraged to Balance Nutrients Coming In with Nutrients Going Out
Dr. Sharpley believes one of the keys is to balance the level of nutrients we bring onto farms with what is going out. “Obviously as we get more specialized in our agriculture production systems, just to be economically viable and competitive, we tend to get more concentrated and more nutrients come in than go out.”
He explains, “The nutrients come in feed and fertilizer. I think we’ve helped farmers do a pretty good job of fertilizing pastures or cropland to meet crop needs. The imbalance starts to occur when you have a large number of animals in a smaller area because that's the most profitable way to operate. You tend to get more nutrients coming in in feed. That’s to a certain extent local crops but there’s some mineral supplements that the animals need. That’s what we see as being one of the main areas where more nutrients are coming.”
He says, “Going back out it’s mainly in the produce, in the protein or in grain or forage if it’s hay and it’s being cut and it’s being taken off farm and sold so nutrients are being removed that way.”
Land Base a Limiting Factor
Dr. Sharpley suggests one of the biggest challenges relates to land base. “We’ve seen farms, especially here in the U.S. and I'm sure it’s similar everywhere, have tended to grow and get more concentrated, increased numbers of animals on smaller acres.”
“With the pressures on agriculture and urban development we often see there isn’t the land, or that land is too expensive, so it gets more concentrated which aggravates this accumulation of nutrients,” he says.
However, he observes, “One of the things we’re seeing is that the value of these nutrients now in some of these systems is much greater because of the cost of energy. We’re looking at making energy out of manure, we’re looking at different products that may be a revenue stream for farmers that were never there before. Those are some of the opportunities. We’re not there yet but I think we are learning a lot and perhaps learning to adapt fairly quickly.”
Nutrition Expected to Play a Bigger Role in Environmental Protection
Dr. Verstegen believes, “In future animal nutritionists will be part of an integrated mineral and manure management. At the moment the big gains can be obtained there.”
He suggests, “Quality of production is not only efficient production. The quality of production is also that the animal, in the eye of the non farm community, has had a decent animal life.”
He points out, “The animal develops a lot of changed behaviors and if you change nutrition you can change that and still have the same growth, the same efficiency.”
Dr. Sharpley suggests there is a need for more public education. “They are trying to do it through schools [but] it will take time. We hear about examples of kids going to these environment days or what ever and then they go home and tell their parents well you should be doing this, you shouldn’t be doing that. They kind of educate their moms and dads so that’s a plus.”
Manitoba Viewed as Ahead of the Curve
Dr. Sharpley observes, “From what I’ve seen in the field tours and the trips and the people you have working here it seems like you’re [Manitoba] probably well ahead of the game in addressing these issues. You’ve got the communications, you’ve got the demonstrations and so, from what I see, Manitoba is a lot more further ahead than many places in the U.S. in terms of dealing with the issues.”
He acknowledges, “Obviously you have an issue that most areas do, that most of the people in the watershed don’t live on farms or near farms and so they don’t quite understand all the time what farming is all about and what it does for them and so that’s always an issue.”
Environmental Concerns Top of Mind Among Farmers
“Irrespective of the cost,” says Dr. Sharpley, “I think most of the farmers, 99.9 percent of them, are good stewards. Obviously, they’re there to make a living and it's a way of life but, everyone that we speak to, if they feel like they’re causing a problem, they would want to do something about it. Now the rubber hits the road if it’s so expensive it’s going to stop them from doing what they’re doing or put them out of business. That’s a different situation. But, philosophically, if they knew they were causing a problem, they would do what was within their means so to speak to correct that.”
He suggests, “Some of it is economic and some of it is just darn good stewardship or a desire to not be part of a problem.”