Benefits the whole farm!
AMES. Iowa—At first glance, swine
production doesn't seem to play a major role in sustainable farming
systems. If anything, hog production may contribute to ecologically
unsound agriculture, both by encouraging row-crop production
on marginal land and by producing manure which can pollute surface
water and groundwater.
But it doesn't have to be that way. Hogs can be raised using practices that are profitable as well as humane and ecologically sound. These practices also can create much-needed jobs in the Corn Belt, and improve both the quality of pork produced and the quality of life for pork producers. The key is rethinking management to meet the needs of the whole hog, to the benefit of the whole farm.
Mixed crop-livestock farms make sustainable farming easier by providing diverse crops, manure to cycle nutrients, value-added livestock to sell and year-round employment for farmers. In the Corn Belt, hogs are the livestock of choice. In Iowa, they account for one-third of our state's cash farm income. Forty percent of Iowa farms have hogs, and the pork industry employs about 4.3 percent of our workforce.
In recent years, hog production has been concentrated on fewer and larger farms. The average number of hogs per farm in Iowa has risen steadily from fewer than 100 in the '50s to more than 350 in 1987. Farms producing more than 1 ,000 head per year accounted for nearly half of all hogs marketed in the state. Nationwide, such farms account for 70 percent of hogs sold.
Even with increasing concentration smaller producers can remain competitive by taking advantage of Sus scrota's remarkable versatility and ability to fit into sustainable farming systems. Here are five areas to watch.
Pig rations in the Corn Belt consist primarily of corn and soybeans. But they don't have to. Nutritionists know that pigs can use a wide variety of feeds. In fact, F.H. King noted this important role for pigs nearly 80 years ago in his description of Chinese agriculture, Farmers of 40 Centuries: "It is remarkable," he wrote, "that these ancient people came long ago to discard cattle as milk and meat producers; to use sheep more for pelts and wool than for food; while swine are the one kind of the three classes which they retained in the role of middleman as transformers of coarse substances into food."
The Corn Belt pig also is such a middleman, now for quality grains. By changing the Corn Belt pig's diet, we can change the face of Corn Belt agriculture.
Hog production built around a more diverse crop base would be more sustainable because it would fit in better with life in the Midwest, from soil microbes to human activity. Just producing corn and soybeans for export is not sustainable over the long haul. The pig, one of the major reasons for intensive production of these two crops in Iowa, is an extremely versatile animal. The limitation comes from the mindset of the producers, our economic system, policy (to some degree) and the past. While government policy now supports the value of corn, future calculations may factor in benefits of alfalfa because of its environmental contributions.
The digestive system of the pig is similar to humans, which some people say makes it a competitor with humans for food. The other way to look at it is that it can be used to eat the things we don't, like animal and food processing by-products and kitchen wastes available in quantity near Midwestern population centers. These sources are associated with problems such as pathogens, quality variability and bulkiness, but there is potential, as well.
Because gestating sows have low energy needs and large digestive tracts, fibrous feedstuffs and protein by-products can make up as much as 90 percent of their rations, studies show. High levels of alfalfa hay or haylage can maintain or even improve reproductive performance. Also acceptable are alfalfa-orchardgrass hay, grass silage, sunflower and soybean hulls, distiller's grain, corn-gluten feed, corn and cob meal, beet pulp, and wheat middlings. Even growing-finishing rations can be 10 percent to 30 percent forage, if energy levels are maintained.
What's exciting about all this is how increasing forage levels in swine feed would change cropping patterns in the fields. Take a hypothetical 400-acre corn-soybean operation producing 2,000 hogs annually with no forages. It would require 70 acres of alfalfa for the legume to make up 25 percent of the ration, at 210 pounds per head per year. This would put 17 percent to 20 percent of the farm in alfalfa every year. Think of the tremendous effect this would have on fertilizer needs, weed control, water quality and soil conservation.
If you encourage farmers to add forages to their corn-bean rotation, they ask, "What will I do with the hay?" "Feed it to the pigs!" is one answer. If all pork producers in Iowa fed 25-per-cent alfalfa, it would increase acreage 15 percent to 350,000 acres.
As more hogs come from fewer farms, swine housing is almost synonymous with confinement. Many confinement facilities were built in the '70s when labor costs grew faster than capital costs and inflated asset values were leveraged to pay for new construction. As a result, from 1973 to 1982, fixed costs of depreciation, taxes and insurance nearly doubled from $1.94 to $3.80 per hundredweight, according to Iowa State University studies. However, the studies show, the increase in efficiency with these structures generally isn't enough to offset increased costs. Partially to blame were overly optimistic estimates of useful life for confinement facilities. Five to seven years is often the range, rather than 15 to 20 years as predicted in the '70s.
The move to confinement was fueled by the capital-for-labor tradeoff. Also, producers traded weather and predator risks for increased financial risk. With the flip-flop of the '80s — soaring capital costs and falling labor costs — many of these investments in closed buildings turned sour.
The buildings also brought air-quality problems, which you know about if you've spent much time in a confinement structure. Ammonia, hydrogen sulfide, carbon monoxide and carbon dioxide gases often are present at dangerously high levels, especially in farrowing and nursery units, where producers spend most of their time — and small pigs are most susceptible to airborne health hazards.
Fortunately, there are healthy alternatives to confinement that are just as profitable — if not more so. Studies have shown no major differences in gain and feed efficiency between environmentally regulated and open-front housing in the Corn Belt. Pasture farrowing is another example. Traditionally, this system has been viewed as high-labor, low-cost and low-management. When coupled with intensive management, it can be very profitable.
The bottom line is that pig production can net more dollars and be more sustainable using systems that are not dependent on confinement. Pasture-based operations are particularly well-suited for hilly areas where ridge-tops and bottomlands can be intensively cropped and marginal hillsides can support a corn-oats-alfalfa-hog pasture rotation.
Hogs in Iowa produce about 33 billion to 39 billion pounds of manure each year. Spread evenly over the state's 10 million acres of corn, it would equal application of 100 pounds of 25-8-16 per acre, worth nearly $10 per acre. Assuming no losses, that manure could supply one-quarter of the state's corn with 100 pounds of N per acre.
The downside is that if manure is not stored, handled and applied properly, its nutrients can be lost and, in turn, pollute the air, surface water and groundwater. Confinement systems do make manure easier to recover and control.
Managing manure well is a challenge, especially with its variable dry matter and nutrient content. Application equipment limitations are one bottleneck. In our Ag Systems Project in Newell, Iowa, we were unable to adjust our spreader to apply fewer than 10 tons per acre. The resulting applications supplied 200 pounds of N, much more than was needed.
In the eastern part of the state, ISU Extension has set up a promising solution: a manure brokerage system which allows livestock producers with too much manure to apply their excess to fields on cash-grain farms where it's needed.
4. Health And Genetics
The genetic base of U.S. swine is fairly narrow. Eight breeds make up the majority of the population, with three or four breeds predominating. Three Chinese breeds recently imported by researchers at ISU, USDA and the University of Illinois show promise of broadening genetic diversity to increase pig performance.
In confinement, genetic disease-resistance is critical. One-third of all pigs had been affected by health problems in a survey by the University of Missouri in 1978 and 1979. Scours, pneumonia, salmonellosis, transmissible gastro-enteritis and influenza are all familiar problems to most confinement hog producers. Interestingly, pasture swine producers had the lowest health costs in the study.
Two controversial routes to swine profitabilty are subtherapeutic antibiotic use and porcine somatotropin (PST)- swine growth hormone, which is likely to be approved for use in the near future.
While there is no definitive conclusion on the human health effects of routine low-dose antibiotic use in livestock, some in the scientific community feel it's risky. Consumers will undoubtedly question the safety of PST pork, just like they are currently resisting BST-produced milk.
Instead of focusing on these additional inputs, perhaps more is to be gained from an emphasis on management practices that prevent disease and maintain herd health —especially with consumer concerns about food safety.
Already, many producers are actively working with veterinarians to develop comprehensive health-care plans to reduce the need for more expensive cures.
5. Animal Behavior And Management
Animal welfare is another hot topic in livestock production. In Europe, gestation crates and sow tethering have been outlawed. We haven't felt these effects here in the Corn Belt, but it looks like only a matter of time before we do.
Certainly swine production could benefit from studying how to use pigs'natural behavior to an advantage. An Ilinois study looked at how pigs eat from a variety of commercial feeders. Based on the results, researchers designed an improved feeder that better fits hogs and reduces waste. A recent study at the University of Illinois showed cloth strips and industrial hoses, suspended over pens, as toys, lessen negative behaviors. Under way are follow-up studies on whether toys effect feed conversion efficiency.
The shape of the perfect pig farm has yet to be found. In developing more sustainable swine production systems, economic, environmental and animal welfare concerns don't always seem to work together. Compromise sometimes is necessary in designing whole-farm systems with swine. The end result will be more sustainable, however, when pigs' behavior, biology and ecology are central to the plan and are not overridden by equipment, drugs or other constraints.
Mark Honeyman has a doctorate in animal nutrition with a swine emphasis. He spent four years farming using pasture farrowing He is coordinator of the Iowa Agricultural Experiment Station's Outlying Research Centers, and coordinator of animal sciences at Iowa State University. This article is adapted from a paper he presented at the Leopold Center for Sustainable Agriculture conference, "New Developments in Cropping Systems and livestock Management Systems," Feb. 7, 1990.