Bags May Beat Towers for Forage Storage
Farmers can save on initial costs plus up to $10,000 a year,
while greatly reducing the risks from falls and silage gas. As
anyone who has driven across rural Wisconsin can tell you, tower
silos are one of the most prominent features on the landscape.
Up to 100 feet high, these domed towers are the traditional method
of storing forage to feed livestock during the winter. In recent
years, however, huge plastic "sausages" have sprouted
throughout farm country. The sausages are bag silos or silage
bags, a new way to store feed for livestock. In terms of cost,
safety and feed quality, silage bags—long, plastic tubes
tightly packed with chopped forage—may be a better choice
for farmers, according to one University of Wisconsin-Madison
"For both initial investment and annual costs, silage bags
save farmers money—up to $150,000 initially and $10,000
per year for a 220-cow herd—over using tower silos or bunkers,"
says Gunnar Josefsson, a farmer health and safety expert with
the College of Agricultural and Life Sciences. "Farmers can
talk to their county extension agent to find out what the savings
would be for their farm. And, in addition to saving money, silage
bags greatly reduce the danger of falls and exposure to silage
Safety is an important issue when it comes to storing silage.
In Wisconsin, an average of three people die each year in accidents
from silage handling—about 10 percent of total farm fatalities—and
more are injured. The chief causes of injury or death are related
to tower silos: falling from high elevations and exposure to gas
from fermenting forage. Bags, at about six to nine feet tall,
pose little risk of falls. And, although silage in bags still
produces toxic gas, the farmer does not need to enter a confined
Most Wisconsin farms use tower silos, but bags are becoming increasingly
popular: Josefsson estimates that almost half of farmers use bags,
even if not on a regular basis. "When farmers expand their
operations, bags are often the best choice because the silage
bag system can be tailored to any size herd. With bunkers and
towers, if you don’t have enough cows to consume the feed
at a certain rate, there can be spoilage from contact with the
However, a temporary solution often becomes a permanent fixture:
bottom-line cost analysis makes it clear that bags are advantageous
at any scale of operation. "Farmers have to purchase bags
each year, and some of the costs of silos, such as the initial
investment, are hidden because they are included in a mortgage."
Josefsson explains. "However, bags are not included in property
taxes as silos are, and you can always sell your equipment for
bagging—but you can’t sell a bunker or tower, and
it adds very little to a property’s sale value."
Bagging also offers options for farmers other than purchasing
the equipment outright. Some farmers share the equipment with
one or more neighbors, while others rent the equipment from a
dealer or hire an operator to bag their forage. However, Josefsson
says that it is hard to generalize what option is most cost-effective,
as it depends on the farmer’s specific circumstances. Another
benefit of bagging is that, if the silage is managed well, using
bags can improve feed quality and reduce spoilage, Josefsson adds.
With towers or bunkers, farmers must use the feed in a certain
order. However farmers can access feed in bags from either end,
and can mark which sections contain high-quality feed so that
it can be given to top-producing cows.
According to Josefsson, one of the problems with using bags is
disposing of the plastic afterwards. Some landfills may not accept
bulk plastic, or accept it only with an extra charge. One common
practice is to burn the used plastic, but burning is illegal and
bad for the environment. "Farmers are really looking for
an improved way to properly and legally dispose of waste plastic,"
Josefsson says. Already, one manufacturer plans to begin accepting
and recycling used bags later this year, and Josefsson predicts
that the industry, under pressure from farmers, will begin absorbing
the cost. Another potential solution is for farmers to bale their
plastic and store it until it can be transported to a landfill
or recycling plant.
Genome Sequencing Completed for Major Dairy Cattle Microbe
USDA and University of Minnesota scientists have sequenced the
genome of the bacterium that causes Johne's disease, a devastating
ailment of dairy cattle and other ruminants. A chronic and potentially
fatal intestinal disorder that brings about severe diarrhea and
weight loss in infected cattle, Johne's Disease is found in 8
percent of beef herds and 22 percent of dairy herds in the U.S.
"This major research breakthrough could speed the development
of new ways to detect and ultimately eliminate Johne's disease,"
said Under Secretary for Research, Education, and Economics JOSEPH
JEN, who chairs the U.S. Interagency Working Group on Domestic
Animal Genomics. The genome sequencing was achieved at two locations:
the Agricultural Research Service (ARS) National Animal Disease
Center in Ames, IA.
New Trap Kills House Flies
A new trap invented by Agricultural Research Service scientists
attracts kills and retains the bodies of houseflies, offering
a promising alternative for fly control in areas where food products
are stored or prepared. Indoor flies are a potential health hazard
to humans because they can transfer numerous disease organisms
by just walking across exposed foods. Using chemical pesticides
against them is risky if the chemicals are applied near food.
And most flytraps have been designed for use either outdoors,
or indoors in agricultural settings.
Now scientists Jerome A. Hogsette and David A. Carlson at the
ARS Center for Medical, Agricultural and Veterinary Entomology
in Gainesville, Fla., have designed a new trap that overcomes
those problems. Dubbed "Flybrella" by Carlson, the trap
resembles an upside-down umbrella. It can also be used to capture
other flying insects, according to Hogsette, a research entomologist
with the center's Mosquito and Fly Research Unit.
Flybrella lures flies by taking advantage of their natural attraction
to selected chemical odors and to vertically hanging objects.
After entering the trap, flies eat the poisonous bait. Dying flies
fall inside a tube and into an inverted plastic cone attached
beneath. The trap has a removable cylindrical body, a toxicant
panel and an insect collector. It is designed to contain the dead
flies and conceal them from sight. Flybrella hangs from a hook
or is attached by ties to electrical cables or other vertical
surfaces approximately six feet from the floor.
Two Flybrellas captured 98 percent of flies released in laboratory
studies. The trap would be ideal for supermarkets, restaurants
and any store where food is prepared or kept. Flybrella is safe
and inexpensive to produce. It uses the QuickStrike toxicant strip
Hogsette helped develop for agricultural use in the early 1990s.
QuickStrike has been very successful at controlling flies in poultry
facilities. One of its ingredients is Muscalure, a sex attractant
discovered by Carlson and widely used in commercial fly baits.
Latest New-Age Health Supplements: Garlic, Kale And Beets?
With so many people using over- the-counter herbal supplements
as a means to promote health, one UW-Madison researcher is wondering
why we don't hunt for health-promoting properties among the ordinary
plants we grow for food. According to Kirk Parkin, a food scientist
at the College of Agricultural and Life Sciences, "There's
no reason to believe that exotic botanicals are the only plants
that have specific, health-promoting benefits.
Domesticated plants do, as well." That's why Parkin has
launched a research program aimed at uncovering the healthful
properties, such as cancer prevention, of the decidedly unglamorous
crop plants cultivated here in Wisconsin, such as garlic, kale,
beets, corn and green beans. Not only do common vegetables carry
a lower price tag and a safety record spanning thousands of years,
but they also contribute to Wisconsin's economy.
The popularity of exotic herbal supplements with names like echinacea,
feverfew, valerian and goldenseal has soared. So have concerns
about their effectiveness and safety. Last year, the Food and
Drug Administration alerted consumers to the possible liver-damaging
effects of kava, a popular herb for relieving anxiety and insomnia.
The Secretary of Health and Human Services recently urged mandatory
warning labels for the stimulant ephedra. And doctors have begun
cautioning about the risks of using herbal supplements in combination
with prescription drugs and immediately before surgery.
On the other hand, in a study published in the September 2002
issue of the Journal of Food Science, Parkin's research group
demonstrated that everyday vegetables might indeed play a role
in human health beyond simple nutrition. Using a well-known in
vitro technique for screening possible cancer-preventive agents,
they showed that crude vegetable extracts triggered increases
in protective proteins, called phase II enzymes. Phase II enzymes
work in concert with another group of proteins, called phase I
enzymes, to detoxify cancer-causing agents in the liver and other
organs, and purge them from the body. Due to these activities,
high levels of both sets of proteins — but especially phase
II enzymes — are thought to help protect against cancer.
Among the vegetable extracts they tested, an extract of sweet
corn showed the greatest effect, causing a 13-fold jump in enzyme
levels. Kale extract raised the enzymes eight-fold, snap beans
increased them five-fold and beets two-fold. "Our results
suggest that commonly consumed vegetables contain components that
can elevate phase II enzymes in vitro, and have the potential
to be used as dietary sources of cancer chemopreventive agents,"
says Parkin. Many of the extracts also showed pronounced antioxidant
But aren't people already receiving these benefits by eating
their veggies? Probably not to the extent they could. In its last
dietary assessment of the U.S. food supply, the U.S. Department
of Agriculture found that although Americans ate an average of
20 percent more vegetables in 1996 than in 1970, just three types
accounted for half of all servings: head lettuce, canned tomatoes,
and potatoes, including chips and french fries. Another 15 percent
of servings came from dehydrated potatoes, fresh tomatoes, garlic
To entice people into eating a wider variety of plant foods,
Parkin believes scientists need to continue to pinpoint the health
benefits of eating specific vegetables. "The USDA has been
advocating all along that eating a diversity of fruits and vegetables
in copious quantities will promote health, and I'm convinced it
will," he says. "But I think if you simply tell the
public that eating vegetables is good for them, you don't get
much of a response. To change eating habits, you need to give
a specific reason why eating certain vegetables will benefit them."
Research such as Parkin's could also lead to new vegetable-based
dietary supplements for the staunchly veggie-phobic. Parkin cautions
that his research group still has much work to do toward characterizing
the specific compounds in vegetables that carry cancer-protective
effects, and demonstrating a true health benefit for people. Still,
he's convinced that today's neglected, humdrum plant foods could
be an important part of tomorrow's preventive medicine.