Improving Livestock Diet and
According to the old song, mares eat oats,
and does eat oats, and little lambs eat ivy. But what do cows and goats eat?
Would they rather eat something else? And how would it affect their health and
The availability of forage throughout the
year, from crops grazed on rangelands and pastures or harvested as hay and
silage, ensures livestock nutritional requirements are met. A well-fed,
well-nourished animal is a healthy and productive animal.
The U.S. livestock industry contributes
more than $60 billion in farm sales every year to the economy. Forage-based
livestock production ensures that forage is available and of ample quality to
meet the nutritional requirements of farm animals. Producers need dependable
resources and management practices that benefit livestock health.
An ARS national program, Rangeland,
Pastures and Forages, is concerned with the sustained and productive use of our
nation's natural resources. The program focuses on plant resources, forage
management, grazing management and how it affects livestock production and the
environment, as well as management of weeds and other pests. Resulting
technologies and management strategies help maintain our rangelands and
A related national program, Food Animal
Production, wants to improve growth and reproduction in livestock and poultry,
while also maximizing production efficiency. Part of its mission is to examine
how animals absorb and use nutrients. In order to improve animal nutrition, the
program directs research in the chemical composition and availability of
nutrients in feedstuffs. Researchers are exploring ways to achieve more
efficient use of nutrients while also minimizing non-productive nutrient
losses. They are determining the nutritional requirements of grazing and
non-grazing animals, with special attention on functions such as reproduction,
growth and lactation.
Across the country, ARS laboratories under
the direction of these national programs are finding solutions to problems
affecting the health and performance of livestock.
For example, researchers at the U.S. Dairy
Forage Research Center in Madison, Wis.,
improve digestibility and nutrition in forage crops such as alfalfa and
corn silage by modifying their cell walls so animals can extract more nutrients
from the crops. Studies there found red clover might be better silage in than
alfalfa in the Midwest. Cows eat less red clover silage but produce the same
amount of milk, and less nitrogen is excreted as waste.
Researchers in Madison
are developing an
expert system using equations that describe how variables affect the
nutritional value of forage, including the crop's growing environment, maturity
at harvest time, how it's preserved and how it's processed. The Feed
Information Technology (FIT) expert system combines data about the chemical
composition of forage with information from the user to help better understand
just how nutritious the forage is.
ARS researchers also are addressing
specific animal health problems that producers often encounter.
Researchers at the Fort Keogh Livestock
and Range Research Laboratory in Miles City, Mont., have found that if heifers
are fed to maximize
their growth from weaning to breeding, their skeletons and pelvises will be
large enough to deliver their first calves more easily. Earlier, the Miles City
researchers found that proper dietary levels of
fat may help calves withstand cold temperatures.
Henry F. Mayland of the Northwest
Irrigation and Soils Research Laboratory in Kimberly, Idaho, and colleagues
bred a hardy, new tall fescue grass, "HiMag," to
protect cattle, sheep and goats from an affliction known as grass tetany.
HiMag is unusually high in magnesium, so it should protect against a deficiency
of this mineral in grazing animals' blood. Taste tests showed that the animals
found the grass to be very palatable.
Mayland and other researchers also
analyzed tall fescue grasses to see what chemical and physical properties
grazing animals preferred. In another study, Mayland and colleagues found that
cattle, sheep and goats favored hays harvested in the afternoon. Shifting the
mowing of alfalfa hay from morning to late afternoon increased the animals'
preference for the plant. The same results held up in grazing studies.
Increased sugars in
afternoon forage could explain the increased number of bites counted in
afternoon grazing versus morning grazing.
These are just a few of the projects in
these national programs addressing livestock diets and nutrition. For more
information, visit the Web sites describing the
Pastures and Forages or
Animal Production national programs.
Or contact the following researchers:
Neal P. Martin,
Miles City, Mont.
Henry F. Mayland,
Agriculture officials from the
United States and Mexico recently commemorated
anniversary of a joint commission to eradicate the screwworm.
Although it's been almost 60
years since the United States rid itself of a tick that transmits bovine
babesiosis, the tick can still be found on cattle in Mexico. ARS researchers
have identified ways
ticks can become resistant to pesticides used in Mexico, and they found a
way to spot resistance more quickly.
ARS scientists and their
cooperators found improved performance, heat
tolerance and reduced mortality in chicks kept in higher than normal
temperatures for the first thee days after hatching.
ARS researchers are using Global
Positioning Systems (GPS)
technology to track
cattle. Managers want to disperse cattle more effectively on their pastures
and this technology can one day help them better predict where cattle will roam
The Fort Keogh Livestock and
Range Research Laboratory recently
broke ground on an
expansion of its main complex. The ARS facility in Miles City, Mont.,
focuses on beef cattle genetics and reproductive physiology, range animal
nutrition and range ecology and management.
ARS researchers recently found
that the legume pigeonpea could help fill
a gap in the year round availability of nutritious forages for livestock
Strinivas C. Rao
A protein could be used to
treat or prevent
bacterial infections that cause mastitis in dairy cows. ARS researchers
cloned the gene that produces the protein and recently filed for a patent on
An automated feeding system
developed in Europe eliminates the need for
crating sows during pregnancy. An ARS-funded project is testing the system
in the United States.
ARS researchers are joining
cooperators in testing
roundworms to fight pesky flies. The research will aid cattle producers in
finding reliable alternatives to chemical insecticides, which must often be
reapplied as fly populations rebound or migrate from other sites.
Malignant catarrhal fever (MCF)
is caused by a group of viruses and can be
harmful to bison and
cattle. ARS researchers and colleagues have developed tests to help
researchers and veterinarians detect and identify the disease transmitted by
The same amounts of bacteria and
other potentially harmful microbes are found on
chickens bred to be
featherless as are found on the skin surfaces of feathered chickens,
according to ARS researchers.
A newly released catfish line
consumes 10 percent
more feed and grows 10 percent faster than channel catfish now in
David L. Suarez,
Poultry Research Laboratory, received a
Career Award for Scientists and Engineers (PECASE) for research on how
chickens and turkeys contract avian influenza and for his contribution to
several new types of vaccines.