Agriculture Reference
In-Depth Information
Deworming
There are many drugs available to help control worms. (For more about spe-
cifi c deworming drugs, see Drugs for Sheep, starting on page 226.) Until
recently, the common approach for shepherds was to set up a worming sched-
ule and follow it religiously by worming every 3, 4, 6, or 8 weeks. The problem
with this method is that it is costly and has led to drug resistance in the para-
site population.
Today more shepherds and the veterinarians who work with them are
coming to terms with fl exible worming programs that are tailored to the
needs of the individual farms. For example, on farms where worms are only
an occasional hazard — such as when pastures are understocked, sheep and
cattle are grazed alternately, and pastures are rotated — treatments may only
be needed when parasitism becomes evident through fecal tests. For areas in
which worms are especially bad, such as the Southeast, regular use of herbal
products and regular testing of fecal samples provide a good strategy. If the
fecal samples have particularly high worm counts, then supplemental use of
a pharmaceutical dewormer (or anthelmintic) is in order.
Keep in mind that frequent worming increases selection pressure on the
worm population, and resistance may become a problem sooner for you than
for a neighbor who worms less often. “How often do I need to worm?” has the
FAMACHA
FAMACHA is a new system for evaluating worm infestations by com-
paring the color of a sheep's lower eyelid to a scoring chart. The
system essentially evaluates anemia. Developed in South Africa,
the system has recently found its way to the United States via the
University of Georgia.
Ann Wells, a small-ruminant veterinarian, says this new approach
to monitoring parasites loads “is one of the best tools that I've
ever seen.” Producers do have to go through training before they
can get the FAMACHA card, but veterinarians and educators can get
the cards and do training anywhere. See the Southern Consortium
for Small Ruminant Parasite Control (listed in Resources) for more
information.
