The Rural Voice, 1991-07, Page 20cI1n.con'
WtEm3
HAY
FEEDERS
Round Bale Hay Feeder
7' diam. x 4' high
available with 1" - 1 1/4" or
1 1/2" square tubing
Collapsible Hay Saver
• fits inside most round hay feeders
• fodder stays inside feeder instead
of being trampled underfoot
A division of Steve's Welding
R R 1, Newton, Ont. NOK 1R0
519-595-8737
VENTILATION
/ /
AXIS -AIR
BLENDER
lid
Uniform Temperature
Reduces Drafts
• Automatic System
Easy Maintenance
Corrosion Resistant
SERVICE for Martin -Air
PHONE 519-345-2258
AXIS PRODUCTS LTD.,
5 Main Street,
Rrodhagcn, Ontario
Canada NOK 1130
Dealer enquiries welcome
16 THE RURAL VOCE
DIAGNOSTICS
PARASITISM IN RUMINANTS
by DR. A. J. REHMTULLA
VETERINARY LABORATORY SERVICES
With the onset of warm humid
conditions, problems such as internal
parasites become more prevalent, par-
ticularly in pastured animals, unless a
rigid worm control program is fol-
lowed.
In our arca of southern Ontario,
parasites commonly found in cattle,
sheep, and goats, arc roundworms,
lungworms, and tapeworms. Of these,
the tapeworms (Moneizia), though im-
pressive due to their visibility, length,
and numbers, are usually not a prob-
lem. Roundworms and lungworms,
however, can cause major difficulties
if not properly controlled, particularly
in young stock.
In general, most worms are
"picked up" while grazing (that is,
they do not multiply in the animals
like bacteria and viruses do). It may
be assumed that all pastured animals
have worms, though they may not
show any adverse effects clinically,
while continuing to contaminate the
pastures via manure dispersal, at a
very low level.
Depending on their type, adult
worms live in the stomach (Ilaemon-
chus, Ostertagia) small intestines
(Cooperia, Nematodirus), large intes-
tines (Oesophagostomum, Trichuris)
or lungs (Dictyocaulus, Mullerius).
These worms are commonly referred
to as stomach worms, threadworms,
nodular worms, wireworms, whip-
worms, lungworms, etc.
In their digestive tracts, the larvae
mature to adults and then produce
eggs which are shed in their manure.
Larvae hatch out of these eggs and
wait in the grass which livestock pick
up at grazing, thereby completing the
cycle. (Lungworm larvae, however,
after being ingested, penetrate the wall
of the intestine, eventually enter the
bloodstream, and get carried to the
lungs, where they develop into adults
in the bronchi [branches of the wind-
pipe]. They produce eggs which hatch
into larvae which are coughed up and
swallowed and are eventually shed in
manure.)
It is when the "worm burden"
becomes overwhelming that animals
show clinical signs, depending upon
the type of parasites and their num-
bers. The signs also vary depending
upon the resistance of the animal,
hence generally the young stock are
most vulnerable. The signs include
scouring, loss of weight, unthriftiness,
dehydration, anemia, and dependent
edema (fluid accumulation under jaws,
brisket, belly). Occasionally a young
animal might be found suddenly dead
on pasture due to severe parasitism.
Diagnosis of a worm problem is
usually made by finding eggs or larvae
in fecal samples or at necropsy. When
a parasite problem is identified, it is
vital for the producer to work with his/
her veterinarian to devise a strategic
deworming program, since an accurate
assessment of the burden is a
combination of many factors. What
classes of animals are affected? How
severe are the signs? What type of
parasites are present? What is the
cycle of this particular parasite? The
method of handling each outbreak will
vary according to these circumstances,
and particularly the climatic season.
There are many dewormers avail-
able in the marketplace. The right
medication would depend upon the
combination of circumstances having
considered season, calving/lambing
time, worm burden, management
system, and clinical status of animals.
Hence it is far beuer to institute a
complete and strategic deworming
program with your veterinarian, and
resist the temptation of reaching for
the nearest dewormer. Usually such
"one-shot" deals provide only short
term solutions. In the long run, the
worm problem will linger on, due to
reinfection, and become far more
difficult to handle. As with any good
management practice, following de-
worming, livestock should be moved
to clean pastures, and the herd or flock
should remain on a worm control
program over subsequent scasons.0
We invite you to tour the Diagnostic
Laboratory at Huron Park — call
ahead 228-6691, Ext. 276.