HomeMy WebLinkAboutThe Rural Voice, 1992-02, Page 16WELLESLEY LOADING CHUTES
CATTLE CHUTES
ROUND BALE FEEDERS
1
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LOADING
CHUTE
• Heavy
Construction
A.- -"� •3pt.hitch
(both sides)
` • Ramp settings
i 26'
42'
CATTLE CHUTE
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• Heavy Duty
• 3 pt. hitch (both sides)
• Collapsible for shipping
ROUND BALE
FEEDERS
40 rirti f )
101
• 5' x 7' • Cradle design
• Feeds approx. 16 cattle
• Holds 5' x 4' bales
• Collapsible for easy shipping
TILMAN SHERK
R. R. 3, Wellesley, Ontario
519-656-3338
519-656-3429 evenings
12 THE RURAL VOICE
DIAGNOSTICS
ROUNDWORMS IN OLDER SWINE
by DR. G.K.A. JOSEPHSON
Intestinal roundworm infection in
swine, or ascariasis, has a worldwide
distribution. It is caused by the para-
site Ascaris suum, which in its adult
form can be up to 40 cm in length.
Infection is common, particularly if
pigs are allowed outside or if a de-
worming program is not followed.
Female roundworms are very pro-
lific, each laying up to 1,500,000
eggs per day; it is understandable
why a pen of pigs can become infect-
ed if exposed to even one infected
animal. Eggs are passed in the feces
and the only way an animal can be-
come infected is through ingestion of
eggs. These eggs are very resistant,
as they can survive in the soil for up
to four years.
The life cycle of the roundworm
starts with the ingestion of eggs,
which hatch in the small intestine of
the pig. The larvae emerge from the
eggs, penetrate into blood vessels and
are carried to the liver where their mi-
gration through the liver results in
damage appearing as small white
spots (milk spots) on the surface. The
larvae again enter the blood stream
and are carried to the lungs, where
they penetrate into the alveoli or air
sacs. During this stage, they cause an
inflammatory reaction resulting in
pneumonia symptoms. The tiny lar-
vae are coughed up, swallowed and
develop into mature roundworms in
the intestine.
Under normal conditions, piglets
are often infected while still nursing.
If the infection is massive, clinical
signs such as difficult breathing (call-
ed "thumps") are seen in young pig-
lets. A reduced rate of gain is noted
in pigs that are infected during the
growing stage. Signs of ascarid in-
fections are usually apparent in pigs
from 2 to 5 months of age. Preven-
tative programs that involve the rou-
tine administration of one of several
anthelmentics are routinely followed
by all swine producers.
Following exposure, a natural im-
munity occurs and the animal and its
reduced worm population seem to be
able to live together with no outward
signs of discomfort.
At the diagnostic laboratory, a
new syndrome has appeared in the
last two years. Acute respiratory
problems that do not respond to con-
ventional treatment, sudden deaths,
and the appearance of animals faring
poorly have occurred in finishing
barns and even in young gilts. The
condemnation rate of livers from fin-
ished hogs and young gilts from some
farms has increased dramatically.
Post-mortem and slaughterhouse ex-
aminations have revealed findings
that are typical of acute, massive and
overwhelming ascarid infections in
livers and lungs from these animals.
What was causing this problem in
animals that should have developed a
protective degree of immunity long
before reaching this age? Further in-
vestigation revealed that in all cases
the producers had been using a parti-
cular injectable deworming product
over several years. Typically, sows
were injected prior to farrowing as
part of a mange eradication program,
with secondary emphasis on control
of other parasites. Piglets were given
an injection soon after weaning; de-
wormers were not used in older pigs.
We feel that this product is an ex-
cellent one and that a program such as
the one above has produced a sow
herd free of roundworms (as well as
provided excellent mange control).
Since the sows and weaned piglets
are free of worms and all are being
raised on cement floors that are rout-
inely cleaned, scraped and sanitized,
the pigs are not exposed to ascarid
eggs until they reach the finishing
barns. Because of the perceived lack
of a problem, worming programs in
the finishing barns have become non-
existent. Since sanitation is not as
strict in this area, ascarid eggs are