The Rural Voice, 1992-04, Page 16r- trotp
444: Hydraulic pumps,
Valves, Cylinders &
Controls
• repair •service
• sales
BARFOOT'S WELDING
and
MACHINE SHOP
Parts & Service
• Bearings
• Shafting
• Shearing & Bending
• Castings repaired
• Cylinders re -bored & resleeved
(BwM)
WIARTON, ONT.
519-534-1200
BOLTON
FARM SEEDS
Dependable, Quality Pedigreed Seed
WHITE BEANS
SEAFARER - earliest maturing variety
available Very popular in Michigan.
OAC SEAFORTH - early. Has
resistance to anthracnose.
MITCHELL - early. Has resistance to
Alpha anthracnose.
CENTRALIA - medium maturity. Has
resistance to anthracnose and shows a
lower incidence of white mold than some
varieties. Has excellent yield potential.
OAC CYGNUS - medium maturity.
Has resistance to anthracnose.
EX RICO 23 - late maturity. Has
resistance to white mold.
OAC GRYPHON - late maturity. Has
resistance to anthracnose and low
incidence of white mold. Excellent yield
potential.
R.T. Bolton & Son
R.R. 1, Dublin, Ontario
519-527-0455 519-527-0559
At Auburn call Ralph Lubbers 526-7229
At Bluevale call Glen Warwick 357-3001
12 THE RURAL VOICE
DIAGNOSTICS
APPLICATION OF NEW DIAGNOSTIC TESTS
by S. ERNEST SANFORD
VETERINARY LABORATORY SERVICES
Last month I introduced some of
the recently developed tests currently
being used in our laboratories. I also
discussed reasons for having new
tests and gave a brief sketch of how a
few of these tests arc used. In this
issue I shall focus on one topic
(scours) and give examples of how
the new tests are used to diagnose the
cause(s) of scours.
Scouring Calves and Pigs: Several
viruses are known to
cause scours in young
(newborn) calves and
pigs. Rotavirus is one
of the most common of
the viruses causing
these scours. At the
start of the scour
outbreak (for about the
first 48 to 60 hours) the
infected animals shed
the rotavirus in the
scour material from
whence it may be
spread to neighbouring
animals who then start to scour. This
fresh scour material can be taken
directly to the laboratory and the
Rotavirus Latex Agglutination (RLA)
Test conducted on it to see if
rotavirus is the cause of the scour.
This means that the whole animal
does not have to be submitted to the
laboratory for testing.
Another type of virus causing
scours in calves and pigs is
coronavirus. In calves, the ELISA
test is used to check fresh scour
material for bovine coronavirus
(BCV). Another spin-off advantage
with the ELISA test for BCV has been
diagnosis of winter dysentery in dairy
cows. Winter dysentery has only
recently been shown to be caused by
BCV. The pig coronavirus is the
well-known TGE virus. The quick
tests used to identify TGE virus are
Ne
spee
done on intestinal tissue which still
requires submission of a live piglet
which has just started to scour. Then
the old FA test, or the new Immuno-
peroxidase (IPx) Test can be per-
formed on the tissue.
E. coli Scours: Another recent
innovation has been the expansion of
the E. coli testing pools to include
newly evolved serotypes, pili, and
verotoxin producers. This has had an
immediate impact on our
ability to identify newer
problem E. colis, most
especially in weaned pigs
and 1-2 week-old
noncoccidia pig scours.
The main differences
in these new RLA, ELISA
and IPx tests are the ease,
speed, and reduced costs
that these tests attain over
the previous tests. For
instance, in the past
rotaviruses and
coronaviruses were
identified by either (1) virus isolation,
or (2) electronmicroscopy. Both of
these techniques are highly technical,
often very challenging, time
consuming and very expensive, all
the more so if no virus is there, since
it then means that the tests are
repeated several times before a
negative answer is finally given. It
could take up to four or even five
weeks to give a negative virus answer
(paradoxically, a positive answer is
often much quicker; 1-2 weeks). The
newer tests mentioned above,
however, can be performed by any
laboratory worker, on the same day
the sample is received (time
permitting), and the answer is yes
or no, immediately! We have
already seen dramatic results since
the implementation of these newer
tests.0
w tests
cansimplify
gnosis,
d results
dia
and
redu
ce costs