A26-Lancaster Famting, Saturday, March 6 1993
More Testing For Avian Influenza
ANDY ANDREWS
Lancaster Fanning Staff
LANCASTER (Lancaster Co.)
—Poultry producers are not being
as aggressive in testing birds in
their flocks for possible avian
influenza (AI) virus infection as
they should be, according to Dr.
Patricia Dunn, of Penn State’s vet
erinary science department, on
Thursday at the Lancaster County
Poultry Progress Day.
Dunn told the 12S poultry pro
ducers and industry representa
tives who attended the meeting
that back in 1985-1986, right after
the last severe outbreak of avian
influenza in Pennsylvania, the labs
were testing more than 15,000
samples a month. Although she
made clear that the state is not
experiencing an outbreak of clini
cal avian influenza, still, the num
bers being tested are only half of •
what they were in 1985-1986.
Only one live bird market has
tested positive in a virus isolation
of the type HSN2, and that flock
has been depopulated. Live bird
markets pose the greatest risk of
infection and spread of the virus,
according to Dunn, and of the iso
lates found, there is no evidence of
highly pathogenic strains of the
virus in any other flock in the state.
But producers should be con
cerned and follow the steps out
lined by Dunn to prevent their own
herds from becoming infected with
the virus, which is dangerous
because it can easily transform
from a harmless to a highly
pathogenic form.
Producers should remain on the
offensive, said Dunn, to prevent
what happened in the state in
1983-1984, when piles of dead
birds were the result of a massive
infection on many flocks. The
more producers know, according
to Dunn, the more they can do to
prevent possible disease outbreaks
in flocks.
The laboratories doing the test
ing ue focusing on the Type A
avian influenza virus, which has
two projections on the surface of it,
H and N, There are 14 types of H
and nine types of N that exist, she
said. But it is the combination
HSN2 which caused the prob
lems in the 1983-1984 and
1985-1986 outbreaks.
Dr. Mika HuM, poultry aeionoo department it Virginia
Tach, axplalnad a varMy of waya to ramova strata In the
growar house and management techniques producers can
use now to create a healthier bird.
The highly pathogenic avian
influenza (HPAI) type can cause
the most damage. It can readily
change (mutate) unpredictably.
Literally, with “a snap of the fin
ger,” Dunn said, it can change to
one that is benign, which has no
affect on the bird, to one that is
deadly.
According to Dunn, of particu
lar concern is the way die virus can
spread to birds. The most common
way is through wild waterfowl
near enough to flocks that are
exposed. For the virus that struck
in 1983-1984, there was a high
correlation.between the virus in
turkeys on the open range and the
closeness to waterfowl and their
breeding grounds and migration
routes.
Dunn pointed out several ways
to identify infected birds. Those
with the severe infection have
swelling or edema of the free and a
darkening of the comb. The birds
are lethargic, and the feet swell.
There may also be signs of severe
nervousness. Eventually, the cir
culatory system collapses, and the
bird dies.
The virus, once shed, can exist
in fecal material or any organic
matter for days at a time. Dunn
said that producers should be con
cerned that the virus contained in 1
gram of manure (which will fit on
the surface of a dime) can infect
one million chickens.
There are two methods used to
detect infection, according to
Dunn. One is serology, or detect
ing the presence of antibodies as a
result of the infection (this is an
indirect sign of possible presence
of the virus). The other is virus iso
late. which provides direct proof
the virus is present. The virus iso
late uses a blood sample and an
AGP lest that screens any Type A
A 1 virus. Also, the virus can be
recovered from fecal material, lit
ter, and feed material
Producers should note that the
seropositive HSN2 evidence has
been limited to less than 10 pre
mises in this region, and those pre
mises are under quarantine. The AI
virus has been detected in five
New Jersey live bird markets,
eight New York live bird markets,
and one New Jersey farm. (Dunn
noted that one farm was tested ser-
opositive but no vims his been iso
lated to date. Often times a bud can
test positive but has somehow rig
itself of evidence of the virus.)
One procedure available for
producers, according to the Penn
State scientist (who is not affiliated
with any regulatory agency), is to
contact the Pa. Dept of Agricul
ture’s Bureau of Animal industry
at (717) 783-9SSO for questions on
what they should do if they suspect
possible infection of the flock. But
first broiler, layer, or turkey pro
ducers should consider the follow
ing ways to stop the potential
spread of the virus:
• Anything that moves, includ
ing equipment vehicles, debris,
flies, rodents, or anything that can
be carried on egg flats, boxes, dead
birds, or other items, including
people and their clodies, can carry
the virus.
• Eliminate all contact with
waterfowl. Also, in a diversified
poultry area, limit contact and
movement with different bird spe
cies (turkeys with broilers, layers
with turkeys, etc.)
• Discontinue contact with live
bird markets and backyard flocks.
Avoid contact with all wild buds.
• Continue to monitor any evi
dence of the virus in your own
flock by having tests sent to the
laboratory regularly.
• Practice good biosecurity by
controlling the movement of peo
ple, poultry, and equipment. Sanit
ize properly, wear clean clothes
and boois, and make sure all equip
ment and clothing is cleaned and
sanitized properly. Scrub all
material with disinfectant before
using again.
• Continue aggressive monitor
ing of the flock through the AI
surveillance program over the long
term. Cooperate with all segments
of the industry.
Hot weather tips
While producers may not be
thinking about hot weather right
now, it is still a good time to be pre
paring for hot weather manage
ment tipt for poultry, according to
Dr. William Weaver, poultry ici
ence department, Penn State.
Weaver told the producers that a
combination of fogging and tunnel
ventilation can work together to
help cool birds over the hot sum
mer months.
Weaver examined some of the
critical aspects of ensuring proper
ventilation for poultry houses. He
examined passive ventilation,
using curtains, and fan ventilation,
which works well to move air
across the birds from one side of
the house to the other to keep them
cod.
Producers should understand
that, when the temperature outside
is 95 degrees, very seldom is the
relative humidity (RH) more than
40 percent, according to Weaver.
The higher the temperature, usual
ly lower the RH. If the RH can be
lowered, it can affect a drop in
temperature enough to keep the
birds from dying and keep them
eating.
If using a foggcr, the rule of
thumb is 9 gallons per hour for
every 1,000 square feet of cover
age. He used an example of a house
measuring 42 feet by 10 feet high.
A producer would need nine
48-inch fans to maaintain a CFM
airflow of 400.
Weaver said that the foggcr sys
tem works well for big birds as a
summertime system, but not as
well for little birds. Also, there will
be bird migration in the house
while using the system.
Needed, Says Scientist
Marilyn Holloway, Lancaster County Outstanding 4-H
member, gave her presentation on broilers and barbecues,
of which she was honored as fourth place in the nation at
the International Livestock Expo In Louisville, Ky. recently.
SE findings
Dr. David KndeL USDA, pre
sented the lastest results of the
findings of the salmonella enteridi
tis (SE) Pilot Project and lessons
learned. As of January this year,
some things about SE were known:
• SE does not appear to be clear
ly related to specific management
factors.
• The environments of S 8 per
cent of the 66 flocks enrolled have
been SE positive.
• To date, about 280,000 eggs
have been tested. In environmen
tally positive houses, positive eggs
have been found in 33 percent of
the flocks.
• Molting is being examined as
a risk factor for egg infection in
environmentally positive houses.
• Mice would appear to be a sig
nificant risk factor for introduction
of SE to a flock. Mice have been
SE positive in 78 percent of envir
onmentally positive and 29 percent
of environmentally negative
houses. Controlling mice is vital to
help eliminate SE from the flock.
• The source of SE for a flock
may be impossible to determine.
Kradel outlined the future pro
jections for the pilot project, which
included a need for a program that
would service the needs of a larger
number of flocks.
Three labs
Dr. Cy Card, Pennsylvania Ani
mal Health Commission, spoke
about the efforts to form an accre
dited system utilizing the three
laboratories in the slate Sum
merdale. New Bolton Center, and
Penn Sate and to link them
together for common technical and
testing support.
Poultry producer* are not bring at aggressive In tooting
birds In tholr flocks lor posslbis svlan Influenza (Al) virus
Infection as they should be, according to Dr. Patricia Dunn,
of Penn State’s veterinary science department, on Thurs
day at the Lancaster County Poultry Progress Day.
Eventually, the laboratories can
be linked to die state department of
agriculture to provide a wealth of
support for industry.
By the end of this month,
according to Card, a 900 computer
access number will be available to
transfer lab results and to obtain
information from the labs for
approved users. The user fee, for
those who have computers, would
be approximately $lOO per line,
with connect and other fees,
according to Card.
Dr. Mike Hulet, poultry science
department at Virginia Tech,
explained a variety of ways to
remove stress in the grower house
and management techniques pro
ducers can use now to create a
healthier bird.
Abo at the Poultry Progress
Day, Dr. Paul Patterson, Penn
State, presented a slilde tour of
Southeastern, the world’s largest
poultry show in Atlanta. Ga. Dr.
Stephen Knable, food science
department, Penn State, spoke
about on-farm egg washing to
reduce SE. And Jeff Fagan,
DeKalb, spoke about water quality
and bird performance.
Additionally, Marilyn Hollo
way. Lancaster County Outstand
ing 4-H member, gave her presen
tation on broilers sod barbecues, of
which she was honored as fourth
place in the nation at the Interna
tional Livestock Expo in Louisvil
le. Ky. Nov. 17-19.
Also, Dr. Donald Evans. Col
lege of Agricultural Sciences.
Penn State, spoke about Pennsyl
vania Agriculture, The Envy of the
World, at Poultry Progress Day.