{Here is a really great free sheep newsletter put
out by the Ohio State University Extension. I
contains more useful info about sheep and pasture
than I've seen in a long time. Readers can
subscribe electronically to this newsletter by
sending an e-mail message addressed to:
[EMAIL PROTECTED] A successful
subscription message will receive a reply.--Carol}
___________________________________________________
OSU Sheep Team Newsletter
May, 2008
The OSU Sheep Team Newsletter is a quarterly
newsletter produced electronically by the OSU
Sheep Team, comprised of OSU/OARDC faculty and
staff, Extension Agents, and industry representatives.
In This Issue...
A) ONE ACTIVITY IN MAY THAT CAN IMPROVE YOUR PASTURE YIELD
B) OVERVIEW OF SHEEP TEAM TRIP TO VIRGINIA/WEST VIRGINIA
C) SUDANGRASS, COULD IT WORK FOR YOU
D) BLACK VULTURE CONTROL: PART 1 THE INDEMNITY PROCESS
E) NOR-98 LIKE SCRAPIE FOUND IN THE UNITED STATES
F) OHIO SHEEP DAY
G) DIRECTIONS TO OHIO SHEEP DAY
H) INTERESTED IN HAVING YOUR LAMBS SCANNED?
A) ONE ACTIVITY IN MAY THAT CAN IMPROVE YOUR PASTURE YIELD
Jeff McCutcheon, Extension Educator, Knox County
After the dry growing season last year many sheep
producers are asking what they could do to
improve pasture yields. Other than improving
soil fertility there is one thing you can do
during the month of May that will improve
yields. In fact most experienced graziers I know
get pretty fanatical about this task. The task
is simple; remove the reproductive tillers before
they produce seed. In other words do not let your pasture plants have sex.
The reason you do not want to see reproductive
tillers is because letting the grass plants
produce seed will decrease yield. Reproductive
tillers reduce yields in two ways. First,
reproductive tillers elongate above the other
tillers on the plant and shade out the vegetative
tillers. This competition for sunlight means
that the vegetative tillers are growing
less. Less sunlight reaching the crowns of the
grass plants also means that fewer vegetative
buds on the crown will develop into
tillers. Yield in pastures is heavily influenced
by the density of the pasture. More tillers are better than more height.
The second way reproductive tillers reduce yield,
is by producing hormones as the seeds mature that
retard or inhibit the development of other
vegetative tillers. The grass plant will not
produce more vegetative growth until the seeds
completely mature or the reproductive tiller is
removed. Remember, the plant's priority is to
put its resources into the development of a
mature seed, not to grow high quality vegetative material.
When should you remove the reproductive
tillers? To keep our pastures vegetative,
reproductive tillers should be removed between
boot and flowering. During spring we have
warming temperatures with increasingly longer
days and shorter nights. Each grass plant has
multiple tillers. Initially in the spring all
the tillers produce vegetative growth. For each
grass there is a range of light to dark time
where those tillers induced to flowering when
they were developed last fall, switch from
vegetative growth to reproductive growth. The
tiller elongates and stem formation begins. The
tiller now shifts its resources to seed
development and further leaf production on the
tiller stops. The seed head develops and is
pushed up and out of the tiller. Boot stage is
when the seed head is just about ready to emerge
from the last elongated node area and is still
wrapped in a leaf sheath. After the seed head
emerges from the leaf sheath the reproduction
continues with flowering, seed development, seed growth and seed maturation.
Unlike vegetative tillers that have the growing
point near the soil surface, the growing point in
a reproductive tiller is generally found just
below the last completed node. This growing point
is vulnerable to grazing or clipping. If the
growing point is removed then re-growth will come
from the development of new tillers.
One caution, there can be more than one
reproductive tiller on a plant. Even though our
cool season grasses produce seed heads in the
spring, those tillers were actually developed
during the preceding fall. Cool season grasses
require a period of cold temperature with long
nights to develop flower buds on the crown of the
plant. Once reproductive growth is initiated in
the spring, one reproductive tiller will
dominate. If reproductive tillers are removed
and light conditions are still right to initiate
reproductive growth another tiller initiated last
fall will start reproductive growth. I have seen
orchardgrass three inches tall with a flowering seed head.
Because of this some sheep producers may want to
wait until most of the reproductive tillers have
developed seed heads before clipping later in the
grazing season. You could wait but you will lose
yield. Two of my colleagues have said that
clipping after flowering is either cosmetic or
for revenge, not to stimulate vegetative growth.
Every tiller on a grass plant is not a
reproductive tiller. Only those tillers induced
the preceding fall have the capacity to produce a
stem and seed head; the new tillers developed in
the early spring will not produce a seed
head. Eventually the light conditions will
change, no longer initiating reproductive growth,
and all the growth for the rest of the year will be vegetative.
Removing reproductive tillers can be accomplished
with grazing livestock or mowing. Livestock can
best do this with high stocking densities and
moving livestock quickly from one paddock to the
next. The goal is to use the livestock to just
graze the top couple of inches of the grass. To
effectively do this a heavy stocking density and
small paddock size is needed. If the grass is
not grazed uniformly enough to avoid seed head
formation, then some mechanical clipping will be needed.
B) OHIO STATE UNIVERSITY EXTENSION SHEEP TEAM
VISIT TO VIRGINIA TECH, BEAVER WEST VIRGINIA
Gary Wilson, Extension Educator, Hancock County;
Jonah Johnson, Extension Educator, Clark County;
Woody Joslin, Extension Program Assistant, Shelby
County; and Tim Fine Extension Program Assistant, Miami County
In September 2007, the OSU Extension Sheep Team
traveled to Virginia Polytechnic Institute in
Blacksburg, Virginia to observe current, cutting
edge research in sheep production. The ten team
members making the trip included producer and
industry leaders in addition to Extension
staff. Virginia Tech is one of the leading Land
Grant Universities the nation that is very
fortunate to have a strong faculty of research
professors that lead the way with expected
progeny difference (EPDs) work, determining
inherit traits, as well as determining parasite
resistance among sheep and goat breeds. The
Sheep Team was also fortunate to tour the USDAs
Appalachian Farming Systems Research Center in West Virginia.
A majority of this educational experience
occurred at the Animal Sciences facilities at
Virginia Tech. After a brief tour of the
facilities, the group was introduced to Dr. David
Notter, his research associates, as well as an
introduction to the research being conducted at
the research center. Research projects included
using ultrasound to determine genetic
inheritability traits, determining parasite
resistance across various breeds of sheep and
goats, and using various genetics to procure out-of-season breeding.
Following the Virginia Tech research tour, the
OSU Extension Sheep team spent the day at the
USDA-ARS research center in Beaver, West
Virginia. A majority of the research conducted
here is focused on forage production,
specifically annual and perennial forages, and
how different production practices maximized the
species ability to succeed into extended
grazing periods. Other research being conducted
on the Station is parasite resistance work within
goat herds to examine different parasite loads
among different forage grazing situations. One
other area of interest was managing forest areas,
where producers manage a forest for timber but
also use the grass available in these areas to graze livestock.
C) SUDANGRASS, COULD IT WORK FOR YOU?
Rory Lewandowski, Extension Educator, Athens County
Raising sheep within a pasture based production
system presents the manager with two challenges;
internal parasite control and summer slump
production of cool season pastures. The use of a
warm season annual like sudangrass may offer the
pasture based sheep producer a parasite control
option while at the same time filling in the
forage production slump demonstrated by cool
season pastures during the hot summer months. In
this article, Ill draw on some of the results
and lessons learned using sudangrass during the
summer of 2007 on the Curt Cline farm in Athens County.
The internal parasite of major concern to pasture
based sheep producers is the barber pole worm,
Haemonchus contortus. Resistance to all
classes of chemical de-wormer currently on the
market has been documented in Haemonchus
contortus populations in various farms around
Ohio. The prudent sheep producer will therefore
limit the use of chemical de-wormers and place
emphasis on controlling parasite infections
through a better understanding of parasite
biology and corresponding pasture management. A
key concept is the use of safe pastures. A safe
pasture contains no, or very low levels of,
infective Haemonchus contortus larvae. This can
be achieved by keeping sheep off a pasture for a
period of time so that there is minimal survival
of parasite larvae, or by planting an annual
forage where larvae do not survive.
Under typical cool season pasture conditions the
population of infective Haemonchus contortus
larvae continues to build from the start of
spring grazing. By mid to late summer, after
several rotations through pasture paddocks,
levels of infective larvae can be extremely high
and grazing lambs and milking ewes can quickly
pick up levels that at best suppress production
and gain, and at worst, can be fatal. At the
same time that lambs and ewes are under stress
from parasite infection, pasture quality and
quantity is decreasing. In this situation a warm
season annual forage like sudangrass can make a
real difference. In addition to acting as a safe
pasture where parasite burdens are not increased,
under hot summer conditions these forages will
continue to grow and produce a high quality feedstuff.
In 2007, as part of an on-farm study
investigating the use of alternative forages as a
control option for internal parasites, a brown
mid-rib (BMR) sudangrass from Ampac Seed Company
was planted on the Curt Cline farm in Athens
County. BMR sudangrass is more palatable and
produces a higher quality forage compared to a
non-BMR sudangrass. Trials in other states had
shown very good animal gains on this forage.
The field was seeded on June 1 at a rate of 25
lbs/acre. Since our 2007 trial, I have spoken
with Ampac seed representatives and they are
currently recommending a seeding rate for grazing
conditions of 35 lbs/acre. The field had been in
winter rye and was tilled using a chisel plow and
disk. Seed was applied with a broadcast seeder
mounted on a 4-wheeler and then cultipacked. The
seedbed was very dry. Soil fertility on this
field was at low to moderate levels with a soil
pH slightly below 6.0. According to the Ohio
Agronomy Guide, soil fertility levels should be
similar to what is needed to produce a 100-to
150-bushels/acre-corn crop. This translates into
a critical soil phosphorus level of 15 ppm and a
soil potassium level of 100 ppm at a cation
exchange capacity of 10. Following a grass sod,
nitrogen requirements range from 60 lbs/acre for
a 3-4 ton yield goal to 100 lbs/acre for a 5-6
ton yield goal. Seed should be planted one-half
to one inch deep on a firm seedbed. Recommended
planting time is from late May until the end of
June. Soil temperature should be in the 60 to 65 degree F range.
Rain was in short supply in 2007 and the prepared
seedbed was too dry initially for the BMR
sudangrass seed to germinate. On June 4 a
quarter inch of rainfall provided enough moisture
for seed germination. Fortunately, an isolated
thunderstorm brought 1.3 inches of rain to the
farm on June 9-10. From this point on the BMR
sudangrass made rapid growth. On July 12,
several days before the first grazing pass with
lambs was begun, random samples were collected
from the field, and a dry matter yield was
calculated at 3000 lbs/acre. By the time the
lambs were turned into the field several days
later, some additional growth had occurred and
the field averaged about 40 inches in height. We
recognized that grazing should have begun
earlier, but due to other conditions of the
study, this was when lambs had to start the
grazing pass. According to both the Ohio
Agronomy Guide and the Ampac Seed literature,
grazing should start at between 24 to 30 inches
in height, and be grazed down to a 6 to 8 inch stubble.
Even though lambs began grazing the BMR
sudangrass later than recommended, quality
samples collected on July 16, the day the lambs
entered the field, came back from the lab with an
analysis of 20% crude protein and 68% TDN. This
quantity and quality of forage was produced
during a period with limited rainfall and daytime
temperatures in the 90s. During this same
period cool season grass pastures were shutting
down, recording low levels of dry matter accumulation.
Something that producers need to consider
regarding a warm season annual like sudangrass is
how to best utilize the production capacity of
the forage. Since the forage grows rapidly, it
is similar to managing the spring flush of cool
season pasture growth. It is very easy for the
forage to get ahead of animal consumption,
leaving a field of mature, declining quality
forage. This happened to us at the Cline farm,
and half the BMR sudangrass field was fenced off
and cut for hay when it became apparent that
there was more forage than could be consumed in a
timely manner by the number of livestock available to graze.
The Ohio Agronomy Guide says that when a 6-8 inch
stubble is left, plants should re-grow to the 24
to 30 inch grazing height in 2 to 3 weeks. This
is consistent with what was observed on the Cline
farm. So, getting back to a management strategy
to best utilize the forage quantity being
produced, while also taking advantage of the high
quality that is possible, the producer may want
to consider staggered plantings of the sudangrass
at 2 week intervals, or plan to do a cutting for
hay or silage on part of the acreage. A sample
planning calculation might look something like
this: Sudangrass at 24-30 inches of height
producing 2500 lbs of dry matter (DM)/acre. Ewes
at 170 lbs consuming 3% of body weight per day
need 5.1 lbs of DM. If the field is strip
grazed, forage utilization should be at least
70%, so 2500 lbs of DM x .70 = 1750 lbs of DM
available. If we want a 2 week grazing period,
this will allot 125 lbs of DM / day, so we could
graze 25 ewes/acre for 14 days. If 70-pound
lambs were the grazing animals, and we figure dry
matter consumption at 4% of body weight, then 45
lambs could be grazed on this acre for 2
weeks. If we had staggered planted a second acre
of sudangrass 2 weeks after the first, or
harvested the second acre as stored forage when
grazing started, it would now be ready for a
grazing pass. In reality, because the sudangrass
will continue to grow and add dry matter from the
time the grazing pass is begun, more animals will
be needed to keep ahead of forage
growth. However, this example illustrates the
potential available during a time when forage is generally in short supply.
In addition to the forage production supplied by
the BMR sudangrass, it also provides a safe
pasture free from infective parasite larvae. The
process involved in establishing the sudangrass
destroys any larvae that might have been present
if a previously grazed sod is used. Based on the
experience at the Cline farm, even if infected
sheep/lambs are moved on to the sudangrass, the
shed eggs and resulting infective larvae are
unlikely to add to the worm burden of grazing
animals in subsequent grazing passes because: 1)
leaving a 6 to 8 inch stubble insures no, or very
few larvae will be ingested as typically
infective larvae are found on the first 3 inches
of grass plants, and 2) the structure and spacing
of sudangrass stems will make it difficult for
larvae that hatch from eggs in the feces to cover
the distance needed to crawl up stems.
During the course of the study on the Cline farm
it was found that while lambs were grazing with
their mothers they had developed high levels of
parasites. It was later discovered that the
parasite population on the farm had resistance to
all chemical de-wormers except for
Cydectin. This was not documented until late in
the season, shortly before beginning the second
grazing pass on the BMR sudangrass on August
21. As a result, lambs maintained high parasite
numbers for most of the project. While many of
the lambs demonstrated resilience to these high
parasite numbers as indicated by FAMACHA eyelid
scores of 1 and 2, performance still
suffered. As an example, just before the lambs
entered the BMR sudangrass on August 21, lambs
scoring a 3 or higher on the FAMACHA eyelid
scorecard were de-wormed using Cydectin as a
rescue treatment. This amounted to 7 lambs out
of the 20-lamb study group. The remaining 13
lambs were not treated. At the end of a 3-week
grazing pass on the BMR sudangrass, the untreated
lambs had gained 0.19 lbs/day, while the treated lambs had gained 0.42 lbs/day.
There are several lessons here. One is that
early season pasture management is critical to
avoid loading up ewes and lambs with high
parasite burdens. Two, make sure you know what
chemical de-wormers really work in your
flock. Finally, a warm season annual like
sudangrass can provide a high quality forage when
cool season pastures are declining, but that
quality is put to best use in terms of animal
performance when heavy parasite loads do not stress animals.
In summary, a warm season annual like BMR
sudangrass can be used to provide a safe pasture
while producing good tonnage and good quality
during a time cool season pastures have little
growth. To most effectively utilize this forage,
a producer must have a plan to manage the rapid
growth, including adequate animal numbers, strip
grazing, staggered plantings and/or the capacity to harvest surplus growth.
D) BLACK VULTURE CONTROL: PART 1 THE INDEMNITY PROCESS
Jeff Pelc, Wildlife Biologist USDA/APHIS,
Wildlife Services, Tim Fine, Extension Program Assistant, Miami County
Black Vultures have become a serious sheep pest
in certain areas of Ohio. This article will
focus on the procedures necessary to report a
predation loss by black vultures to the Ohio
Department of Agriculture (ODA) for reimbursement
under the indemnity program. In the next sheep
team newsletter, we will take a look at options for black vulture control.
There are certain procedural steps that must be
followed when dealing with losses due to Black
Vulture predation. In most cases, if these
procedures are not followed, compensation by ODA
for your losses may not be granted.
1. Notify your local dog warden by
telephone within 72 hours after the loss or
injury has been discovered. The dog warden shall
promptly visit your farm to determine whether the
kill was by a predator or not. If the dog warden
determines that the kill was not by a predator
then no further steps need to be taken as there
is no claim under the ODA indemnity program.
2. Document, by photograph, the injuries
sustained by the animal. This should be done
immediately after contacting the dog warden. Do
not wait for the determination as to whether the
kill was by a predator or not. It is advised to
leave the animal where it lay for investigative purposes.
3. Obtain an indemnification form from the
dog warden. This form will need to be filled out
and sent to ODA within 30 days of discovery of
the animal by the owner. Photos taken of the
injuries and any other pertinent facts shall
accompany this document. You may request
assistance from the dog warden in filling out the
indemnification form. If the animal injured or
killed is a registered animal, then registration
papers should also accompany the indemnification form.
4. If the dog warden determines that the
kill was by a predator then he/she must promptly
contact by telephone the countys wildlife officer.
5. Following the notification from the dog
warden, the wildlife officer must confirm,
disaffirm, or state that he/she is uncertain
about the determination of the dog warden on the
claim. If the wildlife officer disaffirms the
claim of the dog warden, the owner has no claim
under the ODA indemnity program
6. If the wildlife officer affirms or
states that he/she is uncertain about the
determination of the dog warden, the wildlife
officer must notify the ODA, in writing, of his/her determination.
7. The ODA will hear claims that are
approved by the dog warden and supported by the
wildlife officer. The ODA may decide to grant
full compensation, partial compensation, or no compensation.
8. If the owner feels that the ODAs
determination of the fair market value, he/she may appeal the determination.
For more information on the indemnity process,
contact the Ohio Department of Agriculture at
614-728-6220 or at
<http://www.ohioagriculture.gov/animal>http://www.ohioagriculture.gov/animal,
or contact USDA/APHIS at 614-861-8607 or on the
web at <http://www.aphis.usda.gov/ws/>http://www.aphis.usda.gov/ws/ .
E) NOR-98 LIKE SCRAPIE FOUND IN THE UNITED STATES
Becky Talley, Sheep Industry News Associate Editor
In February of last year, the U.S. Department of
Agricultures (USDA) Animal and Plant Health
Inspection Service (APHIS) officially announced
the discovery of a Nor98-like scrapie case in a
ewe from a flock in Wyoming. This was the first
case of scrapie consistent with Nor98 discovered in the United States.
Since then, four more cases have been discovered
that originated from flocks in Colorado, Indiana,
Minnesota and California. These cases are not
related to either the first one in Wyoming or to each other.
This scrapie type was first found in Norway in
1998 and has since been found in sheep and goats in many countries in Europe.
It does affect goats, says Diane Sutton, DVM,
national scrapie coordinator for USDA. So far
not here in the United States, but chances are,
we might eventually see it in goats here too.
This type of scrapie affects sheep of all
commonly occurring genotypes including those that
are resistant to classical scrapie.
According to Sutton, those flocks in the United
States that are found to be infected with
Nor98-like scrapie will not be able to use the
current genetic-base approach to flock clean up.
Producers whose flocks have risk factors for
classical scrapie are still encouraged to test at
codon 171 for classical scrapie resistance, as has been done in the past.
The World Organization for Animal Health (OIE)
has formed an ad hoc committee to consider how to
address Nor98-like scrapie with respect to trade.
It will likely be at least two years before a
code change could be made should a consensus be reached.
Until research provides us with other options
for eliminating Nor98-like scrapie and the
international community reaches a consensus on
guidelines for trade we will continue to use
flock depopulation and exposure-based clean up
plans for Nor98-like scrapie affected flocks,
says Sutton. As other viable options are
identified, we will evaluate them using pilot projects.
According to Linda Detwiler, DVM, assistant
director, Center for Public and Corporate
Veterinary Medicine, it is important to note that
it isnt known if the appearance of non-classical
scrapie cases in Europe and the United States are
more likely due to the increased ability to test
for and detect non-classical scrapie than to
increasing rates of infection. Scientists in
European countries are beginning to look at
archived samples in an attempt to identify
non-classical cases that may have occurred earlier than 1998.
I would caution everyone that its premature to
be able to say much of anything about these non-
classical cases. At this point in time, there are
many unknowns such as: 1) is there more than one
strain, 2) what is the origin, 3) are there
natural modes of transmission, 4) does the
genotype affect incubation time and clinical
presentation, 5) do codons other than 136, 141,
154 and 171 influence these cases and 6) how long
have these cases been occurring? she questions.
Because of Europes increased awareness of
non-classical scrapie, there has been quite a bit
of research into understanding how and if the
disease is transmitted and how it affects
sheep. Research is currently underway in the United States.
The first U.S. material became available in
February, so ARS (Agricultural Research Service)
is gearing up to study it. But, because of the
nature and long-term aspects of the disease, it
will take a while to study, so we will probably
be seeing research from Europe published first, Sutton adds.
In the meantime, it is stressed that officials
will continue to handle the disease as it has in
the past, and that producers should be aware of
Nor98-like scrapie but not alarmed.
We are going to treat it as scrapie until the
international community removes it as a trade
barrier or science finds that there is a better
way to handle it than the current system, Sutton says.
Jim Logans, DVM, chair of ASIs Animal Health
Committee, best advice to producers to protect
their flock from Nor98-like scrapie is to
maintain a closed ewe flock. He says that to
prevent the introduction of all scrapie types,
producers need to be aware of where new purchases
are coming from, know the genetics of new
purchases and avoid purchasing ewes unless
familiar with the scrapie status of the farm of
origin or maintain a closed ewe
flock. Essentially, people need to use common
sense and maintain good sanitation and husbandry practices,he explains.
The Science Behind Nor98 in Sheep
Nor98 is a relatively common prion disease or
transmissible spongiform encephalopathy of sheep.
The first descriptions of the disorder were in
sheep diagnosed in 1998 in Norway, although a
retrospective study has revealed a case in
England in 1989. Improved methods for diagnostic
testing were published in 2002 and surveillance
was initiated in many European countries. Most
cases are identified in clinically normal sheep
tested in routine slaughter surveillance. The
disease is experimentally transmissible to sheep
and genetically altered mice by inoculation into
their brains but no data are yet available on
whether the disease is transmitted between sheep in an affected flock.
CLINICAL SIGNS
Most cases have been discovered in clinically
normal sheep tested at slaughter. Of the few
clinical cases, a common sign is progressive
incoordination (ataxia), occurring most likely
because the abnormal prions accumulate in the
cerebellum, the region of the brain (the
cerebellum) that integrates information coming in
from the senses with nerve impulses going to the muscles.
DIAGNOSIS
Both classical scrapie and Nor98-like scrapie are
characterized by accumulation of abnormal prion
proteins. However, the distribution of the prion
proteins differ. In classical scrapie, prions are
usually found earliest in the lymph nodes and
later in the region of the brain associated with
innervation of the gut. As discussed above,
abnormal prions are found in different areas of
the brain in cases of Nor98. Further, prion
proteins are not found in the lymph nodes of
sheep with Nor98 and the current live animal
tests of lymphoid tissues are not suitable. Nor98
is a challenging diagnosis but skilled
pathologists, working with a panel of three
different diagnostic tests, can accurately
diagnose the disease in the brain of affected sheep.
GENETICS
Susceptibility to classical scrapie is associated
with naturally occurring differences in the gene
for the prion protein, particularly differences
at position 136 and 171. Each sheep has two
copies of this gene and commercially available
genotype tests show the differences at those
positions. Sheep with the genotypes 136VV 171QQ
and 136AV 171QQ are very susceptible to classical
scrapie strains. Sheep with the 136AA 171QQ
genotype are susceptible to the most common
classical scrapie strain in the United States and
represent the most common genotype found in U.S.
scrapie cases. Sheep with at least one copy of
the gene 136A 171R are generally resistant to the
more common type of classical scrapie.
Although no genotype is considered to be
resistant to Nor98-like scrapie, the disorder is
found most frequently in sheep with changes in
positions 141 and/or 154. The genetic signature
AFRQ indicates a sheep with 136A and 171Q with
the additional change to F at 141. The
signature AHQ indicates a sheep with 136A and
171Q with a change to H at position 154. A
large survey of 4,000 sheep in Europe and
numerous reports on smaller study populations has
demonstrated that sheep with either the AFRQ or
the AHQ gene were eight to 15 times more likely
to be diagnosed with Nor98-like scrapie than were
sheep with the most common genotype ARQ. Sheep
with both changes were more than 20 times more
likely to be diagnosed with Nor98-like scrapie.
Sheep with the 171R form of the gene are
generally resistant to classical scrapie but are
susceptible to Nor98-like scrapie, particularly
in 171QR sheep that have an AFRQ gene.
EPIDEMIOLOGY
Classical scrapie is usually found in more than
one sheep in a flock, with prevalence as high as
30 percent with some scrapie strains. In
contrast, more than one sheep with Nor98-like
scrapie is usually found only in flocks of more
than 500 sheep. In addition to genotype, age
appears to represent a significant risk factor
for Nor98-like scrapie. In the large European
study, 80 percent of the cases of classical
scrapie were found in sheep ages 3-5, a finding
similar to that reported in the US. In contrast,
more than 60 percent of the sheep with Nor98-like
scrapie were older than five years and more than
25 percent were more than 10 years old. Nor98 is
found in most countries performing large-scale
surveillance; the disorder occurs at a rate of
approximately one in 1,400 mature sheep at
slaughter even if the rate of classical scrapie is very low.
The low prevalence of Nor98 within flocks, the
wide geographic distribution of the disorder, the
range in age of onset or diagnosis, and the
genetic factors increasing the risk of Nor98 are
strikingly different than those found in
classical scrapie. There may be additional
genetic factors influencing development of this
disorder, in addition to factors such as route of
infection or age at which sheep are infected.
Alternatively, Nor98 may be a sporadic disease of
sheep, appearing primarily but not exclusively in
older sheep. Additional findings from
experimental studies and large scale surveillance
using improved diagnostic methods will be useful
in understanding this wide-spread prion disease of sheep.
BACKGROUND INFORMATION
Luhken and others, 2007, Veterinary Research 38: 65-80.
Bruce and others, 2007, Veterinary Record 160: 665-666.
Benestad and others, 2003, Veterinary Record 153: 202-208.
F) OHIO SHEEP DAY IS SET
Rory Lewandowski, Extension Educator Athens County
Ohio Sheep Day is scheduled for Saturday, July
12. It will be held on the Cline family farm,
located just outside of Albany Ohio in Athens
County. Curt Cline was the 2007 Ohio Sheep
Improvement Association Environmental Stewardship
Award winner and at the recent American Sheep
Industry meeting was named the national
Environmental Stewardship Award winner. Curt is
currently serving as a director on the board of
the Ohio Sheep Improvement Association.
Curt and Wendy Cline run a forage based sheep
operation and are currently undergoing an
expansion of their sheep flock that will take
them from 120 ewes to 300 plus ewes by the time
Sheep Day arrives. The expansion is the result
of some significant management changes that
revolve around internal parasite control, more
intensive use of traditional and alternative
forages and the economic potential of the Ohio
sheep industry. Visitors to the Cline farm
during Sheep Day can expect to hear about the
importance of economic analysis as a base to decision making.
The 2008 Sheep Day at the Cline farm will focus
on forage demonstrations, grazing management and
stored forage use. A partial list of what visitors will see includes:
* Fall (2007) seeded grass plots
* Fall (2007) seed grass plots frost
seeded in late winter 2008 with red and white clover
* A Tekapo orchardgrass field
established in 2004, interseeded/frost seeded in
late winter of 2008 with red and white clover,
using grazing sheep to insure good seed/soil contact
* Forage chicory field
* Several fields of Brown Mid-Rib
(BMR) sudangrass and sorghum x sudangrass hybrids being strip grazed by sheep
* Surplus BMR sudangrass and sorghum
x sudangrass forage harvested/chopped and stored in silage bags
* Paddock and water system for cool season grass pastures
In addition to talking about the agronomic
characteristics of forages used on the farm,
other topics that will be addressed include:
* Soil fertility management using
grid sampling and GIS fertilizer application on pasture paddocks
* Internal parasite management within a rotational grazing system
* Handling and caring for foot rot
* Economic issues and considerations
in a forage based sheep operation
* Utilizing cost-share assistance
programs like EQIP to protect the environment and improve grazing management
There will also be vendors/exhibitors dealing
with all aspects of sheep production.
Ohio Sheep Day will offer
visitors the opportunity to visit a farm that has
been in the Cline family since the late 1800s
where today 3 generations come together to live
and work. Curt and Wendy are excited about the
future of agriculture and the opportunities for
profit that a sheep operation can
generate. Sheep owners and anyone interested in
forage management is cordially invited to Ohio
Sheep Day at the Cline farm in scenic Athens County.
Dont forget to mark your
calendars for July 11 as well as once again the
Ohio Forage and Grassland Council will be
sponsoring a pre-Sheep Day tour of some area farms. More details will follow.
G) DIRECTIONS TO THE CLINE FARM; SITE FOR OHIO SHEEP DAY
Rory Lewandowski, Extension Educator, Athens County
From Columbus take U.S. 33 East to Athens and
then SR 32/50 West to Albany. At the traffic
light in Albany turn right, go past the Marathon
gas station down to Lee Street. Turn right on to
Lee Street (Hocking Valley Bank on the corner),
go 1 block and then turn right on to SR 681. Go
approximately a quarter of a mile and turn left
on to Factory Road. Go 1.25 miles on Factory Rd
to 3933 Factory Rd and you have arrived at the Cline Family farm.
H) INTERESTED IN HAVING YOUR LAMBS SCANNED FOR LOIN EYE SIZE AND BACKFAT?
Bill and Susan Shultz, Sheep Producers in Logan County
Bill and Susan Shultz will be scanning their 2008
lamb crop on Friday, June 13, 2008 at their farm
at DeGraff, Ohio. They have contracted with
Bonnie Bradford, a skilled technician, to do the
scanning of loin eye and back fat as she has done
the past three years for the Shultzs.
For any sheep breeder who is interested in
scanning their lambs, the Shultzs are willing
for you to bring your lambs to their farm during
the late morning on the 13th. Due to health
concerns all lambs will need to be unloaded,
processed and reloaded onto the truck or trailer
as there will be no penning of animals at the
site. The procedure for scanning is that a
weighing scale will be available, and personnel
will be available to shear each lamb between the
12th and 13th rib to provide adequate contact for
the scanner. Bonnie charges $5.00 per head for scanning.
If you are interested in scanning lambs please
contact Bill or Susan at 937-585-6626 or
<mailto:[EMAIL PROTECTED]>[EMAIL PROTECTED]
and they will schedule you in for the morning of June 13th.
Where tables are included every effort is made to
transmit the tables intact. Due to the setup of
different e-mail receiving programs tables may
not be readable due to shifts in lines and font
sizes etc. Readers can visit our web site when
table formats are unreadable. The newsletter will
be posted on the web site at:
<http://knox-cms.ag.ohio-state.edu/agriculture/livestock/sheep/sheep-team-newsletter/sheep-team-newsletter-default>http://knox-cms.ag.ohio-state.edu/agriculture/livestock/sheep/sheep-team-newsletter/sheep-team-newsletter-default
Readers can subscribe electronically to this
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subscription message will receive a reply.
Contact your local Ohio State University
Extension Office or e-mail [EMAIL PROTECTED]
if you have problems subscribing.
Editor: Tim Fine
Information presented above and where trade names
are used, they are supplied with the
understanding that no discrimination is intended
and no endorsement by Ohio State University
Extension is implied. Although every attempt is
made to produce information that is complete,
timely, and accurate, the pesticide/drug user
bears responsibility of consulting the label and adhering to those directions.
All educational programs conducted by Ohio State
University Extension are available to clientele
on a nondiscriminatory basis without regard to
race, color, creed, religion, sexual orientation,
national origin, gender, age, disability or Vietnam-era veteran status.
Issued in furtherance of Cooperative Extension
work, Acts of May 8 and June 30, 1914, in
cooperation with the U.S. Department of
Agriculture, Keith L. Smith, Director, Ohio State
University Extension. TDD # 1 (800) 589-8292 (Ohio only) or (614) 292-1868
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