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The
New Scrapie Rule By
Tom Boyer January
2001 The National Scrapie Oversight Board recently was involved
in a conference call wherein the Draft Scrapie Eradication UM&R was
discussed. The UM&R will be the
field guide that supports the forthcoming Scrapie rule.
Being a new member of that board, I would like to give an update of how I
see the new rule impacting the sheep and goat industries.
First I will give a brief history for those who may not be familiar with
the disease. Scrapie has been reported worldwide and affects most sheep
producing regions with few notable exceptions. The disease has been recognized for over two centuries in
England, Wales and Germany. The
disease has been for the most part, a mystery not only in origin, but also in
transmission as well as eradication. The
discovery of Bovine Spongiform Encephalopathy (BSE) and the new variant of
Creutzfeldt-Jakob disease (nvCJD) have resulted in a resurgence of scrapie
research not only in Europe but also around the world.
The disease appeared in English Suffolk sheep and between 1920 and 1950
caused substantial financial losses. The
disease appears most often in animals between two and five years of age.
While the exact means of transmission is unknown; lateral transmission
can occur. Placenta has been shown
to contain the infectious agent and transmission is highest when young animals
are exposed at or near birth. The
extent to which scrapie is transmitted by exposure to contaminated environment,
including pens, barns, feed water, bedding and related means is unknown.
Vertical transmission through embryos is not conclusive, thus you cannot
be certain whether there may be a problem of passing the disease by this means
or not as there is conflicting research regarding this means of transmission. It is believed that there is a high probability that the
disease is spread from mother to offspring through the reproductive process.
It is also thought that the ram or buck plays little or no role in the
actual transmission of scrapie. The
transmission of scrapie is like an unfinished puzzle.
There are several pieces many of which are unconnected, but no full
picture is in sight. The disease
affects nerve cells and thus affected animals will usually show behavioral
changes, tremor (especially of head and neck), pruritus and locomotor in
coordination which progresses to the death of the animal.
The course of the disease will usually take from one to six months.
The onset of clinical signs often starts with a slight change in
behavior, wherein the animal becomes more nervous or aggressive and may separate
themselves from the rest of the flock. Some sheep appear to be demented and have been observed head
pressing or ‘star gazing’. Hypersensitivity
is another characteristic where the animal may appear normal if left
undisturbed, but when stimulated by a sudden noise or excessive movement they
may fall down and go into a convulsive state.
Scrapie acquired its name from the feature of sheep rubbing themselves
against fixed objects. They may rub until not only is all the wool gone, but also
the area may be raw. Goats are less
likely to rub against fixed objects, rather they will scratch vigorously with
hind feet and horns. Motor
abnormalities often include a high stepping gait of the forelimbs and a ‘bunny
hop’ movement of the back legs. This
gait is exaggerated when the animal is made to run.
These processes increase until the animal may need a fence for support
when standing and have difficulty in rising.
Not all animals will exhibit all signs of the disease and there may be
differences between breeds and between sheep and goats.
The disease can only be clinically identified at this point by examining
gray material from the brain stem. Thus
there is no live animal test at the present time.
(Based on the aforementioned symptoms, Carrie has requested that I get
some of my few gray cells examined). A
great deal of research has been conducted to determine if the disease is more
prevalent in certain genetic combinations.
To this point in time, the research is inconclusive, leaving only
statistical analysis for theoretical conclusions.
From statistics, we know that the disease is more prevalent in blackface
sheep than in whiteface breeds. We
also know that the disease is much more prevalent in sheep than in goats.
There have been cases diagnosed in goats and thus they are included in
both the research as well as the forthcoming scrapie program.
The only known control of the disease is burial of animals.
Having given the previous history, you may well be more
confused than clear on most facets of the disease. Truly, Scrapie is a mystery disease that may well affect us,
as sheep and goat producers, more by the unknown than by the known.
Certainly, the forthcoming program will affect the sheep and goat world.
While the particulars of the program have not been finalized, as
mentioned previously, I was involved in a conference call wherein a producer
committee was allowed to comment on the proposed program implementation plan
(Draft Scrapie Eradication Uniform Methods and Rules) prior to it becoming
enacted by APHIS. That is the good
news, the bad news is that there has been a lack of awareness of the potential
impact of a scrapie program by producers. Many
seed-stock producers assume they will not be impacted by the new rule and thus
will be able to continue on with business as usual after the new rule becomes a
reality. This thinking will likely
catch many unprepared and in a scurry to get on the program in order to access
previous markets. The following is
a list of what you might expect to see in the new program.
Every state that wants to be able to move sheep and goats
interstate with minimal restrictions must have a Scrapie program that meets at
least the minimum requirements of
the Federal Program. The federal
program requires producers of both sheep and goats to identify all breeding
animals moving interstate and all sheep over 18 months of age.
States must expand this to identification of these animals on change of
ownership within 2 years of the rule being finalized.
Producers are not required to enroll in a program to move their animals
interstate unless their State does not meet the minimum federal requirements.
All 50 states have agreed to meet these requirements and are currently
meeting the requirements for investigating and restricting the movement of
infected and source flocks. Every producer of sheep and goats, who wishes to transport
animals across state lines, will be required to be enrolled in the Scrapie
program. This will then require
that every animal will have individual identification, unless the animals are
going directly to slaughter, then there will likely be another process wherein
those animals will be identified at the slaughter plant. The following is a summary of what is in the two proposed
rules and the UM&R by APHIS: The proposed rule, Scrapie in Sheep and Goats: Interstate
Movement Restriction and Indemnity Program, with the changes indicated in the
Consistent State Proposal, would require that breeding sheep and goats and sheep
over 18 months of age in interstate commerce be identified.
No one is required to join the VSFCP in order to move sheep or goats
unless they are in a State that has not agreed to be a consistent State, since
all 50 States have agreed to be consistent no one will have to join the VSFCP to
move animals. The purpose of sheep and goat identification is to
be able to trace scrapie infected and exposed animals. The identification methods that will be required will not be
finalized until the interstate movement rule is finalized.
At that time APHIS will start an intense effort to inform producers,
marketers, dealers, and slaughter establishments about any new identification
requirements for interstate movement that will be required. The proposed rule allows for the use of either premise
based individual animal identification, individual animal identification, or in
limited circumstances premise-based identification to identify animals in
interstate movement. This would
mean that either standard USDA alphanumeric metal eartags, or, in the case of
animals moving direct to slaughter, backtags could be used by accredited
veterinarians, markets dealers , or producers as long as the tag numbers have
been assigned by a State or APHIS representative and recorded in the scrapie
database. These eartags will be
made available to producers before the effective date of the rule.
Alternatively, producers who prefer not to use USDA tags may either
purchase eartags that are imprinted with an assigned premise identification
number that either contains or is used in association with a unique production
number from an approved tag company; or apply a legible tattoo that contains the
assigned premise number and an individual production number.
APHIS will approve tag companies to make eartags and backtags for this
purpose. We anticipate that premise
eartags will range in cost of $.06 for metal tags to $1.00 for tamper resistant
flap tags. Owners of registered
animals will be able to use legible registration tattoos.
In those limited situations where premise identification is permitted
brands registered with an official brand registry would be allowed.
Participants in the Voluntary Scrapie Flock Certification Program will be
able to continue to use the identification methods currently allowed by the
program to identify their animals for interstate movement.
Perhaps a better way to view the new program is to look at
it from a proactive view rather than the reactive view.
It is my recommendation that every sheep and goat seed stock producer in
the United States contact their Federal Veterinarian and request an enrollment
packet. The enrollment process
begins by following the instructions, which come with the packet; most often
they will be as follows:
The program has some real positive points that can really assist the sheep and goat industries. First, the recent ‘Starlink’ corn issue has reinforced in my mind the demand of the American consumer that their food be absolutely safe and healthy. The current epidemic of Hoof and Mouth disease in England is additional proof that we could be out of business tomorrow as an industry unless we take positive steps to deal with our future. Further, the concept of trace-back is here and since goats and white sheep have had very few cases of scrapie in the past, it should be re relatively easy process for us to get on the program and soon be able to certify to consumers that the meat is certified free from scrapie and a totally safe food source. Another significant benefit will come in foreign sales. Since New Zealand and Australia are free from the disease, they currently have markets locked up which we cannot access because of scrapie such as China and India. Our ability to access markets in China is alone sufficient incentive to get on the program and certify not only our individual flocks, but also the entire country free from this mystery disease. In conclusion, I recommend that every producer contact their Federal Veterinarian and get enrolled as soon as possible. It will not only assist in beating the rush when it is required, but it will also get you started towards a certified scrapie free flock. If you have comments or questions please feel free to email me at ewenique@allwest.net. |
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