Scrapies Research Paper
Scrapies
Scrapies is a fatal neurodegenerative disease that affects the central nervous system of sheep and goats. It is classified a transmissible spongiform encephalopathy also known as a TSE. Scrapies is the oldest known TSE. There is no cure or treatment for scrapies meaning it is a terminal disease. The name scrapies came from the symptom that leads constant itching due to the damage in the brain. The constant itching results in scabs and scrapes all over the body. The number one theory of the cause of scrapies is prions. Prions are tiny abnormal proteins that are similar to a virus and contains no genetic components. Other theories suggest that scrapies is a virus that has uncommon characteristics or it is a virino. A virino is an extremely small piece of DNA that acts like a virus. The scrapie agent is extremely resistant to heat and typical sterilization processes and does not provoke any inflammation or immune system responses. Flocks and herds infected with the disease are unviable. This …show more content…
makes it unsafe for the United States of America to export breeding stock, embryos, and semen to other countries.
Goat infected with scrapies. Sheep infected with scrapie.
Transmissible Spongiform Encephalopathies
TSE
Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, are a group of progressive conditions that affect the brain (encephalopathies) and nervous system of many animals, including humans. TSEs are rare degenerative brain disease that leaves the brain with a “spongy” appearance. The holes in the brain can be seen when looking at the tissue under a microscope. An example of a human Transmissible Spongiform Encephalopathies is Creutzfeldt-Jakob disease also known as CJD and is the most well-known of the human TSE. One other example is bovine spongiform encephalopathy (BSE) or mad cow disease. Scrapies is different than other TSE because genetics play a role into the susceptibility and resistance to the disease. There is a theory that the occurrence of TSEs in captive wild animals is a result of BSE-contaminated feed. Brain tissue sample with Scrapies.
History
Scrapies was first recognized as a disease in Great Britain and other countries of Western Europe like France and Germany more than 250 years ago. In French the name is ‘La tremblante’ because of the shaking of the animal’s body because of the brain damage. The disease has now been reported throughout the world, but there are 2 countries that are recognized by the United States of America as scrapies free, and those are Australia and New Zealand. The first case in the USA was in a Michigan flock. The owner of the flock had imported sheep of British origin through Canada. On November 2014 the first goat in the United States tested positive for scrapies. In 1966 Alper demonstrated that the TSE agent was very UV-resistant making people question that it was a virus. PrP, the prion protein, was first found in 1968. The prion protein was identified by a man named Dickinson. He discovered this by incubating scrapies in mice.
Old fashioned map of Europe.
Symptoms
Symptoms tend to vary and develop slowly because of the nerve cell damage. The most common symptoms tend to be behavioral change tremor more noticeable in the head and neck, Prius and locomotor incoordination, and convulse collapse. Early signs include subtle changes in behavior or temperament, loss of coordination, constant itching and rubbing on fixed items, Wight loss, biting at limbs, lip smacking, hopping, swaying of the backend, and high-stepping of the forelegs. They are more prone to common illnesses and parasites like lice and worms. The signs or effects of the disease usually appear 2-5 years after the animal is infected but the time of effects tend to vary. The host may live 1 to 6 months or longer after the onset of clinical signs but death is inevitable. Scrape on a goats barrel from itching.
Transmission
The most common way for a host to contract scrapies is through its mother. The placenta and placental fluids are common ways for goats and sheep to get scrapies. Theories suggest that prions are spread through urine and saliva and can stay in the environment for decades. The prions have also been said to be found in soil and when goats or sheep graze and eat grass they can ingest prions. If the goat or sheep has had a blood transfusion there is a chance that is how it contracted scrapies. There is no epidemiologic evidence that scrapies is transmitted to humans such as through contact on farms, the butchers, or through consumption. A goat placenta. A goat after kidding.
Diagnosis
Veterinarians diagnose scrapies based on the appearance of the animal with the combination of the knowledge of the animal’s history. Scrapies can currently be confirmed by microscopic examination of the brain tissue or by procedures that detect the presence of abnormal prions protein. The test that determines if there is abnormal prions present is a ELISA also known as an enzyme-linked immunosorbent assay, a western-blot, or preforming immunohistochemistry on any tissue samples. A positive test result must be confirmed by the National Veterinary Services Laboratories or a lab that has permission to conduct scrapies testing. To test a live animal you can take a tissue sample from the 3rd eyelid that moistens and protects the eye or tonsils, tissue samples other than the brain are not very accurate because scrapies host usually doesn't have prions present outside of the brain. The only accurate diagnostic test currently available to determine if a sheep or goat has scrapies require brain or lymphoid tissue. You can collect brain tissue by removing and submitting the whole head or you can call an official to come and collect specific tissue. Ovine progressive pneumonia and rabies show similar symptoms sometimes leading to confusion during diagnosis. See figure 1 for number of animals sampled for scrapies testing by Quarter in 2016.
If you plan on testing or shipping any tissue samples you can contact: Shipping Address phone and E-mail Address
Veterinary Services phone: (317)-347-3100 Remington Facility Fax: (219)-216-2357 18795 S 580W E-mail: Remington.Locker@aphis.usda.gov
Remington, IN 47977
Prevention
Precautions you can take to protect your flock or herd is close your flock to female additions because scrapies is transmitted primarily by females during birth, and in sheep, you can invest in a genetic resistance ram which leads to higher resistance or less susceptible in their offspring. They have not identified a gene in goats that leads to genetic resistance and a genetic test cannot tell you if the sheep is infected with scrapies. You can also make sure you clean up after birthing and test for scrapies and test any new additions to your flock or heard.
Tips for cleaning up after birthing is to remove the placenta, replace all bedding, and after the mother and the kids are done in the breeding pen be sure to disinfect the whole area.
Eradication program
The United States department of agriculture or also referred to as the USDA has indicated an accelerated scrapies eradication program. The eradication program is also called the National Scrapie Eradication Program and for short the NSEP. The program was started in 2001 and has reduced the number of scrapies cases by over 85%. The USDA runs it with the help of the state government, federal government, and the sheep and goat industry. NSEP’s steps to eradicate scrapies is to quarantine or destroy the infected animal. They do this by destroying high risk or infected animals, live animal testing and genetic testing, and testing exposed animals. Producers can help the eradication of scrapies by doing the following, Identification of preclinical host and following your state regulations, tracing of infected goats and sheep, reporting suspected animals to a state, federal or accredited veterinarian, participating in effective cleanup of infected herd or flocks, and submitting heads from sheep and goats over 18 months that died for scrapie testing. As of many as 31, 2016 26,258 animals have tested. 20,721 were sheep and 5,537 of them were goats. Just in Idaho, 580 sheep tested and 98 goats tested (See Figure 2).
The Idaho state regulations are, “All sheep and goats except exempt animals must carry an official ear tag or be. The Exemptions are neutered animals under 18 months of age; breeding animals under 18 months of age shipped directly to an approved slaughter establishment or shipped directly to a feedlot for finish feeding for slaughter only; castrated or low-risk commercial goats; and registered sheep and goats accompanied by registration papers or a certificate of veterinary inspection with registrations tattoos. Goats registered with a National Goat Registry that allows for electronic implant identification, as recorded on a registration certificate, may be identified with an electronic implant.” (www.eradicatescrapies.org)
Eradication Program continued
Complete information is available by contacting:
Dr.
Bill Barton, SV Dr. Mary K. Tinker
Ph.: 208-332-8540 Ph.: 208-378-5631
E-mail: bill.barton@isda.idaho.gov E-mail: mary.k.tinker@aphis.usda.gov
USDA/APHIS/VS Office USDA/APHID/VS Offices
If you need tags you can call 1-866-USDA-TAG
Boer with ear tags. An ear after tattooing.
Tagging and Tattooing
Tagging or tattooing does is requirement and is very important for all goat and sheep owners to know. Below are the steps to tagging and tattooing.
Tagging steps
What you will need:
Ear tag applicator
Ear tags
Ear tag pen
Rubbing alcohol
Step one: Squeeze the handles of the tag applicator to check that the pin slides easily into the hole on the opposite end. This is to ensure that the halves of the tag will meet
properly.
Step two: Restrain your goat by holding it, straddling, or holding their head to you thigh, Make sure you have free access to the ear to be tagged.
Step three: Identify the area on the ear that you want tagged. Make sure not to tag on the large veins in your goat's ears. The veins are located in the large creases in the ear.
Step four: Clean area with rubbing alcohol where the tag will be inserted.
Step five: Position the ear tagger and give it strong squeeze. Ear tagging causes about as much pain as getting your own ears pierced.
Step six: Watch the animal over the next few week for signs of infection or tissue death. If there is redness, sever pain, or discharge remove the tag and talk to you veterinarian.
Tagging and Tattooing Continued
Steps to Tattooing
What you will need:
Gloves
Halter or leash
Rubbing alcohol
Clean cloth
Tattoo ink
Tattoo kit
Step one: clean the ear entirely with the rubbing alcohol to prevent infection. If you goat or sheep has very hairy ears it may be helpful to trim them.
Step Two: Apply a generous amount of ink to the ears. Green ink is the recommended color but other colors are ok.
Step three: Punch a piece of paper with the information you plan to tattoo with to assure that all of the information is correct and all of you equipment is working correctly too.
Step four: Hold the animal securely. You can use any of the techniques said above for tagging.
Step five: place the tongs in the center of the ear between the ribs of cartilage and squeeze firmly. Avoiding the ribs will prevent bleeding. Be sure to lift the tongs out straight to prevent scratching because scratches can ruin the tattoo.
Step six: watch the animal and make sure there are no complications
Current Research
The research going on right now is to developing more practical live animals testing to diagnose infect animals before they show signs, investing transmissibility of the agent, identifying the scrapie agent and its different strains, identifying genes that influence scrapies infection and evaluating genetic selection a tools. Addition experimental data to support existing evidence is needed. As of June 30, 2016 there have been 41 scrapies cases in goats from 2002-2016 (see Figure 3). In 2016 13 sheep have tested positive in the following states: Indiana, Michigan, Ohio, and Texas (see figure 4).
Scrapies is a fatal neurodegenerative disease that affects the central nervous system of sheep and goats. It is classified a transmissible spongiform encephalopathy also known as a TSE. Scrapies is the oldest known TSE. There is no cure or treatment for scrapies meaning it is a terminal disease. The name scrapies came from the symptom that leads constant itching due to the damage in the brain. The constant itching results in scabs and scrapes all over the body. The number one theory of the cause of scrapies is prions. Prions are tiny abnormal proteins that are similar to a virus and contains no genetic components. Other theories suggest that scrapies is a virus that has uncommon characteristics or it is a virino. A virino is an extremely small piece of DNA that acts like a virus. The scrapie agent is extremely resistant to heat and typical sterilization processes and does not provoke any inflammation or immune system responses. Flocks and herds infected with the disease are unviable. This …show more content…
makes it unsafe for the United States of America to export breeding stock, embryos, and semen to other countries.
Goat infected with scrapies. Sheep infected with scrapie.
Transmissible Spongiform Encephalopathies
TSE
Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, are a group of progressive conditions that affect the brain (encephalopathies) and nervous system of many animals, including humans. TSEs are rare degenerative brain disease that leaves the brain with a “spongy” appearance. The holes in the brain can be seen when looking at the tissue under a microscope. An example of a human Transmissible Spongiform Encephalopathies is Creutzfeldt-Jakob disease also known as CJD and is the most well-known of the human TSE. One other example is bovine spongiform encephalopathy (BSE) or mad cow disease. Scrapies is different than other TSE because genetics play a role into the susceptibility and resistance to the disease. There is a theory that the occurrence of TSEs in captive wild animals is a result of BSE-contaminated feed. Brain tissue sample with Scrapies.
History
Scrapies was first recognized as a disease in Great Britain and other countries of Western Europe like France and Germany more than 250 years ago. In French the name is ‘La tremblante’ because of the shaking of the animal’s body because of the brain damage. The disease has now been reported throughout the world, but there are 2 countries that are recognized by the United States of America as scrapies free, and those are Australia and New Zealand. The first case in the USA was in a Michigan flock. The owner of the flock had imported sheep of British origin through Canada. On November 2014 the first goat in the United States tested positive for scrapies. In 1966 Alper demonstrated that the TSE agent was very UV-resistant making people question that it was a virus. PrP, the prion protein, was first found in 1968. The prion protein was identified by a man named Dickinson. He discovered this by incubating scrapies in mice.
Old fashioned map of Europe.
Symptoms
Symptoms tend to vary and develop slowly because of the nerve cell damage. The most common symptoms tend to be behavioral change tremor more noticeable in the head and neck, Prius and locomotor incoordination, and convulse collapse. Early signs include subtle changes in behavior or temperament, loss of coordination, constant itching and rubbing on fixed items, Wight loss, biting at limbs, lip smacking, hopping, swaying of the backend, and high-stepping of the forelegs. They are more prone to common illnesses and parasites like lice and worms. The signs or effects of the disease usually appear 2-5 years after the animal is infected but the time of effects tend to vary. The host may live 1 to 6 months or longer after the onset of clinical signs but death is inevitable. Scrape on a goats barrel from itching.
Transmission
The most common way for a host to contract scrapies is through its mother. The placenta and placental fluids are common ways for goats and sheep to get scrapies. Theories suggest that prions are spread through urine and saliva and can stay in the environment for decades. The prions have also been said to be found in soil and when goats or sheep graze and eat grass they can ingest prions. If the goat or sheep has had a blood transfusion there is a chance that is how it contracted scrapies. There is no epidemiologic evidence that scrapies is transmitted to humans such as through contact on farms, the butchers, or through consumption. A goat placenta. A goat after kidding.
Diagnosis
Veterinarians diagnose scrapies based on the appearance of the animal with the combination of the knowledge of the animal’s history. Scrapies can currently be confirmed by microscopic examination of the brain tissue or by procedures that detect the presence of abnormal prions protein. The test that determines if there is abnormal prions present is a ELISA also known as an enzyme-linked immunosorbent assay, a western-blot, or preforming immunohistochemistry on any tissue samples. A positive test result must be confirmed by the National Veterinary Services Laboratories or a lab that has permission to conduct scrapies testing. To test a live animal you can take a tissue sample from the 3rd eyelid that moistens and protects the eye or tonsils, tissue samples other than the brain are not very accurate because scrapies host usually doesn't have prions present outside of the brain. The only accurate diagnostic test currently available to determine if a sheep or goat has scrapies require brain or lymphoid tissue. You can collect brain tissue by removing and submitting the whole head or you can call an official to come and collect specific tissue. Ovine progressive pneumonia and rabies show similar symptoms sometimes leading to confusion during diagnosis. See figure 1 for number of animals sampled for scrapies testing by Quarter in 2016.
If you plan on testing or shipping any tissue samples you can contact: Shipping Address phone and E-mail Address
Veterinary Services phone: (317)-347-3100 Remington Facility Fax: (219)-216-2357 18795 S 580W E-mail: Remington.Locker@aphis.usda.gov
Remington, IN 47977
Prevention
Precautions you can take to protect your flock or herd is close your flock to female additions because scrapies is transmitted primarily by females during birth, and in sheep, you can invest in a genetic resistance ram which leads to higher resistance or less susceptible in their offspring. They have not identified a gene in goats that leads to genetic resistance and a genetic test cannot tell you if the sheep is infected with scrapies. You can also make sure you clean up after birthing and test for scrapies and test any new additions to your flock or heard.
Tips for cleaning up after birthing is to remove the placenta, replace all bedding, and after the mother and the kids are done in the breeding pen be sure to disinfect the whole area.
Eradication program
The United States department of agriculture or also referred to as the USDA has indicated an accelerated scrapies eradication program. The eradication program is also called the National Scrapie Eradication Program and for short the NSEP. The program was started in 2001 and has reduced the number of scrapies cases by over 85%. The USDA runs it with the help of the state government, federal government, and the sheep and goat industry. NSEP’s steps to eradicate scrapies is to quarantine or destroy the infected animal. They do this by destroying high risk or infected animals, live animal testing and genetic testing, and testing exposed animals. Producers can help the eradication of scrapies by doing the following, Identification of preclinical host and following your state regulations, tracing of infected goats and sheep, reporting suspected animals to a state, federal or accredited veterinarian, participating in effective cleanup of infected herd or flocks, and submitting heads from sheep and goats over 18 months that died for scrapie testing. As of many as 31, 2016 26,258 animals have tested. 20,721 were sheep and 5,537 of them were goats. Just in Idaho, 580 sheep tested and 98 goats tested (See Figure 2).
The Idaho state regulations are, “All sheep and goats except exempt animals must carry an official ear tag or be. The Exemptions are neutered animals under 18 months of age; breeding animals under 18 months of age shipped directly to an approved slaughter establishment or shipped directly to a feedlot for finish feeding for slaughter only; castrated or low-risk commercial goats; and registered sheep and goats accompanied by registration papers or a certificate of veterinary inspection with registrations tattoos. Goats registered with a National Goat Registry that allows for electronic implant identification, as recorded on a registration certificate, may be identified with an electronic implant.” (www.eradicatescrapies.org)
Eradication Program continued
Complete information is available by contacting:
Dr.
Bill Barton, SV Dr. Mary K. Tinker
Ph.: 208-332-8540 Ph.: 208-378-5631
E-mail: bill.barton@isda.idaho.gov E-mail: mary.k.tinker@aphis.usda.gov
USDA/APHIS/VS Office USDA/APHID/VS Offices
If you need tags you can call 1-866-USDA-TAG
Boer with ear tags. An ear after tattooing.
Tagging and Tattooing
Tagging or tattooing does is requirement and is very important for all goat and sheep owners to know. Below are the steps to tagging and tattooing.
Tagging steps
What you will need:
Ear tag applicator
Ear tags
Ear tag pen
Rubbing alcohol
Step one: Squeeze the handles of the tag applicator to check that the pin slides easily into the hole on the opposite end. This is to ensure that the halves of the tag will meet
properly.
Step two: Restrain your goat by holding it, straddling, or holding their head to you thigh, Make sure you have free access to the ear to be tagged.
Step three: Identify the area on the ear that you want tagged. Make sure not to tag on the large veins in your goat's ears. The veins are located in the large creases in the ear.
Step four: Clean area with rubbing alcohol where the tag will be inserted.
Step five: Position the ear tagger and give it strong squeeze. Ear tagging causes about as much pain as getting your own ears pierced.
Step six: Watch the animal over the next few week for signs of infection or tissue death. If there is redness, sever pain, or discharge remove the tag and talk to you veterinarian.
Tagging and Tattooing Continued
Steps to Tattooing
What you will need:
Gloves
Halter or leash
Rubbing alcohol
Clean cloth
Tattoo ink
Tattoo kit
Step one: clean the ear entirely with the rubbing alcohol to prevent infection. If you goat or sheep has very hairy ears it may be helpful to trim them.
Step Two: Apply a generous amount of ink to the ears. Green ink is the recommended color but other colors are ok.
Step three: Punch a piece of paper with the information you plan to tattoo with to assure that all of the information is correct and all of you equipment is working correctly too.
Step four: Hold the animal securely. You can use any of the techniques said above for tagging.
Step five: place the tongs in the center of the ear between the ribs of cartilage and squeeze firmly. Avoiding the ribs will prevent bleeding. Be sure to lift the tongs out straight to prevent scratching because scratches can ruin the tattoo.
Step six: watch the animal and make sure there are no complications
Current Research
The research going on right now is to developing more practical live animals testing to diagnose infect animals before they show signs, investing transmissibility of the agent, identifying the scrapie agent and its different strains, identifying genes that influence scrapies infection and evaluating genetic selection a tools. Addition experimental data to support existing evidence is needed. As of June 30, 2016 there have been 41 scrapies cases in goats from 2002-2016 (see Figure 3). In 2016 13 sheep have tested positive in the following states: Indiana, Michigan, Ohio, and Texas (see figure 4).