The Possible Mechanisms of Scrapie Contraction
Scrapie was first discovered in Great Britain in the late 1900’s. The first case of scrapie in the United States was found in Michigan in 1947 when the flock owner had imported sheep of British origin several years prior. Since then scientists have researched to find the cause of the scrapie agent that are classified as transmissible spongiform encephalopathy. At the present, scientists have presented three main theories that explain why the scrapie agent holds a dangerous threat against its host and how it elicits its symptoms. Scientists are finding genetic alternatives to prevent and dampen the spread of scrapie within sheep and goat flocks. They use methods such as tatoing and genetic selection to regulate animals exposure to the pathogen.
Scrapie is defined as a fatal, degenerative disease affecting the central nervous system of sheep and goats. It is widely feared because of its uncertain origin and therefore its seemingly incurable status. It is closely related and often associated with bovine spongiform encephalopathy (BSE; also known as “Mad Cow” disease), as well Chronic Wasting Disease (found in deer and elk) all of which are classified as transmissible spongiform encephalopathy. (Q&A. July 2005 http://www.animalagriculture.org/scrapie/AboutScrapie/QandA.htm)
Scrapie is usually transmitted from the mother to her baby sheep or goats, through the placenta or the placental fluids. Animals infected with scrapie experience the symptoms and effects of the disease after two to five years post infection. Scrapie can be transmitted to susceptible sheep and goats through contact with the placenta and placental fluids of infected animals. There has been no evidence of human trans...
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...entists alike are trying to make up new procedures of prevention to dampen the further spread of scrapie throughout the population of sheep and goats.
Such measures taken to prevent the spread of scrapie include the genetic-based flock clean up plan. Here, genetic selection is used as the primary means of scrapie regulation. The United State s Department of Agriculture’s Animal Plant Health Inspection Service is using genetic testing to determine which exposed animals must be removed or restricted in affected
flocks and which are free to move unrestricted. This genetic clean up plan calls for the removal or restriction of all exposed susceptible sheep and goats as well as a five-year cycle of strict monitoring for the breeding of all the livestock (The Genetics of Scrapie Susceptibility. July 26 2005: http://www.aphis.usda/gov/us/nahps/scrapie/scrapie_genetics.pdf).
Every year worldwide, over seventy billion animals are killed for food in factories without the inclusion aquatic animals (“Factory Farms Overview¨). The animal rights movement began in Europe during the nineteenth century to protect horses, dogs and cats (Recarte 1). However, now modern animal rights groups have switched their focus to factory farms, test animals and the removal of ag-gag laws. The fight to create less painful and stressful environments in factories and the altogether removal of animal testing and ag-gag laws has been taken on by animal rights groups like ASPCA (“Factory Farms”). The biggest issue currently facing animals is factory farming.
This is not the first time or even the first animal to have become a problem. Other problem animals such as the feral hogs, Norwegian rats and the German cockroach’s’ are examples of what happens when a problem goes untreated or under treated. In 2011, the Department of the Interi...
Like most nonnative, invasive species, feral swine (Sus scrofa) in the United States has an increasingly negative impact on native plants. If left unchecked, feral swine will become responsible for the permanent destruction of many plant communities as well as endangering native plant populations.
Chronic Wasting Disease (CWD) is a fatal neuro-degenerative, transmissible spongiform encephalopathy (TSE) of the family Cervidae (Hamir, et.al., 2006). The family Cervidae includes mule deer, Odocolileus hemionus, white-tailed deer, Odocolileus virginianus, Rocky Mountain elk, Cervus elaphus nelsoni, and moose, Alces alces shirasi, among others (Sigurdon & Aguzzi, 2007). CWD is a prion disease, meaning it is a protein caused infection, that occurs naturally in the deer family (Song & Lawson, 2009). This protein is suspected to be an abnormal isoform (PrPSc) of the naturally occurring host prion protein (PrPC) (Blanchong, et. Al., 2009). Bovine spongiform encephalopathy (BSE), mad cow disease, is a similar prion effecting cattle as CWD affects Cervidae. Although, scientists are not sure of transmission route it is suspected that CWD is transmissible and infectious through direct contact with infected individuals or through environmental contamination (Song & Lawson, 2009). Tests have been performed showing susceptibility of altered mice to oral transmission, mimicking the suspected route of entry, and the incubation appears slower but lasts longer with oral infection (Trifilo, et.al., 2007). The approximate time from the initial infection to death is three years.
TSEs or more commonly prion diseases are a group of invariably fatal neurodegenerative diseases that occur in humans and animals . This disease is caused by a protease –resistant protein (PrPsc) after misfolding of a host-encoded prion protein (PrP). TSEs can exist as genetic, infectious or sporadic forms. The diseases are characterized by dementia, ataxia and neuropathlogically due to loss of specific neurons in the brain. Other clinical features include persistent painful stimuli, dystonia, visual or cerebellar problems and gliosis (1).
... eggs in the United States. As evidence indicates, the greatest impact of Proposition Two will be felt by the California egg industry6. Proposition Two is also risk to the safety of farm animal, the products they produce, and decreases sanitation practices in comparison to modern housing. Under the conditions of Proposition Two, livestock would be at a higher risk of contracting communicable diseases in comparison to the disease/infection risks posed by current caging methods. Proposition Voting no on Proposition Two will keep the animal agriculture business and its animals safe and healthy while keeping the California egg industry secure. Proposition Two appears to be a measure with great potential for both the animal welfare and animal agriculture, but in reality, studies and research have concluded that Proposition Two is a detriment to both animals and humans.
the animals and cattle as well. The disease was so contagious that touching even an object that had
Prairie dogs are well known for being a “plague-ridden, land-destroying blight.” In “Denver’s Street-Smart Prairie Dogs,” Morgan Heim states, “... their tendency to chew down grass and create dusty, pock-marked landscapes in pastures, cropland and backyards.” This argues that prairie dogs disrupted ways are destroying our lands, and in order to protect our lands we need to exterminate them. Furthermore to this evidence, the text, “Prairie Dogs: A Threatened Species or Public Nuisance?” it also claims,
Norcross, Alastair. “Puppies, Pigs, and People: Eating Meat and Marginal Cases.” Philosophical Perspectives 18, (2004): 229-245.
United States. House of Representatives. Committee on Agriculture. “Puppy Uniform Protection and Safety Act.” Thomas Library of Congress. Government Publication Office. 27 Feb. 2013. Web. 14 Nov. 2013
However, health concerned organizations want to ban the use of these products due to the increasing fears that they can cause harm to the consumers. For over 50 years, antibiotics have been added to the food of animals such as poultry, cattle and pigs. The main purpose for doing so is to lower the risk of disease in animals. Farm animals are housed together in overcrowded areas, which are very dirty. The hygiene level can get to such a poor state that they are often in contact with their own excreta as well as excreta of the other animals they are housed with and because of tight single air space they share, the likelihood of catching diseases from one another is further increased and very often a whole heard can be infected at one time.
Researchers from the Animal Parasitic Laboratory and Agriculture Research Service of the United States Department of Agriculture concluded that the linage of Trichinella spiralis originated from Europe over several thousand years ago (Rosenthal, LaRosa, Zarlenga, Dumans, Chunyu, Mingyuan & Pozio, 2008). This is the approximate time when pigs were first domesticated in that region. This implies that the species Trichinella spiralis was introduced to the Americas from pigs. However, there is evidence that the early people of this world, hominid hunters, have consumed foodborne parasites by hunting wild game from millions of years before. Today, swine is governed on the ensuing transmission, and evolutionary diversification.
When hygienic conditions were poor polio attacked infants. The disease was spread by contaminated water and contact with fecal contamination. Many infants died when the conditions were poor. But as conditions improved the virus spread differently. It was spread more through playmates and family members, the contamination came from the nose and throat. By the early 1950s, twenty-five percent of paralytic cases occurred in people 21 years old or older.
Puppies from puppy mills are prone to congenital and hereditary conditions such as heart disease and kidney disease.
Protect biodiversity by opposing the privatisation and manipulation of the plant and animal gene pool.