Mad Cow Disease

'Mad Cow Disease' in Cattle Can Spread Widely in Autonomic Nervous System Before Detectable in the Central Nervous System

ScienceDaily (July 9, 2012) — Bovine spongiform encephalopathy (BSE, or "mad cow disease") is a fatal disease in cattle that causes portions of the brain to turn sponge-like. This transmissible disease is caused by the propagation of a misfolded form of protein known as a prion, rather than by a bacterium or virus. The average time from infection to signs of illness is about 60 months. Little is known about the pathogenesis of BSE in the early incubation period. Previous research has reported that the autonomic nervous system (ANS) becomes affected by the disease only after the central nervous system (CNS) has been infected.

In a new study published online in the August issue of The American Journal of Pathology, researchers found that the ANS can show signs of infection prior to involvement of the CNS.

"Our results clearly indicate that both pathways are involved in the early pathogenesis of BSE, but not necessarily simultaneously," reports lead investigator Martin H. Groschup, PhD, Institute for Novel and Emerging Infectious Diseases at the Friedrich-Loeffler-Institut, Riems, Germany.

To understand the pathogenesis of BSE, fifty-six calves between four and six months of age were infected orally with BSE from infected cattle. Eighteen calves were inoculated orally with BSE-negative material from calf brainstem as controls. The study also included samples collected from a calf that had died naturally of BSE. Tissue samples from the gut, the CNS, and the ANS were collected from animals every four months from 16 to 44 months after infection. The samples were examined for the presence of prions by immunohistochemistry. Samples were also used to infect experimental mice that are highly sensitive to a BSE infection.

A distinct accumulation of the pathological prion protein was observed in the gut in almost all samples. BSE prions were found in the sympathetic ANS system, located in the thoracic and lumbar spinal cord, starting at 16 months after infection; and in the parasympathetic ANS, located in the sacral region of the spinal cord and the medulla, from 20 months post infection. There was little or no sign of infection in the CNS in these samples. The sympathetic part of the ANS was more widely involved in the early pathogenesis than its parasympathetic counterpart. More bovines showing clinical symptoms revealed signs of infection in the sympathetic nervous system structures at a higher degree than in the parasympathetic tissue samples. The earliest detection of BSE prions in the brainstem was at 24 months post infection. However, infection detected in the spinal cord of one animal at 16 months post infection suggests the existence of an additional pathway to the brain.

"The clear involvement of the sympathetic nervous system illustrates that it plays an important role in the pathogenesis of BSE in cattle," notes Dr. Groschup. "Nevertheless, our results also support earlier research that postulated an early parasympathetic route for BSE."

The results, Dr. Groschup says, indicate three possible neuronal routes for the ascension of BSE prions to the brain: sympathetic, parasympathetic, and spinal cord projections, in order of importance. "Our study sheds light on the pathogenesis of BSE in cattle during the early incubation period, with implications for diagnostic strategies and food-safety measures."

Story Source:

The above story is reprinted from materials provided byElsevier.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

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Journal Reference:

1. Martin Kaatz, Christine Fast, Ute Ziegler, Anne Balkema-Buschmann, Bärbel Hammerschmidt, Markus Keller, Anja Oelschlegel, Leila McIntyre, Martin H. Groschup. Spread of Classic BSE Prions from the Gut via the Peripheral Nervous System to the Brain. The American Journal of Pathology, 2012; DOI: 10.1016/j.ajpath.2012.05.001

link: http://www.sciencedaily.com/releases/2012/07/120709093117.htm

Motion Sensors for Horse Lameness

Motion Sensors Detect Horse Lameness Earlier Than Veterinarians

ScienceDaily (July 3, 2012) — The most common ailment to affect a horse is lameness. A University of Missouri equine veterinarian has developed a way to detect this problem using a motion detection system called the "Lameness Locator." Now, Kevin Keegan, a professor of equine surgery in the College of Veterinary Medicine at MU, has found that his Lameness Locator can detect lameness earlier than veterinarians using the traditional method of a subjective eye test.

Equine veterinarians have developed a way to detect lameness using a motion detection system called the "Lameness Locator." (Credit: Image courtesy of University of Missouri-Columbia)

The Lameness Locator, which is now in commercial use, places small sensors on the horse's head, right front limb and croup, near the tail. The sensors monitor and record the horse's torso movement while the horse is trotting. The recorded information is then transferred to a computer or mobile device and compared against databases recorded from the movement of healthy horses and other lame horses. The computer is then able to diagnose whether or not the horse is lame.

In a new study published in theEquine Veterinary Journal, Keegan and co-author Meghan McCracken, an equine surgery resident at MU, put special adjustable shoes on horses that temporarily induced symptoms of lameness. The horses were then monitored by the Lameness Locator as well as by a number of veterinarians using any lameness testing methods they wished. If no lameness was detected by either the veterinarians or the Lameness Locator, the special shoes were adjusted slightly to increase the symptoms of lameness. This process was repeated until both the Lameness Locator and the participating veterinarians properly identified in which leg of the horse the lameness was occurring. Keegan and McCracken found that the Lameness Locator was able to correctly identify lameness earlier than veterinarians using subjective eye test methods more than 58 percent of the time and more than 67 percent of the time when the lameness occurred in the hind legs of the horse. Keegan attributes this to the sensors' high sensitivity levels.

"There are two reasons why the Lameness Locator is better than the naked eye," Keegan said. "It samples motion at a higher frequency beyond the capability of the human eye and it removes the bias that frequently accompanies human subjective evaluation."

Because equine lameness may begin subtly and can range from a simple mild problem affecting a single limb to a more complicated one affecting multiple limbs, veterinarians and horse owners know that early detection is the key to successful outcomes.

"If veterinarians can detect lameness earlier, before it gets too bad, it makes treatment much easier," Keegan said. "Lameness often goes undetected or undiagnosed entirely, which can cause owners to retire horses earlier than needed, simply because they cannot figure out why the horses are unhealthy. The Lameness Locator should be able to help with that as well."

Story Source:

The above story is reprinted from materials provided byUniversity of Missouri-Columbia.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.

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Journal Reference:

1. M. J. Mccracken, J. Kramer, K. G. Keegan, M. Lopes, D. A. Wilson, S. K. Reed, A. Lacarrubba, M. Rasch.Comparison of an inertial sensor system of lameness quantification with subjective lameness evaluation.Equine Veterinary Journal, 2012; DOI: 10.1111/j.2042-3306.2012.00571.x

http://www.sciencedaily.com/releases/2012/07/120703162620.htm

Animal microchips

Animal microchips linked to causing cancer

(NaturalNews) Many veterinarians recommend them, and most animal shelters require them. Identification microchips injected into the necks of cats and dogs are touted as useful in recovering lost pets because the devices store owner and medical information. But are they safe? A new lawsuit against Merck & Co., Inc., maker of the HomeAgain pet microchip, says they are not, noting that they can cause cancer to develop in pets.



Featured at www.ChipMeNot.org, a website launched to raise awareness about the harm caused to animals by microchips, the lawsuit alleges that Merck's HomeAgain pet microchip induces cancerous tumors in pets. According to the suit, the defendant's cat developed cancer after getting a chip implant, and according to reports, other animals have gotten cancer after getting chipped as well.

"Based on the alarming number of microchip-induced cancers we're discovering, I predict this lawsuit will be just the tip of the iceberg," said Dr. Katherine Albrecht, a consumer advocate and expert on side effects associated with implantable microchips. "Merck and organizations that advocate pet chipping should take this lawsuit seriously and start warning pet owners of the risk of microchip-induced cancer."

According to the U.S. Food and Drug Administration, potential health risks associated with implantable microchips include "adverse tissue reaction". Based on data from the British Small Animal Veterinary Association, this can include "swelling", "infection", "abscesses", and "tumors".

Albrecht presented a paper on the subject called "Microchip-Induced Tumors in Laboratory Rodents and Dogs: A Review of the Literature 1990-2006" (http://www.chipmenot.org/pdfs/P074.pdf) at the June conference of the Institute of Electrical and Electronics Engineers that documents the increasing number of animals being harmed by microchips. Currently, there is no repository of data on adverse events associated with microchips in the U.S., but Albrecht organization, CASPIAN, is filling that void by compiling such information and making it available to the public.

To learn more about the dangers of animal microchips, visit: www.ChipMeNot.org

Sources for this story include:

http://www.chipmenot.org/mercksued.htm

Learn more: http://www.naturalnews.com/030108_microchips_animals.html#ixzz1zccfhZOD