Can a veterinarian help me?

SkepticSteph

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Jan 16, 2007
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I got this in an email earlier today. Our dog is NOT microchipped yet, because we are waiting for a more "universal" chip. Also, our dog has three ID tags and a rabies tag on his collar, and he always has his collar on. Anyway, is this valid, or complete and utter woo woo?

Implanted Microchips Cause Cancer

By Jane Williams GFN contributing writer---
(For Publication in the January 2007 "American Family Voice")

At the National ID Expo in Kansas City, Arkansas Animal Producer's
Association President Michael Steenbergen asked, "What safety studies
have been conducted on the chips that are inserted into animals?" His
question was met with total silence. Did these manufacturers not know,
or were they unwilling to admit that research has confirmed that
implanted microchips cause cancer?

Melvin T. Massey, DVM (Doctor of Veterinary Medicine)
from Brownsboro,Texas, brought this to the attention of the American
Horse Council when he wrote, "I am a retired Equine Veterinarian and
still breed a few horses. Because of migration-infection s-increased
risk of sarcoids I will not want to have microchips in my horses."

The Institute of Experimental Pathology at Hannover Medical School
in Germany reported , "An experiment using 4279 CBA/J mice of two
generations was carried out to investigate the influence of parental
preconceptual exposure to X-ray radiation or to chemical carcinogens.
Microchips were implanted subcutaneously in the dorsolateral back for
unique identification of each animal. The animals were kept for lifespan
under standard laboratory conditions. In 36 mice a circumscribed
neoplasm occurred in the area of the implanted microchip.
Macroscopically, firm, pale white nodules up to 25 mm in diameter with
the microchip in its center were found. Macroscopically, soft tissue
tumors such as fibrosarcoma and malignant fibrous histiocytoma were
detected."

Ecole Nationale Veterinaire of Unite d'Anatomie Pathologique in Nantes,
France, reported, "Fifty-two subcutaneous tumors associated with
microchip were collected from three carcinigenicity B6C3F1 micestudies.
Two of these 52 tumors were adenocarcinoma of the mammary gland located
on the dorsal region forming around the chip. All the other 50 were
mesenchymal in ori! gin and were difficult to classify on morphological
grounds with
haematoxylin-
eosin."

Marta Vascellari of Instituto Zooprofilattico Sperimentale delle Venezie
at Viale dell'Universita in Legnaro, Italy reported examining a
9-year-old male French Bulldog for a subcutaneous mass located at the
site of a microchip implant. "The mass was confirmed as a high-grade
infiltrative fibrosarcoma,

with multifocal necrosis and peripheral lymphoid aggregates."

The Toxicology Department of Bayer Corporation in Stillwell, Kansas
reported, "Tumors surrounding implanted microchip animal identification
devices were noted in two separate chronic toxicity/oncogenici ty
studies using F344 rats. The tumors occurred at a low incidence rate
(approximately 1%), but did result in the early sacrifice of most
affected animals, due to tumor size and occasional metastases. No
sex-related trends were noted.

All tumors occurred during the second year of the studies, were located
in the subcutaneous dorsal thoracic area (the site of microchip
implantation) and contained embedded microchip devices. All were
mesenchymal in origin and consisted of the following types, listed on
order of frequency: malignant schwannoma, fibrosarcoma, anaplastic
sarcoma, and histiocytic sarcoma.

The following diagnostic techniques were employed: light microscopy,
scanning electron microscopy, and immunohistochemistry. The mechanism of
carcinogenicity appeared to be that of foreign body induced
tumorigenesis. "

Additional studies related to cancer tumors at the site of microchip
implants have been conduced in China; however, at this time these
studies are not available in English. At this time, no long term studies
are available covering more than two years. It only seems logical to
conclude that if carcinogenic tumors occur within one percent of animals
implanted within two years of the implant that the percentage would
increase with the passage of time. Additional studies need to be
conducted, but don't hold your breath for the manufacturers of
microchips to conduct such research and be leery of any such "research"
they may conduct. Even the limited research available clearly indicates
that implantation of microchips within an animal is gambling with the
animal's well being.

For additional Information:
www.vetpathology.org

also
National Library of Medicine and National Institutes of Health,
or just google for "sarcomas associated with implanted microchips".

http://www.louisville-pets.com/micro...cer_study.html
 
I'm not a vet. But I would say it comes down to analyzing risk. What is the risk of a dog being lost or stolen compared to the risk of a dog getting cancer from a microchip? Just from reading a little bit about this, the risk of a dog being lost or stolen by far outweighs the risk of the microchip, but of course that is just my opinion.

I do use microchips in some of my animals, by the way, and have never had a problem. Some of our stock have had microchips their entire lives and then died of old age, not of cancer from the microchip. The species would be llamas, alpacas and horses. We have never once encountered tumors resulting from microchips, nor have any of my friends who also have ranches and raise livestock, and have all their stock microchipped.

Is this possibly in response to the government's program to have all animals in the US microchipped? A lot of people are against this proposal by the government. I wonder if someone is not trying to use the info you have posted to fight said proposal.
 
There are several tricky issues in this statement. I haven't worked on horses for a while but the sarcoid issue sounds like it might be since it is a common skin tumor in horses. The association with the site of the microchip however might just be coincidence. How many horses are implanted and how many have sarcoids occur and how many occur at the site of implant?
The rats or mice getting tumors might be true however many strains of mice are very prone to cancer and some will even get cancer if you inject them with sterile water. I don't have enough knowledge of mice and rats to say much more.
The single dog is nothing significant. How many chips and how many have that tumor? The incidence must be really small however any chronic irritation/inflammation can cause a cancer but the chips aren't particularly inflammation causing as far as I know. I have microchiped hundreds of dogs and cats and no tumors resulting.
Pulling a figure of 1% cancer rate out of the air is total bs.
 
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