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Showing posts from November, 2005

Virology: A primer on Viruses and "Bird Flu"

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I have recently recieved several questions concerning Viruses in general and the Bird Flu in particular so I thought I would give a short tutorial on the subject. If it's to in depth....sorry, I have a habit of doing that. More in depth info can be found HERE . One way to think of viruses in very small microscopic machines that have the ability to invade your cells, reproduce within them and then exit in mass numbers to infect other cells. If you picture this happening you can see why you feel so bad as this is happening. Once a virus gains access to the body (usually through the respiratory system) it attaches to the surface of the respiratory epithelium ( via the "H" protein, Hemaglutinin) and then inserts itself or is absorbed by endocytosis (cellular engulfing). Once within the cell, the virus begins replication protected from attack by the immune system. Once a significant number (crital mass) of viral particles is obtained within the cell, they are expelled (via &q
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Doc Weldon & Mac 

Cushings Disease...."does this halter make me look fat ?"

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As horses live longer we have to deal with the everymore likely possibility of "cancer". One of these is a small tumor on the Pituitary gland at the base of the brain. The Pituitary gland is responsible for regulation of Hormone production in the body and as tumors develop they cause an abnormal production of these substances. In the Horse this frequently leads to "Cushings Disease" and a wide array of clinical signs such as Laminitis, a long curly hair coat and excessive drinking. The big problem is the laminitis and hoof abcesses which can spell disaster for your horse, the key is picking up the problem early. To do this we do an extensive physical exam to see if this could actually be Metabolic syndrome (another problem) and then do diagnostic testing for organ function and a dexamethasone suppression test. While the tumor itself is not treatable at this point there are medications we can use to control the clinical signs. Primarily we use Cyproheptidine and Per

Equine Influenza, Greyhounds and Bird Flu.

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Things seem to be heating up on the Bird Flu front ( Great Britain ) and ( China ) and it makes you wonder about the development of persistent cross species transfer. There has recently been a similar event seen in Florida where Equine Influenza has been linked to an outbreak of respiratory disease in Greyhounds ( here ). As is the concern in people with Bird Flu, the Greyhounds had no immunity to this virus, and it was severe. When there is no antibody response to an infection it replicates unchecked through the body damaging any system it is geared to. Influenza is primarily a respiratory virus and replicates in bronchial and alveolar epithelium. When these cells are infected they become swollen and leak cellular fluid and eventually slough into the airway. This causes reduced oxygen exchange and excess fluid in the lungs making breathing difficult. Those that die essentially drown. Not a pretty picture. There have been cases where the current Bird flu has been transfered to yet an

Update: Horse stabbing......CSI -Equine

Curiouser and curiouser. The story about the stabbed horse has legs (sorry bout the pun). I had a call from the sister in law last night "I think I just saw your stabbed horse on the news". Yup, there he was...in living color , on the 11:00 news. Now, I don't want to down play the significance of the injury but we are rapidly approaching media saturation with an article on the front page of the Metro section in todays paper and another segment on the evening news tonight. The local station even had a link to a site about the incident that stated that the bills could run as high as $15,000 and ......you could make donations ( NOTE-this wasn't my site). I've looked at my bill and I'm still not sure how you get to that figure. I'm just waiting on the call from Geraldo....... or my attorney.

"Somebody Stabbed my horse!"

Let me start out by saying that this was a new one. I'm never surprized by what some people do to animals (such as HERE ) and I've seen plenty. Like the time someone shot their horse for getting into the garbage, honest I saw it. "I was just tryin' to scare him", sure you were, just tell that to the officer. But last night I got the "stabbed" call. The owner had riden the horse up to the local convienence store and while inside....the deed was done. The horse was tied to a tree and had blood pouring from a wound in the center of the chest while someone(we'll call him the Perp) was running away. It's never a good sign when you arrive to treat an animal and there is a significant police presence, but I did feel better with a "horse-stabber" on the loose. After an exam which revealed a DEEEEP hole in the left pectoral muscle and alot of subcutaneous emphysema (air under the skin along the left side of the body). The good thing was that

Bird Flu ?

In case you didn't know I also have a degree in Microbiology which is why I'm interested in topics like the current "bird flu" scare. Here are some need to know facts 1. It's not in the USA 2. It has not shown an ability to transmit from human to human 3. It can't infect your horse or you....yet. You can find more on this here and here . What you see in the news is a discription of the virus as H & N numbers. This is related to surface makers H= hemagglutinin ( 16 subtypes) and N= neuraminidase(9 subtypes), this one is classified as H5N1. This flu infects birds and has spread to humans working with them in about 160 cases in asia. Of these cases about 40% were fatal, making it a serious world health risk. The buzz word is "pandemic", which is a new disease that spreads from person to person. There have been 3 pandemics in the last 100 years , the first being the flu outbreak at the turn of the last century(1918)and most recently in 1968. The conc