Fall Reminders

Right now is a great time to get on board with the 'new' deworming program since sometime over the next couple of weeks is the time to submit fall fecal samples. The details of our 'new' deworming recommendations have been discussed previously on this blog and have been posted here on our clinic website.

Now is also the time for fall checkups and vaccines. Typically in the fall we recommend boostering the Flu and Rhino vaccines your horse recieved this spring. The immunity from these vaccines is fairly short lived, thus semi-annual boosters are required. We also usually incorporate Rabies vaccines into the fall visit. The Rabies vaccine in horses requires annual boosters. Rabies is one of those diseases that has since an increased incidence in horses in Michigan over the past couple of years. The disease is always fatal and always poses a significant human health risk to those who come in contact with an infected horse. The vaccines is safe, effective and cheap. There really is no excuse not to vaccinate.

This is also the perfect time of year to schedule the routine dental care for your horses. Fall is the ideal time to provide for your horses dental health as we seek to maximize their feed efficiency through the quickly approaching winter months. The field of equine dentistry has seen significant advances in recent years. We are now better equipped than ever to address oral health issues including bite realignments and treatment of peridontal disease. Dental radiographs can be an invaluable tool in assessing diseased teeth. We believe strongly that your regular veterinarian is your best resource for equine dental care.

See you soon.

Welfare Reform

The ongoing discussions in the both the horse community and legislature about the social consciousness of horse slaughter continues. In 2006, Congress defunded inspection of horse slaughter plants. This act functionally shut down the two remaining horse slaughter plants in the U.S. That act brought discussions about the complexities of animal welfare to the forefront for everyone involved in the equine industry. This past week the GAO released a report asking Congress to either institute a permanent ban on horse slaughter or allow it. This recent report by the GAO has put a renewed light on the horse slaughter debate.

The issue of welfare (the non-entitlement kind) is well beyond the scope of what I can adequately address here. The complexities of the debate about animal welfare is, in large part, fed by individuals different perceptions of what is truly the best welfare option. Last year’s annual meeting of the American Association of Equine Practitioners (AAEP) devoted their keynote address to this topic. As I listened to this presentation it really hit me how stark the disparity is between differing individuals beliefs of what really constitutes the ‘best’ practices of animal welfare. Is protection from natural predators better welfare than free ranging in a ‘natural’ environment? Is a low level of infectious disease better welfare than having social interaction? More poignant to this discussion: is humane slaughter under federal inspection better welfare than malnourishment? is humane slaughter of equids a better option than owner neglect or owner performed euthanasia? is it more humane to use animal products for human consumption or to put a carcass in a landfill? These are complex issues vehemently argued by camps with opposing presuppositions.

Regardless of perspective, this recent GAO report refreshes the discussion of the current stalemate on the horse slaughter issue. According to this most recent GAO report the current plant closures have pushed the horse slaughter market to Canada and Mexico (which do not have the same regulations for humane transport and handling as we do here), have resulted in significantly lower sales prices of lower grade horses and have had a negative impact on the welfare of these horses by greatly increasing the long distance travel times to horse slaughter facilities.

The basic conclusion of the GAO is that we, as a society, need to move out of purgatory and decide on either re-implementing the option of the humane slaughter of horses or move to a formal ban. The current legislation that functionally does an end around on humane slaughter only leaves those seeking to have it overturned, to do so by another legal end around. The result is that the best intentions often end in the worst outcomes.

For a more in depth look at this issue click here

Equine Repro Update

I spent that past couple of days at the Society for Theriogenology annual meeting. If that is a foreign term to you, theriogenology is really just the study of reproduction in animals. This meeting brings together the innovators in this field to present on new and exciting advancements.

One of the most exciting talks I sat in on was discussing the advancements in embryo diagnostics. More specifically, it is now possible to acquire an embryo, biopsy it for genetic testing-either traits or heritable disease-freeze it for indefinite storage and later thaw it for implantation into a recipient mare for her to carry to term. Equine embryos are generally not inherently resilient to manipulation. The group from Texas that presented their advancements in this field have made remarkably astounding advances with embryo biopsy and testing. While much of this is not really commercially available as of yet, just a couple of years ago the levels of success they are now achieving were not even thought possible. Many of these advancements have sprung out of the recent refinement and success of the ICSI procedure, as previously discussed here. Stay tuned.

Another exciting advancement comes out of Colorado. Veterinarians at Colorado State University have developed a PCR test for uterine fungal infections. Uterine infections in horses are usually caused by bacteria. However, on occasion a fungal organism is pegged as the culprit. To this point, fungi have been difficult to reliably culture and identify. Not to mention it can take several weeks to grow them in the lab. This new technology looks for evidence of fungal DNA. They then replicate the DNA in the lab and analyze it to determine the exact type of fungus. This is incredibly useful because results can be achieved in days rather than weeks. Again this test is not yet commercially available, but should be very soon.

Topics that were covered in depth included stallion breeding soundness exams and placentitis. Stallion breeding soundness exams focus on the predictability of a given stallion to be able to produce foals. Despite all of the advancements over the past many years, this still remains a somewhat elusive target. One thing that is becoming increasingly more apparent is that sperm motility does not correlate well with fertility. This goes contrary to historically popular thinking. But the reality is that some stallions have very good motility and poor conception rates, while other stallions have poor motility and yet have reasonable conception rates. That said, we still feel better seeing good motility. The reality is that relating the findings on a breeding soundness exam to future fertility remains ‘complex and multifactorial’- that is medical jargon for we do not yet have a perfect understanding of this. This does not mean that breeding soundness exams are worthless, quite to the contrary. It just means that they are not black and white, and many factors need to be looked at and addressed when considering the current or future breeding soundness of a given stallion.

Researchers continue to explore the complex disease that we have come to call placentitis. Placentitis is an infection of the placenta. The vast majority of the time, bacteria gain entry into the placenta through the cervix of a mid to late term pregnancy. Mares with poor vulvar conformation are particularly at risk. Early identification is crucial to successful treatment. If the injection becomes too extensive the foal can quickly become compromised. The more extensive the infection is the more difficult it is to treat. The best way to look for evidence of a placental infection is ultrasound evaluation of the placenta. This remains our best tool for assessment of placentitis. Treatment usually involves long term antibiotics, anti-inflammatories and progesterone supplementation. There is a lot of new research looking at what are the best medications to use. However, the reality is that successful treatment is tightly correlated with early identification of infection. With this in mind, it may be prudent to screen at high risk mares with ultrasound evaluations of the placenta in late pregnancy.

The last talk I wanted to highlight from this meeting was a presentation by a veterinarian in Argentina who has perfected a large scale embryo transfer program in horses. Embryo transfer is becoming increasing more common. The success rates with embryo transfer continues to improve. The ability to ship recovered embryos to large recipient herds available throughout the U.S. has made this whole venture considerably more practical. There is now an embryo recipient herd here in Michigan (Saginaw) that has been very good for Michigan breeders. The major advantage of a ‘local’ recipient operation is that the cost of shipping and transport of recipient mares is greatly diminished. It also makes it much easier to transport recovered embryos to an ideal recipient because we can now just hop in the car and drive the embryo to its destination, rather than having to rely on the airlines for same day shipment to a recipient herd. Cryopreservation of equine embryos continues to be a challenge. Techniques for improving embryo transfer success and improving efficiencies was covered in great depth.

Even as we are just wrapping up this breeding season, this meeting has reinvigorated me, as I sit in anticipation of next year’s breeding season. The continued advancements in equine reproduction are astounding.

Michigan Coggins Testing Rules Change.....again

The requirements for Coggins testing in Michigan has changed yet again. Earlier this year the prior requirement of annual calendar year testing for horses that are shown or sold expired. That left us without any legal requirement to test. However, shows and fairs still could still require a negative test. Last week the state legislature passed P.A.121 which reinstated the Coggins testing requirement, with a few changes.

A Coggins test is a blood test for a contagious viral disease that affects horses called Equine Infectious Anemia (EIA). EIA is a disease for which there currently is no treatment or vaccine for. As such, infected horses only serve a source of infection to other horses. Testing is the only method of disease control that is available. The disease is a federally regulated disease which requires the test to be submitted and reported on a federally approved form.

Here is the short version of the new law:

1. The following requirments for a negative EIA test do not apply to foals 6 months old or younger.

2. A negative EIA test is now considered current if the blood sample was obtained within the prior 12 months.

2. All horses entered in shows, exhibitions or fairs must have a negative EIA test.

3. Any horse that changes ownership AND location within the State of Michigan must also have a negative EIA test.

4. Any horse entering, remaining or on the premise of any horse auction or market must have a negative EIA test within the previous 12 months.

5. All horses entering the State of Michigan must also be accompanied by a negative EIA test.

The most significant change from the old law is that there is no longer a calendar year requirement. The calendar year requirement was not without reason, but it was a logistical frustration for all of us. This is a welcome change to the law. The caveat to this, is that under the old law many people had their Coggins tests done in January so they would not have to worry about it the rest of the year. Under the new law, your Coggins test for next year will expire one year from when it was drawn. So those who had a Coggins done this past January will have to have next year's Coggins done in January again, if their circumstances meet the requirements of the new law. Click here if you care to know the details of what the requirements used to be.

Look how far we've come

I stumbled across this video that I think you would enjoy. It's really just a quick overview of some of the advances in equine veterinary medicine in recent years. Click here for the link, or go to http://www.myvnn.com/page.asp?id=39&media_type=11&story_id=127

Along the way...

I realize it has been a while since I've made time for a post. This is my best attempt at playing catchup. These are some images I've acquired in my recent travels, that I hope you will enjoy.

Further evidence that veterinarians never know what they will encounter in the course of the day.

This was a large ulcer in the cornea, as demonstrated by the large green area in the center of the cornea. The green area is a stain that we put in the eye that gets taken up by the cornea when the superficial layers of the cornea have been disrupted. You can tell this has been going on for quite a while because of the blood vessels that you can see starting to migrate from the margin of the cornea. The blue haze on the left side of the eye is the result of edema within the cornea. This horse has an unstable tear film which made this a very difficult case to manage.

This is a pair of ultrasound images from a fetal gender determination. This is an incredibly reliable method of determining the gender of a fetus, in utero. It is best done between 60 and 70 days of pregnancy. At this stage of pregnancy gender can be determined by the location of the genital tubercle (labled as GT in these images). In this case the GT is immediately behind the umbilical cord. It can also be seen in the image all the way to the left between the hind legs. This fetus is a colt. If it were a filly the GT would be up under the base of the tail.

The owner of this establishment is presumably is an Appaloosa breeder.

One of the joys of getting up early in the morning is the ability to appreciate the handiwork of God. Note the symmetry in the clouds.

This was a case of cellulitis I saw the other day. The skin was leaking serum, giving the leg a wet, shiny appearance. What looks like wounds are actually areas where the skin is trying to die. This horse responded well to therapy, and is well on his way to a full recovery.

This is an image of a horse's hoof 2 weeks after a hoof wall resection. The severity of this case required that a portion of hoof wall be removed. After removal of the hoof wall, the tissue will fairly quickly keratinize, which is what you see now at the site of the resection. This is a very interesting case that is ongoing. At some point in the future this case will be worthy of its own post. Stay tuned.

"I'm the king of the mountain."

Further evidence of the limitless creativity of horses to incessantly find new and exciting ways to injure themselves.

This is what the wound above looked like after it was put back together.

I love this picture. Count the number of locks on the door. A couple of days before I was at this farm, I was out at another farm at 10:PM treating 5 horses for grain overload. A well secured feed room door represents a significant cost saving over seeing me at 10:PM.

What is your diagnosis? When I arrived at this farm the pony was out on pasture. This was the first thing I saw when I looked in the stall. Notice all of the saliva mixed with chewed up feed. Horses produce an incredible amount of saliva. When the esophagus (the tube that goes from the mouth to the stomach) becomes obstructed, as in a 'choke,' feed and saliva are no longer able to be swallowed. As a result large amounts of saliva and feed will pour out of the mouth. In such cases, a veterinarian should be called immediately.

One of the challenges of dealing with wounds in the summer months is baby flies (otherwise known as maggots).

Baby horses are a lot cuter than baby flies.

Wolf Teeth

The picture to the right is of the right upper dental arcade. The small little tooth at the very front is a wolf tooth. These small little teeth do not serve any known function, other than to get in the way of the bit. For this reason they are typically removed before a young horse goes into training. Occasionally we will encounter an older horse with bit related issues as a result of a wolf tooth left in place.

They can be highly variable in their eruption pattern. Most are about the size of the one in this picture, but they can also be larger or smaller. Most horses have upper wolf teeth, some only have one, and yet some horses never develop them at all. Very rarely will they appear on the lower jaw. They are almost exclusively only on the upper jaw.

Many people get wolf teeth confused with canine teeth. The wolf tooth is technically the first premolar. They sit just in front of the second premolar, which is a very large tooth, and the first major cheek tooth in the dental arcade. The canines sit quite a bit further forward in the mouth, much closer to the incisors. Canine teeth do not appear in the mouth until 4 or 5 years of age. Another difference from wolf teeth is that they are present on both the upper and lower jaws. A properly placed bit would sit behind the canines, but just in front of the wolf teeth. Most mares do not develop canines, but if they do, they are typically quite a bit smaller than what their male counterparts would have. Canine teeth are considerably large than wolf teeth. They are extremely difficult to extract. Canine teeth are only removed if they are diseased. We do not remove healthy canine teeth.

Because wolf teeth do not serve any known function and because they only serve to be a source of irritation in the bitted mouth, we typically removed them prior to a young horse going into training. The picture to the right is the same horse pictured above, except now the wolf tooth has been removed. To extract the tooth we first numb up the area, cut the gum around the tooth and then gradually work to slide it out with an elevator. The small hole left heals over quickly and uneventfully.

Here is what the tooth looks like out of the mouth. You can see that while they have a very small crown, there is a very long root present.