Research News: 02/06

Predicting Barrel-Racing Stresses
Lameness goes with the territory for any hard working equine athlete. While conformation always plays an important role in predisposing horses to specific problems, the type of work being done also tends to result in some problems being much more common than others.

Knowing the areas at highest risk for injury in your sport can be a big help in zeroing in on early lameness problems when you’re not quite sure exactly where, or why, the horse is off.

A recent study done at Texas A & M examined the records of 118 barrel racing horses seen in their clinic for lameness/performance problems. The most commonly reported problem was refusal or failure to turn properly around the first barrel. The breakdown by location of lameness problems found was:

• Right front leg: 48%
• Left front leg: 43%
• Both front: 26%
• Left hind leg: 26%
• Right hind leg: 21%
• Both hind: 5%

The breakdown by location and type of the pain was:

• Front foot pain only: 33%
• Arthritis of the distal tarsal (hock) joints: 14%
• Suspensory ligament problems: 13%
• Both front foot pain and hock problems: 9%
• Bruised feet: 8.5%


Rib Factures In Older Horses
Researchers in the Department of Archeology and Classical Studies at Stockholm University noticed something they think may be important for veterinarians to know. In the process of detailed examinations of the skeletons of registered horses of two native Scandinavian breeds they noticed that fractures were commonly found in portions of rib cartilage that had ossified (turned to bone). Most fractures were found in horses age 15 to 30. The youngest was a 5-year-old. One horse had over 30 fractures. A review of skeletons from other breeds turned up similar findings.

Rib fractures are a recognized problem in foals (e.g. kicks), but rarely mentioned in adult horses. Since the study found these fractures predominantly in older horses, it’s unlikely they were the result of trauma at a younger age.

They’re a common problem in humans with osteoporosis, but this study did not mention possible causes. Rib fractures may need to be added to the list of possible diagnoses for older horses showing unexplained pain, and signs such as reluctance to move, rapid shallow breathing but with a normal lung examination and sensitivity to touch along the lower chest wall.


Antibiotics For Influenza
Although the trend in medicine is to avoid antibiotic treatment with viral infections, a newly released study conducted by the Virology Laboratory of the Butanan Institute in Brazil gives some interesting new information on interaction between influenza virus and bacteria.

They found that infection with flu in pigs, humans and horses was always associated with co-infection with an obscure bacterium. The bacteria were found to have protein cleaving/breaking enzyme activity, which is necessary to activate the influenza virus, increases its ability to enter cells, and increase inflammation. These bacteria may even be able to “turn off” the body’s natural inhibitors of these protease enzymes.

The bacteria were also found to be resistant to antibiotics in almost 50% of the cases. However, tetracycline or doxycline may be particularly good choices.

Tetracyclines are a historical favorite for repiratory-tract infections and often effective even when organisms don’t test particularly sensitive to it. This class of drugs, and in particular low-dose doxycycline, is known to effectively inhibit protease activity.