treatment | Horse Racing Free Tips

Two Game-Changing Discoveries Suggest New Treatment For Horses Suffering From Uveitis

Globally, equine recurrent uveitis (ERU) is the most common cause of blindness in horses. The painful condition was not well understood until recently, but two new discoveries are providing hope for horses suffering from the disease.

Leptospira is often the bacterial infection behind ERU. Leptospirosis can be carried by small rodents that excrete leptospira in their urine, which can contaminate a horse's water and food. Standing water poses an increased risk of leptospira infection. Leptospires can survive in a horse's kidneys and eyes for extended periods. ERU is the result of a systemic infection; it can occur months to years after acute infection.

Drs. Bettina Wollanke, Hartmut Gerhards and Kerstin Ackermann reported that a chronic leptospiral infection in the eye cavity is only possible through biofilm formation. Biofilm is a thin, slimy film of bacteria that adheres to a surface.

Though antibiotics are often used in ERU treatment, biofilm bacteria are often resistant as the biofilm acts as a literal barrier to the infection. Additionally, the specific type of bacteria and antibiotic, as well as growth conditions, all play a role in how effective antibiotics can be.

This explains why ERU episodes are sporadic as well as why they can last for many years. It also explains why clinical signs may occur months or years after the systemic infection.

The trio concluded that ERU can be treated by the removal of the vitreous material that fills the middle part of the eye, where leptospirosis can reside undetected for years. The researchers note that it is important to determine that the horse is suffering from ERU and not another form of uveitis, in which case the removal of the material may not be helpful.

[Story Continues Below]

The study team notes that if the eye does not improve that surgery may be needed.

More research is needed. Read more at HorseTalk.

The post Two Game-Changing Discoveries Suggest New Treatment For Horses Suffering From Uveitis appeared first on Horse Racing News | Paulick Report.

Source of original post

Double Down: Traditional Deworming Increases Drug Resistance At Alarming Rate

Traditional deworming methods dictate that all horses on a farm be dewormed with moxidectin or ivermectin at specific intervals, usually every other month or quarterly. Though significantly easier on farm managers, this method increases anthelmintic resistance two to three times more rapidly than other deworming programs, reports The Horse.

Dr. Thomas Geruden, with Zoetis in Belgium, said these results are not surprising as the worm population is continuously pressured for selection of survivable genes in the calendar-based deworming routine.

Geurden and other researchers in Belgium, along with scientists at the Gluck Equine Research Center in Lexington, Ky., studied two farms that utilized the standard deworming protocol on their Belgian draft horses.

The deworming schedule should have corresponded with the timeline of worm egg development, but drug resistance has caused the worm eggs to appear twice as fast as expected.

Fecal egg counts on every horse on the farm were performed every two weeks from April to September for three years. Horses that had more than 250 eggs per gram of manure were given pyrantel embonate, an alternative dewormer. All other horses were treated with standard anthelmintics in the spring and fall, reducing their deworming by half or two-thirds.

The researchers used the fecal egg counts, both before and after treatment, to create a model of worm life cycles that could predict drug resistance over the next 40 years. The team found that the alternative dewormer maintained low egg counts in all horses and slowed drug resistance in worms by 200 to 300 percent.

The scientists also found that the horses considered “high shedders” of worms were almost always under 5 years old. This knowledge might allow horse owners and caretakers to target which horses may need fecal egg counts run more often – and which may need more-frequent treatments.

[Story Continues Below]

The data suggests that fecal samples should be gathered for egg counts between 42 and 56 days after the spring moxidectin/ivermectin treatment, with a second sample taken between days 98 and 112. These numbers will help determine future egg counts and reduce deworming frequency.

The ability to model the rate of anthelmintic resistance using different deworming protocols has been helpful when discussing deworming with both horse owners and vets, the researchers found. A deworming plan specifically tailored to a farm may be more expensive initially, but the less-frequent, targeted deworming will pay off financially in the long run as dewormer resistance slows.

Are There Any Disadvantages To Popular PPID Treatment?

Pituitary Pars Intermedia Dysfunction (PPID or Cushing's disease) is a disease that affects many older horses, but it can often be controlled with the use of a medication called Pergolide.

In other parts of the world, Pergolide is used in human medicine to combat the symptoms of Parkinson's disease, restless leg syndrome, and hyperprolactinemia. Side effects can include fibrotic lesions of the atrioventricular valves in the heart.

Dr. Heidrun Gehlen, from the Department of Veterinary Medicine at the Free University of Berlin, gathered a team of scientists to determine whether the same effects would be seen in horses.

The scientists examined 23 horses between 19 and 30 years old, all of which had been diagnosed with PPID using the ACTH adrenocorticotrophin hormone test. The treatment group comprised 12 horses that had been receiving Pergolide for between 14 days and 6 years, while 11 other horses in the control group received no Pergolide.

The researchers performed an echocardiographic exam on all horses, and found that each was free of cardiovascular disease; no valve defects were found.

[Story Continues Below]

Follow-up exams were then given to nine horses in the treatment group and five in the control group between three and eight months later. The findings were the same: use of Pergolide did not affect ventricular function or cause valve disease in horses.

Standing Surgery A Non-Traditional Option For Severe Colic Cases

Colic is a very real concern to horse owners. An overarching term applied to any abdominal pain, over 80 percent of colic cases can be resolved without surgical intervention.

The standard colic surgery needed for horses which do require medical intervention involves putting the horse under general anesthesia, laying him down and opening the horse along his ventral midline. This type of surgery carries additional risk to the horse and adds significantly to the cost of treatment.

A new study has found that a flank incision, made while the horse is standing, may be a good option for specific types of colic. This type of surgery is less risky to the horse and less of a financial strain for the owner.

Dr. Marco Lopes and a study team reviewed records of 26 horses and ponies and one donkey which underwent a standing flank laparotomy between 2003 and 2020. The main reason for the decision to utilize this particular surgery was financial.

Though seven animals were euthanized due to an untreatable condition or a poor chance of survival, 20 of the 30 horses with treatable conditions survived. The surviving horses suffered from small intestine impaction or inflammation, large colon displacement (specifically nephrosplenic ligament entrapment), and sand impaction.

[Story Continues Below]

Small colon impaction has already been found to respond well to the standing-flank incision method of treatment.

Study authors found that there are limitations to the surgery. These include:

The horse must remain still during the operation; one in intense pain from severe colic may not be able to have his pain controlled well enough to complete the surgery
Peritoneal cavity and abdominal organ access is not as good as with a typical ventral midline incision
A second incision on the opposite flank may be necessary

The team concluded that a standing flank laparotomy may be a viable approach for abdominopelvic exploration in horses with colic related to the small intestine, cecum, large colon, and peritoneum.