Working donkeys in Kenya need upper airway evaluations, yet equipment and hygiene limitations can make this task challenging. Anya Floyd, DVM, BSc, of Energy Equine Veterinary Services, in Alberta, Canada, described how to use a borescope double wrapped with sanitary sheaths to easily perform this task in less-than-ideal field conditions. Upper airway borescope examinations might help improve the welfare and working conditions of these animals.

“Donkeys are extremely hard-working animals,” said Floyd during her presentation at the 2024 American Association of Equine Practitioners Convention, held Dec. 7-11, in Orlando, Florida. “Their primary duty is pulling very heavy carts, and these carts and the harness system are rudimentary, tied directly to the neck below the jaw using feed sacks, rope, old pants … anything owner can find. Not surprisingly, this harness system can negatively affect the respiratory system, impacting welfare.”  

Uing an Accessible Borescope for Upper Airway Endoscopy in Donkeys

Recognizing the importance of examining the respiratory tracts of these animals, Floyd and her supervisor Martha Mellish, DVM, Dipl. ACT, of the Department of Health Management at Atlantic Veterinary College, in Prince Edward Island, Canada, purchased a simple 1.5-meter flexible borescope capable of capturing videos and images. The major concerns were:

1. Keeping the scope clean as it passed through the upper airways
2. Cross contamination when there was no reliable access to clean water, only alcohol towelettes

Floyd and her team used two disposable artificial insemination (AI) sanitary sleeves to double-wrap the borescope. Specifically, they cut one sleeve below the perforation, creating an opening at both ends of the sleeve. They fixed this open end was fixed to the camera (at the tip of the borescope) using electrical tape. The second AI sanitary sleeve had a sealed end, which they placed over the camera end to protect it while it was passed through the upper respiratory passages.

“Once the borescope was advanced through the ventral meatus (the widest and shortest nasal passage), the camera was advanced through the outer AI sleeve, revealing a completely clean scope and lens, ready to go,” said Floyd.

None of the donkeys were halter broke, so the veterinarians needed to apply chemical restraint and a nose twitch for the procedure.

Testing the Diagnostic Capabilities of the Borescope

Floyd performed 80 scopes in the field using this technique. She considered the scopes diagnostic if she could view the arytenoid cartilage, vocal folds, epiglottis, and trachea to a depth of 40 centimeters to 60 cm from nares (nostrils).

Unlike horses, “donkeys have narrow nasal passages compared to their head sizes, have fleshy and bulbous arytenoids, and the epiglottis is pointed,” said Floyd.

Lubricating the borescope to facilitate its passage helped limit trauma and hemorrhage during the procedure. Elevating the head made passing the scope easier as well.  

One inherent limitation the veterinarians discovered was the borescope’s excessive flexibility. It sometimes got kinked in an “S” shape the team couldn’t correct, so they had to withdraw the scope and reset it.

Take-Home Message

Performing upper airway endoscopy exams in working donkeys is important for their overall health and welfare; however, traditional endoscopes are not always available in some regions. Therefore, borescopes, which can be more easily purchased, might be a useful alternative when endoscopes are unavailable. “The borescope does not fully replace a traditional endoscope but can provide diagnostic data for respiratory health in donkeys,” said Floyd.