Abstract
Background: Donkeys in East Africa are recognized as working with poorly
designed harnesses and carts. The donkey cart used in regions of Africa,
specifically Meru County, Kenya, appears to place the cart’s weight
solely on the donkey’s mid-cervical region where the trachea is
superficially located. Objectives: To compare the presence and severity
of endoscopic abnormalities in the upper airway and trachea of Meru
County working cart donkeys compared to pack donkeys. To determine
associations between endoscopic and external physical exam findings.
Study design: Cross-sectional Methods: At voluntary health clinics,
physical examination and endoscopy of the upper airway and trachea were
evaluated and recorded at rest on 66 donkeys (38 cart donkeys and 28
pack donkeys). The presence and grade of tracheal collapse, tracheal
ring abnormalities, tracheal mucous and pharyngitis were subsequently
determined on the endoscopy recordings by blinded evaluators.
Mann–Whitney and Chi-square/Fisher’s exact tests were used to
investigate associations between work type and physical exam and
endoscopy findings. Results: Significant associations were identified
between work type and tracheal collapse severity, ring abnormalities,
pharyngitis, skin lesions, and skin hypertrophy with these findings more
common in cart than pack donkeys (all P<0.03). Moderate tracheal
collapse (grade 3) was present in 40% (95% CI: 24-57%) of cart and
0% (0-12%) of pack donkeys. Exam findings were significantly and
positively associated with endoscopy findings (all P<0.002).
Main limitations: Standing endoscopy was performed at rest, not dynamic
endoscopy during the pulling of carts. Conclusion: Moderate tracheal
collapse was seen in cart donkeys when compared to pack donkeys.
Physical exam findings at rest were associated with tracheal collapse
and tracheal ring abnormalities. This work may help identify by physical
examination donkeys that are at greatest need of improved harnesses.