Apodiformes

Question 1

Majority of lesions in retrospective of hummingbirds in California were associated with which categories?

Do hummingbirds have a gallbladder?

Answer 1

Magagna, M., Noland, E., Tell, L. A., Purdin, G., Rideout, B., Lipman, M. W., & Agnew, D. (2019). Histopathologic findings in free-ranging california hummingbirds, 1996–2017. Journal of wildlife diseases.

• Ingluvies common lesion was mucosal-associated bacterial overgrowth
• Most common liver lesion hepatocyte microvacuolation
• Malaria, cestodes and feather mites found but did not cause significant disease
• Majority of lesions were associated with infections and/or acute trauma
• Significant mortality due to one etiology was not observed
• Hummingbirds one of most susceptible avian families to infrastructure associated mortality
• Birds with chronic, debilitating diseases in worst body condition
• 4/12 birds with cestodiasis were in poor BCS but no histo findings. Others in good BCS
• Hummingbirds have a gallbladder – previously thought to lack one until this study
• Hummingbird heart known for being large and has high cardiac output. Overall heart anatomy in hummingbirds does not differ significantly vs other birds. Possible osseous cardiac skeleton

Question 2

Known risk factor for polydactyly in swifts?

Answer 2

Dogliero, A., Quaranta, G., & von Degerfeld, M. M. (2018). Bilateral Pentadactyly in an Immature Alpine Swift (Tachymarptis melba). Journal of avian medicine and surgery, 32(4), 342-344.

• Young Alpine swift presented to wildlife rehab center
• Bilateral pentadactyly found on exam
• Rads - extra digits appeared to be composed of 2 phalanges
• No motor deficits or discomfort associated with pentadactyly
• Coelioscopy – NSF, determined to be immature male
• Frst described case of bilateral pentadactyly in an Alpine swift
• Pentadactyly reported in 2 other swift species of order Apodiformes 🡪 Vaux’s swift and common swift
• May have been a recessive, sex-linked genetic anomaly
• Alpine swift = order Apodiformes = family Apodidae
• Zygodactylous
• Polydactyly
• thoracic limbs - change in digit form and number
• pelvic limbs - supernumerary halluces
• genetic trait
• dominant genetic trait in domestic fowl
• usually accompanied by motor deficits and other complications (pain)
• known risk factor - high environmental temp during early embryonic development
• any damage to developing ectoderm can predispose to supernumerary digits