Strigiformes Flashcards
Effects of topical rocuronium in kestrels and little owls?
Effect of topical ophthalmic instillation of rocuronium bromide on the intraocular pressure of kestrels (Falco tinnunculus) and little owls (Athene noctuae).
Barsotti G, Asti M, Giani E, Ceccherelli R, Briganti A.
Journal of the American Veterinary Medical Association. 2019 Dec 15;255(12):1359-64.
Background:
Topical parasympatholytic and sympathomimetics do not work in bird eyes because of striated uveal muscles
Topical rocuronium is safe and effective in raptors and Hispanolan Amazons
Pancuronium did not produce mydriasis
Alcuronium bromide has partial mydriasis but also systemic effects
Vecuronium bromide required 3 instillations at 15 min intervals for mydriasis
Ciliary muscle in birds is striated and has 3 fiber groups: anterior (Crampton), internal, posterior
Contraction of Crampton muscle flattens peripheral cornea and flattens central cornea (may impact IOP)
Key Points:
After topical rocuronium instillation in kestrels and little owls,
PLR absent after 60 minutes
IOP decreased after 60 min (little owls > kestrels)
Conclusions: Topical rocuronium will decrease IOP in raptors.
What was observed following treatment of barn owl nests with insecticide (permethrin) in regards to nestling survival rate?
Efstathion, C. A., Burkett-Cadena, N. D., & Kern Jr, W. H. (2019). Prefledging mortality and the abundance of mosquitoes biting nestling barn owls (tyto alba) in florida, usa. Journal of wildlife diseases, 55(3), 597-607.
Significantly fewer mosquitoes were captured from treated nest boxes. Nestlings in insecticide-treated boxes had higher survival rates.
Dominant mosquito spp captured were Culex nigripalpus, Mansonia dyari, Mansonia titillans.
Survival significantly higher for birds in insecticide-tx boxes in Sept and Oct, when mosquito numbers were high. Mortality high regardless in March (assoc with sugarcane harvesting).
What were the effects of isoflurane anesthesia on owl hematology?
Berg, K. J., Whittington, J. K., Watson, M. K., Wiggen, K., Blalock, A., & Mitchell, M. A. (2019). Effects of Isoflurane Anesthesia on the Hematologic Values of Rehabilitated Wild Owls. Journal of avian medicine and surgery, 33(4), 369-380.
Single, short-duration iso exposure = WBC decreased over time under anesthesia; no difference between manual restraint.
Prolonged anesthesia = significantly decreased lymphocytes (increased H:L ratio).
Serial anesthesia events (3d in a row) = Decreased heterophil count.
Decreases in PCV observed in many owl spp.
Overall WBC, PCV remained within normal limits for all owl spp evaluated.
Name vectors for plasmodium, haemoproteus, and leukocytozoon. General LC for plasmodium? Tx for blood and tissue stages?
What strigiform and falconiform species are very susceptible to clinical disease?
Baker, K. C., Rettenmund, C. L., Sander, S. J., Rivas, A. E., Green, K. C., Mangus, L., & Bronson, E. (2018). Clinical effect of hemoparasite infections in snowy owls (Bubo scandiacus). Journal of Zoo and Wildlife Medicine, 49(1), 143-152.
Vectors:
Plasmodium - Culicidae
Haemoproteus - Biting midges aka sand flies (Ceratopogonidae)
Leukocytozoon - Black flies (Simulidae).
Plasmodium relictum and plasmodium elongatum most important.
LC - Replication in host tissues (exoerythrocytic stage), invades circulating blood cells (erythrocytic phase). Inflammation, tissue necrosis, hemolysis and anemia.
Vector control, cooling, reducing handling can decrease disease. Addition of fans, removal of standing water, use of insect growth inhibitors and pyrethrin sprays around enclosure perimeter.
Gyrfalcons and snowy owls very susceptible to clinical disease.
Dx blood smears and PCR.
Tx - Chloroquine (blood stages) and primaquine (tissue stages). Mefloquine and doxycycline have also been used anecdotally.
What tests are available for WNV Ab testing in raptors? What is the gold standard?
Captanian, N., Hawkins, M. G., Fiorello, C., Thurber, M., & Reisen, W. K. (2017). Low prevalence of West Nile Virus antibodies in select northern California owl species (2007–2014). Journal of Zoo and Wildlife Medicine, 48(4), 1239-1241.
Indirect immunoglobulin G enzymes immunoassay (EIA)
Positives should be confirmed with plaque reduction neutralization test (PRNT) = Gold standard
PRNT highly sensitive and specific, but time consuming, labor intensive, expensive.
EIA developed as a screening tool but not specific, cross-reacts with other Flaviviruses to have to confirm with PRNT for WNV - All PRNT positive samples have been shown to be EIA positive.
WNV Ab prevalence virtually absent in owls sampled in northern California.
What can cause uveitis and free air in the anterior chamber of EASOs?
Barron, H. W., Hill, J. M., Dubé, K. M., Riley, J. L., Bast, R. L., Stevens, B. N., & Karpinski, L. G. (2018). Trauma-induced uveitis and free air in the anterior chamber of three eastern screech owls (Megascops asio). Journal of avian medicine and surgery, 32(4), 314-321.
Fractured scleral ossicle from trauma -> acute perforation of globe with free air accumulation in anterior chamber.
All cases resolved with supportive care for head and occular trauma and passed vision testing, were released.
Owls with vision deficits or blindness in 1 eye are still elligible for release.
What is an infectious dz concern when housing psittacines near raptors?
García-del-Río, M., Sancho, R., Martínez, J., & Merino, S. (2021). Blood parasite infections in strigiformes and psittaciformes species in captivity with a new record of potential fatal blood parasite transmission to parrots. Journal of Zoo and Wildlife Medicine, 51(4), 799-813.
Nocturnal raptors have high prevalence of infection by blood parasites, postential for fatal transmission of Haemoproteus syrnii from strigiformes to psittaciformes.
Important to establish prevention measures to avoid hemoparasite transmission. Mosquito nets, keeping birds indoors when possible during periods of high vector activity, repellents and larvicides, routine vet evaluation of blood smears, tx as needed with antimalarials.
What method of goniometry was most accurate and reliable in barred owls?
Gjeltema, J. L., Degernes, L. A., Buckanoff, H. D., & Marcellin-Little, D. J. (2018). Evaluation of Goniometry and Electrogoniometry of Carpus and Elbow Joints in the Barred Owl (Strix varia). Journal of avian medicine and surgery, 32(4), 267-278.
Modified universal plastic goniometer accurate for elbow flexion and extension and carpal flexion with good to excellent reliability vs rads. Electrogoniometer less accurate and less reliable.
Radiographic measurements considered gold standard.
Carpus - Overly and parallel with distal diaphysis of ulna and mid-diaphysis of major metacarpal bone.
Elbow - Parallel and overlying distal diaphysis of the humerus and proximal diaphysis of the ulna.
What was the effect of topical rocuronium bromide on IOP of kestrels and little owls?
Barsotti, G., Asti, M., Giani, E., Ceccherelli, R., & Briganti, A. (2019). Effect of topical ophthalmic instillation of rocuronium bromide on the intraocular pressure of kestrels (Falco tinnunculus) and little owls (Athene noctuae). Journal of the American Veterinary Medical Association, 255(12), 1359-1364.
Mydriasis achieved in all birds.
IOP decreased at 60 min in kestrels and 30 min in owls. Nadir 60 min both spp.
Return to normal pupil diameter at 280 min (5 hrs) for kestrels and 340 min (6 hrs) owls.
Takeaway: Faster onset and longer lasting mydriasis in owls.
A recent study established ophthalmic parameters in burrowing owls.
What is the scientific name of the burrowing owl?
What setting is recommended for tonometry?
Were there sex differences in IOPs?
How well did rocuronium work to dilate the eyes?
JAMS 2022 36(2) 192-199
Ophthalmic Parameters and Ophthalmoscopy of Burrowing Owls (Athene cunicularia)
Bennett K, Osinchuk S, Bauer B, Rao S, Sadar MJ.
Key Points:
- This paper creates a reference for IOP, STT and other ophthalmic observations in burrowing owls
- The D setting read higher IOPs than the P setting; therefore, it is more important to avoid low findings that are incorrect (due to low readings with uveitis) and so it is tentatively suggested that the D setting be used on the TonoVet for burrowing owls
- IOPs in males > females using the D setting
- Rocuronium bromide worked to cause complete dilation in minority of owls, but fundic exam still possible in all owls
A recent paper described a xenotransfusion from a great horned owl to a barn owl.
What are the scientific names of those species?
Blood groups are known for some species in which orders?
What considerations should be made prior to performing a xenotransfusion?
JAMS 2022 36(3) 302-307
Blood Transfusion from a Magellanic Great Horned Owl (Bubo virginianus magellanicus) to a Barn Owl (Tyto alba) A Successful Case of Xenotransfusion
Key Points:
- This report describes a successful case of xenotransfusion from a Magellanic great horned owl to a barn owl
- Xenotransfusion may be used in avian cases that require a blood transfusion when there is no possibility of obtaining blood from a conspecific
- Blood groups in birds have been studied in some species of Galliformes and Anseriformes, but they are still largely unknown in most avian species
- The chosen heterologous blood donor must ideally share similar erythrocyte morphology and dietary habits and only be considered if a donor of closer taxonomical classification is not available at the time
- Crossmatching tests are recommended before each blood transfusion, especially when the bird is receiving blood from a heterologous donor or when receiving a second transfusion
A recent paper described the use of in vivo confocal microscopy to identify fungal keratitis in owls and a woodcock.
What were the clinical signs of these birds?
IN VIVO CONFOCAL MICROSCOPY FOR CHARACTERIZATION OF MYCOTIC KERATITIS IN OWLS (BUBO SCANDIACUS, STRIX VARIA) AND A WOODCOCK (SCOLOPAX MINOR): THREE CASES.
Lucyshyn DR, Childs-Sanford SE, Choi E, Ledbetter EC.
Journal of Zoo and Wildlife Medicine. 2023;54(1):202-210.
Key Points:
- Case series showing use of In vivo confocal microscopy in diagnosis and treatment of 2 owls and 1 woodcock with fungal keratitis
– Noninvasive, highly effective, allows immediate, real-time quantification of extent of corneal infiltration by fungal hyphae
- 2/3 birds had negative fungal cultures and the one with positive culture required enrichment causing 3 wk delay between sample collection and final results
- Clinical findings of aspergillosis keratoconjunctivitis in birds: lagophthalmos, blepharitis, inferior eyelid thickening, yellow-white plaques, caseous exudates, blepharospasm, blepharedema, periorbital swelling, peripheral nerve paresis, corneal ulceration, anterior uveitis
- Main differential: Candida albicans - asper hyphae were longer and had no pseudohyphae or yeast
Conclusions
- In vivo confocal microscopy can be used to identify fungal hyphae in the cornea of birds with keratoconjunctivitis in real time and may be more sensitive than culture.
