Written by Katie McInnis DVM, CWR, Jesse Pline CWR, Riley Gibbons
An adult Red-tailed hawk of undetermined sex was found at Elijah Bristow State Park lethargic and unable to fly. On exam the bird was lethargic, pale, dehydrated (approximately 8%), and emaciated (BCS 1.5/5) weighing only 725 g. Immediately noticeable was that the gnathotheca had been broken off at the tip and there were two ulcerated lesions in the oral cavity. The bird also had severe pediculosis, with feather lice so numerous it was estimated that there were 10-20 adult lice per centimeter. Due to the severity of the lice infestation the hawk was immediately sprayed with a veterinary pyrethrin spray (Vetkem). He was then given warm subcutaneous LRS and placed in an incubator.
That evening the bird was depressed but standing, he was better hydrated, and many dead mites were visible in the incubator. He had not passed any mutes yet, and per the CRC emaciation protocol he was tubed with LRS again to resolve dehydration. The next morning he was rehydrated and standing. He was started on dilute Emeraid Carnivore Care (EC) at a ratio of 2% EC to 3% Pedialyte. This was slowly stepped up over the next few days by increasing the EC% and decreasing the Pedialyte, until the bird was given 5% body weight in EC.
At this point the bird was still lethargic, but it was standing, producing normal mutes, and was a better candidate for anesthesia. To ensure nothing was missed on the physical exam two view, full body radiographs were taken, and an in-house complete blood count and fecal were performed. We also swabbed the ulcerated lesions in the mouth as we were suspicious that they were fungal lesions. No further injuries were noted on radiographs. The fecal sample revealed two different types of parasite eggs (Capillaria sp. +2 and Echinostome sp. +1), while the oral lesions were positive for Candida sp. The bird was also found to be severely anemic and hypoproteinemic with a packed cell volume (PCV) of 12% and a total protein (TP) of 2.4 mg/dL.
Due to his compromised state we chose to treat for both parasites and the fungal lesions, as well as perform a blood transfusion. To perform the blood transfusion, we chose a healthy ambassador bird that was at a high weight to be our donor. Unfortunately, our Red-tailed hawk was not plump enough to donate the amount of blood we needed, so we chose our Ferruginous hawk (Eowyn) as the donor.
Under anesthesia we drew 15 ml of whole blood from Eowyn into a 20 ml syringe that had been pre-heparinized. We then kept the blood warm while we masked down RTHA 24-541. Once the bird was anesthetized, we attached a blood filter and butterfly catheter to our syringe and slowly injected the 15 ml of whole blood into the cutaneous ulnar vein over a three-minute period. The bird was given oxygen while waking from anesthesia and monitored for a transfusion reaction over the rest of the day.
Post transfusion the birds demeanor improved, and it began to consume feedings more readily. It was moved to an outside aviary and continued to improve. A second PCV/TP was done ten days post transfusion with results being in the normal range (PCV: 35% TP: 5.3 mg/dl)
The bird has continued to do well in captive care, going from a low weight of 690g to a current weight of 1105g. We hypothesize that the lower beak injury was severe enough to compromise her ability to prehend food and preen her feathers. This combination led to a lower plain of nutrition and severe feather lice infestation which may have been enough to prevent it from hunting adequately to sustain itself. CRC will continue to hold the bird in our rehab aviaries until the beak has regrown to an adequate level for release.