Hearing Assessment of Free-Ranging Owls and Implications for Wildlife Rehabilitation: 31 Cases (2014-2023).

Owls, members of the avian order Strigiformes, are nocturnal birds of prey that are found worldwide except for Antarctica. Traumatized, free-ranging owls are commonly presented to veterinary hospitals and wildlife rehabilitation facilities with the goal of providing medical care and rehabilitation to enable release back into their natural habitat. Minimal guidelines exist for the release of wildlife, and whereas a need for functional vision is described in raptors, assessing and evaluating hearing is usually not mentioned. This can be problematic for nocturnal predators because hearing is the primary sense utilized by owls when hunting and navigating in their dark environment. The brainstem auditory evoked response (BAER) test is a minimally invasive, objective assessment of hearing commonly used in companion animals. To the authors' knowledge, routine or standardized BAER evaluation has not been reported in traumatized, free-ranging owls. In the following retrospective study, 31 free-ranging owls presented to the University of Georgia Veterinary Teaching Hospital for known or suspected trauma or being found in a debilitated state underwent BAER testing to assess for the presence of complete sensorineural hearing loss. Similar to assessment of hearing in companion animals, the BAER test was elicited using a broad click stimulus delivered at 85 dB nHL. In all owls, qualitative assessment and peak latency measurements of the BAER test reflected hearing ability. This study highlights the importance of hearing in nocturnal raptors, how BAER testing can aid in decision making regarding rehabilitation, and provides a foundation for further investigation of hearing loss in traumatized owls. We suggest that veterinarians working with free-ranging owls in a rehabilitation setting should consider BAER testing as part of routine diagnostic testing.

THE USE OF THE LIGASURE™ DEVICE FOR SCROTAL ABLATION IN MARSUPIALS.

Five sugar gliders ( Petaurus breviceps ), ranging in age from 3 mo to 3.5 yr of age, and one opossum ( Didelphis virginianus ), age 4.5 mo, presented for elective orchiectomy and scrotal ablation. The LigaSure™ device was safely used for orchiectomy and scrotal ablation in both species. Surgical time with the LigaSure was approximately 4 sec. No grooming of the incision site or self-mutilation was seen in the first 72 hr postoperatively. One sugar glider required postoperative wound care approximately 10 days postoperatively following incision-site grooming by a conspecific. The LigaSure provides a rapid, technologically simple and safe surgical technique for scrotal ablation and orchiectomy in the marsupial patient that minimizes surgical, anesthetic, and recovery times.

BILATERAL HYDRONEPHROSIS IN A SUGAR GLIDER (PETAURUS BREVICEPS).

An adult, intact male sugar glider ( Petaurus breviceps ) presented for acute caudal abdominal swelling. Treatment by the referring veterinarian included aspiration of urine from the swelling. On physical examination, mild depression, pale mucus membranes, and caudal abdominal swelling were noted. Focused ultrasonographic assessment revealed a fluid-filled caudal abdominal structure and subjective bladder wall thickening. The following day, the sugar glider was severely depressed. Hematology results included hypoglycemia, hyperkalemia, hyponatremia, and azotemia. Ultrasonography revealed bilateral hydronephrosis and hydroureter. Despite supportive care, the animal died. Postmortem examination confirmed bilateral ureteral dilation, renal petechial hemorrhage, and dilation of the right renal pelvis. Submucosal edema, hemorrhage, and lymphoplasmacytic infiltration of the urinary bladder, ureters, and renal pelvises were noted. Hyperplasia of the urinary bladder and ureteral epithelium, coupled with inflammation, may have caused functional obstruction leading to bilateral hydronephrosis and hydroureter. This is the first reported case of hydronephrosis in a marsupial.

Diagnostic imaging of peripheral vestibular disease in a Chinese goose (Anser cygnoides).

A 20-year-old Chinese goose (Anser cygnoides) presented for severe left-sided head tilt and circling to the left. Peripheral vestibular disease associated with otitis media extending into the left quadrate bone was diagnosed by magnetic resonance imaging and computed tomography. Otoscopy confirmed a ruptured tympanic membrane, and a brainstem auditory evoked response test confirmed loss of hearing in the affected ear. Surgery to remove the caseous material and long-term medical therapy improved the bird's head tilt and quality of life. Otitis, hearing loss, and vestibular disease are rare in birds but can be managed after appropriate investigation. This is the first reported use of multiple advanced diagnostic tests and successful treatment of vestibular disease in a goose.

Pharmacokinetics of Levetiracetam in Healthy Hispaniolan Amazon Parrots ( Amazona ventralis ) After Oral Administration of a Single Dose.

Long-term anticonvulsive treatments have been poorly described in birds, and few pharmacokinetic studies have been performed, with mixed results. Levetiracetam, a new anticonvulsive drug, has shown good efficacy for monotherapy or adjunctive treatment of seizures in both human and veterinary medicine. To determine pharmacokinetics of levetiracetam in Hispaniolan Amazon parrots ( Amazona ventralis ), 20 healthy birds were randomly divided into 2 groups and administered either a 50 mg/kg (n = 10) or a 100 mg/kg (n = 10) oral dose of levetiracetam with no observable adverse effects. Blood samples were collected at baseline and at 12 time intervals (6 per group) for 16 hours. The concentration-time profiles resembled characteristic absorption, with maximum plasma concentrations of 61.0 µg/mL and 95.1 µg/mL at 60 minutes; terminal half-lives at 2.38 and 2.37 hours; volumes of distribution of 0.807 and 0.773 L/kg, with an area under the curve at 14 100 and 28 820 mg × min/L; and clearance rates of 3.65 and 3.60 mL/min per kg, respectively. Plasma concentrations were greater than 5.5 mg/L for up to 9.4 and 12 hours, suggesting an 8- and 12-hour oral dosing at 50 and 100 mg/kg, respectively, would be sufficient to maintain targeted values. Clinically, doses and frequencies may need escalation based on differences in species and individuals, and drug levels should be monitored.

Impact of apitherapy on canine, equine, and chicken lymphocytes, in vitro.

Apitherapy is a form of alternative medicine that utilizes products from the western honeybee (Apis mellifera), including honey, propolis, and honeybee venom, to improve the health status of human patients by altering host immunity. An added benefit of these products is that they are nutraceuticals and relatively inexpensive to aquire. Currently, little is known about the use of honeybee products in veterinary species, as well as their impact on host immunity. In the present in vitro study, honey, propolis, and honeybee venom were co-cultured with enriched canine, equine, and chicken peripheral blood lymphocytes (PBLs) with cell proliferation, cell viability/apoptosis, and cellular morphology evaluated. Concanavalin A (Con A) and dexamethasone were used as stimulatory and suppressive controls, respectively. Honeybee products' effects on the three veterinary species varied by product and the species. Honey stimulated the PBLs proliferation in all three species but also displayed some increased cytotoxicity. Propolis stimulated proliferation in canine and equine PBLs, however, it suppressed proliferation in the chicken PBLs. Honeybee venom was the strongest PBL stimulant for all three species and in the equine, surpassed the stimulant response of Con A and yet, enhanced PBL cell viability post culture. In summary, the results of this preliminary in vitro study show that these three honeybee products do impact lymphocyte proliferation and viability in dogs, horses, and chickens, and that more research both in vitro and in vivo will be necessary to draw conclusions regarding their future use as immune stimulants or inhibitors.

Evaluation of an 18-micron filter for use in reptile blood transfusions using blood from American alligators (Alligator mississippiensis).

Blood transfusions are a common therapeutic procedure in small animal medicine and have been investigated in some exotic species but little information is available about their safety and efficacy in reptiles. In human pediatrics and small animal practice, the Hemo-Nate18-micro filter is used to prevent embolic clots and particulate waste from entering the recipient during a transfusion. The goal of this study was to determine the hemolytic effect of an 18-micro Hemo-Nate filter for whole blood cell transfusions in reptiles using the American alligator (Alligator mississippiensis) as a reptilian model. Results revealed no significant difference in free plasma hemoglobin between the unfiltered and filtered samples (P = 0.21). There was no difference in the prefiltration and postfiltration packed cell volume (PCV) (P = 0.41). Results suggest that an 18-micro Hemo-Nate filter does not cause hemolysis or decrease the PCV of small quantities of alligator blood.

Honeybees as a teaching tool in veterinary education.

Veterinary education is becoming more and more complex, but the ultimate goal-providing an education that will prepare students for entry-level positions in the profession-remains the same. Often, hands-on work with living animals aimed at achieving core competencies is relegated to the final year of the veterinary curriculum. But, incorporating honeybees allows introduction of these important concepts during earlier years of veterinary student training. In addition, honeybees are under severe threat from a multitude of health problems, and this has dire implications for our own food supply. Veterinarians need to be actively involved in addressing this health crisis. Ever since the US FDA implemented its Veterinary Feed Directive rule, which dictates how certain antimicrobials can legally be administered in the feed or water of food-producing animals, and made changes to its policy on the use of medically necessary antimicrobials on bees, honeybees have fallen under the direct purview of veterinarians, highlighting the need for greater literacy in honeybee health. The present manuscript describes reasons why and ways how honeybees can play a larger role in the education of veterinarians in the United States.

Proposed grading scheme for inflammatory bowel disease in ferrets and correlation with clinical signs.

Inflammatory bowel disease (IBD) is an idiopathic, chronic, inflammatory disease of the gastrointestinal tract of companion animals, including ferrets (Mustela putorius furo). Clinical signs of IBD are nonspecific, and intestinal biopsies are necessary for a definitive diagnosis. A grading scheme has not been established for ferrets. Additionally, the association between histologic severity and clinical signs in ferrets is unknown. We evaluated enteric samples from ferrets diagnosed with IBD, compared histologic grading schemes, and correlated the results with the severity of clinical signs. Enteric sections from 23 ferrets with IBD were analyzed using grading schemes for intestinal inflammation in cats and dogs, and a correlation with clinical signs was evaluated. After dividing the histologic samples into groups based on the severity of clinical signs, main histologic differences were identified. Age and sex were also assessed for correlation with clinical signs. No significant correlation was found between the 2 grading schemes and clinical signs (rho = 0.02, p = 0.89; rho = 0.26, p = 0.18, respectively). Degree of villus fusion, hemorrhage and/or fibrin, epithelial damage, inflammation density, and crypt abscess formation were used retrospectively to create a ferret IBD grading scheme, which was significantly correlated with the severity of clinical signs (rho = 0.48, p = 0.01). A positive correlation was observed between age (p = 0.04) and females (p = 0.007) with severity of clinical signs. Our ferret grading scheme may have clinical utility in providing a more objective, consistent evaluation of IBD in ferrets.

Mandibular squamous cell carcinoma in 2 psittacines.

A unilateral, malformed gnathotheca in a green-winged macaw (Ara chloropterus) was managed for 16 mo with periodic beak trims. Biopsy of the affected beak did not identify an underlying cause; however, at postmortem examination, a densely cellular neoplasm invaded the mandible from the beak, dissecting and effacing the cortex and trabecular bone and inciting periosteal proliferation. There was no evidence of metastasis. Neoplastic cells were strongly immunopositive for cytokeratin AE1/AE3, consistent with squamous cell carcinoma (SCC). A black-headed caique (Pionites melanocephalus) was presented with a similar clinical history, timeline, and gross appearance. Biopsy of the mandibular portion of the lesion resulted in a diagnosis of SCC. Medical management with toceranib at a palliative dose resulted in adverse side effects and was discontinued. Early diagnosis of mandibular SCC may allow for early intervention and development of treatment modalities. Our 2 cases suggest that the mandibular bone, not the beak, may be a preferred biopsy site in the diagnosis of mandibular SCC in psittacines.

Computed tomographic and ultrasonographic diagnosis with successful excision of a lipoma in a shusui koi (Cyprinus carpio).

CASE DESCRIPTION: A client-owned 12-year-old 10.3-kg (22.7-lb) female shusui koi (Cyprinus carpio) was evaluated because of an ulcerated mass on the left body wall, hyporexia, and decreased activity. CLINICAL FINDINGS: The patient was anesthetized with a solution of eugenol in water for all examinations and procedures. An approximately 7 × 5-cm smooth, raised, ulcerated, and firm mass was present ventral and lateral to the dorsal fin on the left body wall. Whole-body CT images obtained before and after contrast administration revealed an encapsulated, homogeneous, fat-opaque mass within the muscle. The mass was fat echoic with poor vascularity on ultrasonographic examination. Histologic evaluation of an ultrasound-guided needle biopsy specimen was suggestive of a lipoma. TREATMENT AND OUTCOME: The mass was excised, and the fish was placed in water with 0.3% salinity for 3 weeks after surgery. Postoperative antimicrobial administration was not indicated, and additional postoperative analgesic administration was considered impractical. The patient had noticeable improvement in appetite and activity with no indication of discomfort immediately following surgery. Five weeks after surgery, the incision site had healed with minimal scarring, and evaluation of CT images revealed no evidence of mass regrowth or regional osteomyelitis. CLINICAL RELEVANCE: Antemortem evaluation and diagnosis of a lipoma in a teleost with subsequent excision was described. This report highlighted the logistic challenges associated with anesthesia, advanced diagnostic imaging, and surgery in fish and showed that they can be successfully overcome so that high-level medical care can be provided to such patients.

Immunomodulatory effects of dietary IMUNO-2865 in mice, pre-and post-vaccine challenge with parainfluenza virus 5.

Herbal remedies and nutraceuticals continue to be used as treatments for a variety of maladies ranging from joint disease to obesity. IMUNO-2865 is a natural nutraceutical supplement that has been advertised to modulate inflammation, boost cytokine activity promoting a robust immunity, but has yet to be evaluated as an adjuvant. In the present study, 4-week-old C57BL/6 female mice (n = 45) were fed 0, 5 or 50 mg/5 g tablet IMUNO-2865 (I-2865) in a tablet formulated feed. One group of mice (n = 15, 5 mice/diet) were placed on a feed diet for 14 days, while the other group of 30 mice (10 mice/diet) were placed on the diet for 28 days. Five mice from each diet group in the 28-day feeding trial were vaccinated on day 7 with a mouse recombinant parainfluenza virus to mimic viral challenge. On days 0, 14 and 28 blood samples were collected. Mice were humanely euthanized on days 14 and 28. Spleens were collected to analyze organ weight/body weight ratios, cell recovery, T cell and B cell phenotype, cell proliferation, antibody titers and cytokine production. Administration of dietary I-2865 for 14 days had no effect on murine immunity. In the 28-day dietary vaccine trial, I-2865 supplementation did not enhance vaccine response, based on vaccine antigen-specific IgG titers, nor did it alter T cell and B cell phenotype, function or cytokine response, but it did decrease splenocyte numbers in the vaccinated mice.

Effects of an enrofloxacin-silver sulfadiazine emulsion in the ears of rabbits with perforated tympanic membranes.

OBJECTIVE: To determine whether an enrofloxacin-silver sulfadiazine emulsion (ESS) labeled for treatment of otitis externa in dogs has ototoxic effects in rabbits following myringotomy. ANIMALS: 6 healthy adult New Zealand White rabbits. PROCEDURES: Rabbits were anesthetized for brainstem auditory-evoked response (BAER) tests on day 0. Myringotomy was performed, and BAER testing was repeated. Saline (0.9% NaCl) solution and ESS were then instilled in the left and right middle ears, respectively, and BAER testing was repeated prior to recovery of rabbits from anesthesia. Application of assigned treatments was continued every 12 hours for 7 days, and rabbits were anesthetized for BAER testing on day 8. Rabbits were euthanized, and samples were collected for histologic (6 ears/treatment) and scanning electron microscopic (1 ear/treatment) examination. RESULTS: Most hearing thresholds (11/12 ears) were subjectively increased after myringotomy, with BAER measurements ranging from 30 to 85 dB in both ears. All day 8 hearing thresholds exceeded baseline (premyringotomy) values; results ranged from 30 to 85 dB and 80 to > 95 dB (the upper test limit) in saline solution-treated and ESS-treated ears, respectively. All ESS-treated ears had heterophilic otitis externa, epithelial hyperplasia of the external ear canal, various degrees of mucoperiosteal edema, and periosteal new bone formation on histologic examination. Scanning electron microscopy revealed that most outer hair cells in the ESS-treated ear lacked stereocilia or were absent. CONCLUSIONS AND CLINICAL RELEVANCE: Results supported that ESS has ototoxic effects in the middle ear of rabbits. Further research is needed to confirm these findings. Myringotomized laboratory rabbits may be useful to study ototoxicity of drugs used in human medicine.

The complementarity of the technical tools of tissue engineering and the concepts of artificial organs for the design of functional bioartificial tissues.

Although tissue engineering uses powerful biological tools, it still has a weak conceptual foundation, which is restricted at the cell level. The design criteria at the cell level are not directly related with the tissue functions, and consequently, such functions cannot be implemented in bioartificial tissues with the currently used methods. On the contrary, the field of artificial organs focuses on the function of the artificial organs that are treated in the design as integral entities, instead of the optimization of the artificial organ components. The field of artificial organs has already developed and tested methodologies that are based on system concepts and mathematical-computational methods that connect the component properties with the desired global organ function. Such methodologies are needed in tissue engineering for the design of bioartificial tissues with tissue functions. Under the framework of biomedical engineering, artificial organs and tissue engineering do not present competitive approaches, but are rather complementary and should therefore design a common future for the benefit of patients.

Gross and histologic evaluation of effects of photobiomodulation, silver sulfadiazine, and a topical antimicrobial product on experimentally induced full-thickness skin wounds in green iguanas (Iguana iguana).

OBJECTIVE To assess effects of photobiomodulation, silver sulfadiazine, and a topical antimicrobial product for the treatment of experimentally induced full-thickness skin wounds in green iguanas (Iguana iguana). ANIMALS 16 healthy subadult green iguanas. PROCEDURES Iguanas were anesthetized, and three 5-mm cutaneous biopsy specimens were obtained from each iguana (day 0). Iguanas were randomly assigned to 2 treatment groups, each of which had a control treatment. Wounds in the topical treatment group received silver sulfadiazine, a topical antimicrobial product, or no treatment. Wounds in the laser treatment group received treatment with a class 4 laser at 5 or 10 J/cm2 or no treatment. Wound measurements were obtained daily for 14 days. Iguanas were euthanized, and treatment sites were evaluated microscopically to detect ulceration, bacterial contamination, reepithelialization, necrosis, inflammation, fibrosis, and collagen maturity. RESULTS On day 14, wounds treated with a laser at 10 J/cm2 were significantly smaller than those treated with silver sulfadiazine, but there were no other significant differences among treatments. Histologically, there were no significant differences in ulceration, bacterial infection, reepithelialization, necrosis, inflammation, fibrosis, and collagen maturity among treatments. CONCLUSIONS AND CLINICAL RELEVANCE Photobiomodulation at 10 J/cm2 appeared to be a safe treatment that was tolerated well by green iguanas, but it did not result in substantial improvement in histologic evidence of wound healing, compared with results for other treatments or no treatment.

Anodized titanium and stainless steel in contact with CFRP: an electrochemical approach considering galvanic corrosion.

The combination of different materials in an implant gives the opportunity to better fulfill the requirements that are needed to improve the healing process. However, using different materials increases the risk of galvanic coupling corrosion. In this study, coupling effects of gold-anodized titanium, stainless steel for biomedical applications, carbon fiber reinforced polyetheretherketone (CFRP), and CFRP containing tantalum fibers are investigated electrochemically and by long-term immersion experiments in simulated body fluid (SBF). Potentiodynamic polarization experiments (i/E curves) and electrochemical impedance spectroscopy (EIS) of the separated materials showed a passive behavior of the metallic samples. Anodized titanium showed no corrosion attacks, whereas stainless steel is highly susceptibility for localized corrosion. On the other side, an active dissolution behavior of both of the CFRPs in the given environment could be determined, leading to delaminating of the carbon fibers from the matrix. Long-term immersion experiments were carried out using a set-up especially developed to simulate coupling conditions of a point contact fixator system (PC-Fix) in a biological environment. Electrochemical data were acquired in situ during the whole immersion time. The results of the immersion experiments correlate with the findings of the electrochemical investigation. Localized corrosion attacks were found on stainless steel, whereas anodized titanium showed no corrosion attacks. No significant differences between the two CFRP types could be found. Galvanic coupling corrosion in combination with crevice conditions and possible corrosion mechanisms are discussed.

Spontaneous spinal plexiform perineurioma in a juvenile chicken ( Gallus domesticus).

A 2-mo-old pet chicken ( Gallus domesticus) was presented because of lameness and a hind limb mass of 1 mo duration. Radiographs revealed a soft tissue mass extending from the mid-femur into the body wall. Cytology of a sample obtained from a fine-needle aspirate was unremarkable. The bird was prepared for surgical investigation of the mass but died acutely at the time of pre-medication. Autopsy revealed an extradural mesenchymal neoplasm that focally compressed the lumbar spinal cord, extended into and along the adjacent nerve structures, and displaced the kidneys, skeletal muscle, and body wall. Histopathology was consistent with a perineurioma, which was positive for alcian blue and negative for S100, GLUT1, and neurofilament proteins on immunohistochemistry. PCR testing of tumor tissue was negative for gallid herpesvirus 2 (Marek's disease virus) and avian leukosis virus. Although the etiology of the mass was not determined, our case highlights a severe manifestation of an uncommonly diagnosed tumor in the chicken. Though uncommon, perineurioma should be considered a differential diagnosis for lameness in the chicken.

Diagnosis and management of pyothorax in a domestic ferret (Mustela putorius furo).

OBJECTIVE: To describe the diagnosis, management, and outcome of pyothorax in a domestic ferret (Mustela putorius furo). CASE SUMMARY: A domestic ferret was evaluated for a history of lethargy, anorexia, and pyrexia. Pleural effusion was detected with radiography and ultrasonography, and a diagnosis of pyothorax was made following cytologic evaluation of pleural fluid. Bilateral thoracostomy tubes were placed for thoracic drainage and lavage, and the ferret was treated with intravenous crystalloid fluids, antimicrobials, and analgesics. Bacterial culture of the pleural fluid yielded Fusobacterium spp. and Actinomyces hordeovulneris. This treatment protocol resulted in resolution of pyothorax, and a positive clinical outcome. NEW OR UNIQUE INFORMATION PROVIDED: This is the first reported case of successful management of pyothorax caused by Fusobacterium spp. and A. hordeovulneris in a ferret.

Enhancing the mechanical integrity of the implant-bone interface with BoneWelding technology: determination of quasi-static interfacial strength and fatigue resistance.

The BoneWelding technology is an innovative bonding method, which offers new alternatives in the treatment of fractures and other degenerative disorders of the musculoskeletal system. The BoneWelding process employs ultrasonic energy to liquefy a polymeric interface between orthopaedic implants and the host bone. Polymer penetrates the pores of the surrounding bone and, following a rapid solidification, forms a strong and uniform bond between implant and bone. Biomechanical testing was performed to determine the quasi-static push-out strength and fatigue performance of 3.5-mm-diameter polymeric dowels bonded to a bone surrogate material (Sawbones solid and cellular polyurethane foam) using the BoneWelding process. Fatigue tests were conducted over 100,000 cycles of 20-100 N loading. Mechanical test results were compared with those obtained with a comparably-sized, commercial metallic fracture fixation screw. Tests in surrogate bone material of varying density demonstrated significantly superior mechanical performance of the bonded dowels in comparison to conventional bone screws (p < 0.01), with holding strengths approaching 700 N. Even in extremely porous host material, the performance of the bonded dowels was equivalent to that of the bone screws. For both cellular and solid bone analog materials, failure always occurred within the bone analog material surrounding and distant to the implant; the infiltrated interface was stronger than the surrounding bone analog material. No significant decrease in interfacial strength was observed following conditioning in a physiological saline solution for a period of 1 month prior to testing. Ultrasonically inserted implants migrated, on average, less than 20 microm over, and interfacial stiffness remained constant the full duration of fatigue testing. With further refinement, the BoneWelding technology may offer a quicker, simpler, and more effective method for achieving strong fixation and primary stability for fracture fixation or other orthopaedic and dental implant applications.

Pacemaker implantation in a ferret (Mustela putorius furo) with third-degree atrioventricular block.

A 7.5-year-old castrated male ferret (Mustela putorius furo) was diagnosed with third-degree atrioventricular (AV) block. A monopolar epicardial pacemaker system was implanted, resulting in a regular, paced cardiac rhythm with third-degree AV block at 140 beats per minute. Over the next 2 months, the ferret developed anorexia, interstitial pneumonia, intermittent diarrhea, and hind-limb weakness and had a slow and progressive recovery. The ferret developed clinical signs of congestive heart failure 4 months after the surgery, resulting in its death 3 weeks later. Necropsy results attributed the death to cardiac failure due to extensive myocardial mineralization. To the authors' knowledge this is the first published report of surgical report of surgical pacemaker implantation in a ferret.