Statin drugs are the most effective class of hypolipidemic and antiatherosclerotic drugs, with atorvastatin and rosuvastatin being the most effective. While the use of statins would be a tremendous asset in the treatment of dyslipidemia and lipid-accumulation disorders in birds, there are only limited data available regarding their use and effectiveness in psittacine species. Two consecutive randomized crossover trials on Quaker parrots (Myiopsitta monachus) were performed to study the effect of atorvastatin and rosuvastatin. Ten birds were used in an initial balanced crossover experiment with 5 oral treatments (control; atorvastatin 10 mg/kg q12h and q24h; rosuvastatin 10 mg/kg q12h and q24h) for 2 weeks each. Plasma lipidomics and lipoprotein profiling were performed after each treatment. Twelve birds were used in a second experiment consisting of 2 parallel crossover studies, each with 6 birds either fed their regular diet or a 0.3% cholesterol diet. In the 2 parallel crossover studies, the treatment group was administered atorvastatin 20 mg/kg orally q12h and the control group a placebo suspension orally q12h. Plasma lipidomics, lipoprotein profiles, and 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase activity were subsequently measured. Results were analyzed with serial linear mixed models and trends were assessed graphically. No statistically significant effect of any statin treatment was detected on plasma lipids, lipoproteins, creatinine kinase, or HMG-CoA reductase activity. In the first trial, all the rosuvastatin treatments led to some nonsignificant decreases in several triacylglycerol species, while in the second trial this was only observed in the birds on atorvastatin 20 mg/kg q12h being fed their regular diet. Quaker parrots may require much higher doses of statin drugs to show significant and clinically useful lipid-lowering effects.

Across the Americas, great horned owls (Bubo virginianus) are often presented to veterinarians for conditions requiring pain management. Although recent studies have evaluated opioid drugs in raptor species, information in Strigiformes is lacking. The objective of this study was to evaluate the analgesic effect and duration of action of hydromorphone hydrochloride, a full µ-opioid receptor agonist, in great horned owls. In a randomized, blinded, balanced crossover study, 6 adult birds (5 females and 1 male) received hydromorphone (0.3 and 0.6 mg/kg) or saline (0.9% NaCl) solution (0.03 mL/kg; control) in the left pectoral muscle, with a 7-day washout interval between treatments. Each bird was assigned an agitation-sedation score, and the thermal foot withdrawal threshold (TFWT) was measured at predetermined times before (t = 0 hours) and after treatment administration (t = 0.5, 1.5, 3, and 6 hours). Measurements of the TFWT were obtained with a test box equipped with a thermal perch, which delivered a gradually increasing temperature 40–62°C (104–143.6°F) to the right plantar surface of the owl's foot. Compared with controls, hydromorphone at 0.3 mg/kg dose resulted in significantly higher mean TFWT at 0.5 hours (P < 0.001), 1.5 hours (P = 0.003), and 3 hours (P = 0.005), whereas the 0.6 mg/kg dose resulted in significantly higher mean TFWT from 0.5 hours (P = 0.035) to 1.5 hours (P = 0.001). Both hydromorphone doses were associated with a significant change in the agitation-sedation score (P = 0.001), consistent with mild to moderate sedation. Two owls were observed tremoring after administration of the 0.6 mg/kg dose, which was not noted after the 0.5-hour timepoint; no other adverse effects were identified. This study offers scientific evidence to support the use of a µ-opioid agonist in great horned owls for pain management. Pharmacokinetics and other pharmacodynamic studies of other pain models evaluating hydromorphone and other opioid drugs in this species are still needed.

Nutritional support in malnourished animals is an essential aspect of wildlife rehabilitation; this support is especially relevant when providing lifesaving nutrition to endangered species such as the African penguin (Spheniscus demersus). This study investigated the short-term effects of a commercially available, semi-elemental, critical care diet compared with a hand-made fish formula. Twenty-one African penguin chicks were selected on admission to the Southern African Foundation for the Conservation of Costal Birds in Cape Town, South Africa, in November 2015. Initial assessment included body weight, a full clinical exam, white blood cell count, packed cell volume, and total plasma protein. Ten animals received the commercial critical care diet, whereas a control group of 11 animals were fed hand-made formula for the 2-week study period. All animals were weighed daily and blood sampling was repeated after 14 days. The median weight of both groups increased significantly over 14 days (critical care diet χ² = 10.1, P = 0.002; control χ² = 7.4, P = 0.006). The difference was not significant between the groups for start weight (χ² = 0.1, P = 0.725) or end weight (χ² = 0, P = 1.000) and was not significantly different in the change over time for either absolute numbers (χ² = 1.7, P = 0.193) or percent gain (χ² = 0.8, P = 0.36). The values for packed cell volume, total plasma protein, and white blood cell count increased in all animals after the 14-day study period was complete. On the basis of the results of this study, it was determined that the differing diets led to similar weight gain.

Vasectomies render a male sterile and have been used for various management purposes, including conservation efforts. This report evaluated 4 different surgical approaches (external approach, internal approach with dissection, internal approach with cautery, and internal approach caudally) to perform 177 vasectomies in Texas bobwhite (Colinus virginianus texanus; n = 171) and northern bobwhite quail (Colinus virginianus; n = 6) in a field setting. Birds were not randomized into groups for the different approaches. Survival was recorded in 83% (147/177) of the birds. The most common cause of death was hemorrhage from the common iliac vein due to damage during the surgical procedure. Other causes for death included transection of the ureter, parasitism, euthanasia, and undetermined causes. The approach that had the highest survival rate (89.8%, 132/147) was the internal approach with cautery, and based on these results the authors recommend this approach for vasectomies in Texas and northern bobwhite quail.

A retrospective cross-sectional study was performed to measure the prevalence of avian intertarsal inflammation over a 5-year period, identify risk factors, and discuss treatment options. The authors hypothesized that: 1) long-legged birds would be more affected, 2) participation in a bird show would be a significant risk factor, and 3) young animals would be more frequently affected. Thirty-five clinical cases from 9 avian orders were included in the study. Statistical analysis indicated that the orders Ciconiiformes (9/150; 6%, 95% confidence interval [CI]: 3.2–11), Gruiformes (4/132; 3%, 95% CI: 1.2–7.5), and Pelecaniformes (7/152; 2.8%, 95% CI: 1.4–5.6) were significantly more affected than other orders (P < 0.01). Similarly, long-legged birds (21/35) had 9.8 times greater chance (P < 0.001, 95% CI: 4.7–21) of developing the condition compared with other birds. Participation in a free-flight show (22/35) was a significant risk factor (P < 0.001; odds ratio: 7.0, 95% CI: 3.3–15). Mean age at onset of clinical signs was 5.7 years, and being < 2 years-of-age during the study period was not a significant predictor of disease (P = 0.054). The tibial cartilage, a fragile fibrocartilaginous structure, was frequently affected (34%, 12/35). Treatment protocols included anti-inflammatory drugs, analgesic drugs, or both (94%, 33/35), low-level laser therapy (54%, 19/35), joint immobilization (34%, 12/35), intra-articular corticoid injections (20%, 7/35), surgical stabilization (17%, 6/35), physiotherapy (9%, 3/35), intra-articular hyaluronic acid (6%, 2/35) or platelet-rich plasma (3%, 1/35) injections, and chiropractic care (3%, 1/35). Overall recovery rate was 49% (17/35), and the condition was associated with a poor prognosis in chronic cases.

Over a 3.5-year period, tissue samples from 141 companion and aviary birds with clinically suspected, naturally occurring solid neoplasms were collected via surgical biopsy (n = 53) or at necropsy examination (n = 88) from a population of birds presenting to an avian veterinary clinic in Melbourne, Australia. Neoplastic processes were identified in 73.7% (n = 104) of samples, with 83.7% (n = 87) being interpreted as malignant neoplasia and 16.3% (n = 17) being interpreted as benign neoplasia. The overall estimated prevalence of neoplasia in the study population (n = 5125) was 2.45% (95% confidence interval, 2–2.97%). The gastrointestinal and reproductive tracts were the most commonly affected systems. The most common presenting signs were nonspecific and included lethargy, coelomic distension, and inappetence. In 59 cases, fine-needle aspirates (FNAs) and impression smears were also obtained and evaluated cytologically. The accuracy of cytology for detecting neoplasia in birds and for determining whether a neoplastic process was benign or malignant was assessed by using histopathology as the “gold standard.” There was complete agreement between the cytological and histopathological diagnoses in 72.8% (43/59) of cases. Cytology correctly identified 87.5% of these cases (35/40) as malignant neoplasms and 55.6% (5/9) as benign processes. There was no significant difference between the use of cytology and histopathology for the detection of malignant neoplasia in birds (P = 0.185). The accuracies of FNAs and impression smears for examining avian tumors were also compared. Overall, the best cell preservation was obtained by performing impression smears from tissues, with 62.2% (n = 28) returning high cellularity for cytological examination, compared to 53.8% (n = 14) when samples were obtained by FNA. This study provides an overview of the types and prevalence of neoplasms in a captive bird population from Australia, correlates physical examination findings with tumor types, and provides evidence that cytology is a reliable preliminary diagnostic tool for detecting neoplasia in birds.

Plasma electrophoresis is an ancillary diagnostic tool in avian medicine, with agarose gel electrophoresis (AGE) and capillary zone electrophoresis (CZE) being the most common techniques. Frozen samples can be used for quantitative studies or comparative diagnostic purposes, but stability of avian plasma proteins under freezing is poorly described. To evaluate the influence of plasma freezing on electrophoretograms in white storks (Ciconia ciconia), heparin blood was sampled from 30 individuals during annual health examinations. Plasma samples were obtained after centrifugation of fresh samples and divided into aliquots. Both AGE and CZE were performed on fresh aliquots. The remaining aliquots were frozen at –20°C (–4°F) or –180°C (–292°F) and thawed following different protocols: 1 freeze/thaw cycle after 6 months at –20°C; 1, 2, 4, and 7 cycles over 12 months at –20°C; and 1 cycle after 18 months at –180°C. For both techniques, electrophoretic profiles obtained from these thawed aliquots were compared to fresh electrophoretograms. Quantitatively, significant differences (P < 0.05) in most fractions were seen from 6 months postfreezing at –20°C for both techniques. Fewer statistically significant differences were observed after 18 months under cryogenic preservation (–180°C). Qualitatively, AGE provided more repeatable and stable results than CZE over time on samples stored at –20°C, and electrophoretograms were stable after 18 months of cryogenic storage. An electromigration distortion associated with freezing was seen with CZE only. Plasma samples stored in a conventional freezer (–20°C) should not be compared to fresh plasma. For quantitative studies, cryogenic storage should be privileged.

A 3-year-old male saker falcon (Falco cherrug) was presented with a history of hyperflexion of the first digit of the left pelvic limb with what appeared to be a hypercontracted distal end of the deep digital flexor tendon (m. flexor hallucis longus). Conservative treatment, bandaging, and splinting techniques failed to resolve the hypercontraction of the deep digital flexor tendon and improve digit function. Intraoperatively, the deep digital flexor tendon was found to have formed adhesions with the tendon sheath as well as the bone and soft tissue structures underneath it, impeding its ability to move freely within the tendon sheath. The adhesions were surgically resolved, and the tendon was lengthened by hemisectioning the deep digital flexor tendon at its distal end. Postsurgically, the digit was maintained in an extended position by bandaging. Mild physiotherapy was provided at 5-day intervals to retain function and prevent adhesions. Digit extensibility and function were restored to nearly normal levels after 4 weeks.

An approximately 6-month-old domestic pigeon (Columba livia domestica) was presented for lethargy and an inability to perform its first molt. The pigeon was obese, had anatomical characteristics of a chick, including cere and plumage, and had a ventral coelomic soft tissue mass. Initial blood work was unremarkable. A computed tomographic scan confirmed excessive fat deposition in the coelom and a mass adherent to the liver. A fine-needle aspirate of the mass indicated fat accumulation. A thyroid-stimulating hormone (TSH) test was planned for this pigeon and 3 presumed euthyroid pigeons. Each pigeon was administered 80 µg (∼230 µg/kg) of recombinant human TSH. Blood was drawn at time 0 and 3 and 6 hours after administration of recombinant human TSH. Plasma total thyroxine (TT₄) was measured in duplicate with an in-house analyzer and a reference laboratory. After recombinant human TSH administration, healthy pigeons showed a 4- to 21-fold increase in TT₄, whereas the hypothyroid pigeon had all values <0.12 µg/dL. The pigeon was prescribed 20 µg of compounded levothyroxine twice daily. In the following months, the pigeon molted and developed adult features. The ventral coelomic soft tissue mass disappeared and repeated computed tomography scans showed a decreased amount of body fat and a reduction in the size of the coelomic mass. Levothyroxine was further adjusted multiple times according to additional TT₄ testing to a dose of 2.5 µg once daily. The pigeon has been under treatment with levothyroxine for more than 2 years. Here we present the first reported case of confirmed hypothyroidism in a pigeon. Diagnosis with a TSH stimulation test was unequivocal, even when only considering the results of the in-house analyzer. Levothyroxine treatment resolved clinical signs and could be titrated to an appropriate dose.