Probiotics have been used in poultry for decades and have become common in the pet bird industry. Desirable characteristics of probiotic organisms are that they are nonpathogenic, have the ability to adhere to intestinal epithelial cells, have the ability to colonize and reproduce in the host, have the ability to be host-specific, survive transit through the gastrointestinal tract and exposure to stomach acid and bile, produce metabolites that inhibit or kill pathogenic bacteria, modulate gastrointestinal immune responses, and survive processing and storage. Purported benefits in birds are disease prevention and promotion of growth. Recommendations for use in avian species are for periodic use to replenish normal flora, use after antibiotic therapy to reestablish normal flora, and use during periods of stress to counter effects of immunosuppression.

Pimobendan is a phosphodiesterase (PDE) inhibitor and calcium sensitizer with inotropic, lusitropic, and rasodilator properties used in the treatment of congestive heart failure. The mechanism of action is by inhibition of PDE III and V and by increasing intracellular calcium sensitivity in the cardiac myocardium. Pharmacokinetic and pharmacodynamic studies have been published in humans, dogs, and cats, but there are no studies in avian species. Pimobendan has been used in birds at the empirical dosage of 0.25 mg/kg q12h. To determine the pharmacokinetic parameters of pimobendan in Hispaniolan Amazon parrots (Amazona ventralis), 3 pilot studies with 2 birds, each receiving 1, 3, and 10 mg/kg PO, provided the basis for the pivotal trials with 6 birds, each receiving 10 mg/kg PO using 2 different suspensions. Blood samples were obtained at 0, 0.5, 1, 1.5, 2, 3, 4, 8, 12, and 18 hours after drug administration. Plasma concentrations were determined by liquid chromatography–tandem mass spectrometry (HPLC/MS) by use of electrospray ionization. Because of the erratic and low concentrations of pimobendan, pharmacokinetic parameters were calculated using naive averaged analysis. Plasma concentrations after commercial pimobendan tablet suspension at 10 mg/kg reached a Cmax of 8.26 ng/mL at 3 hours with a terminal half-life of 2.1 hours, while concentrations after the bulk chemical suspension reached a Cmax of 1.28 ng/mL at 12 hours and had a terminal half-life of 2.3 hours. Further studies evaluating the effect of oral pimobendan in parrots are needed.

Veterinary practitioners frequently encounter disorders of the reproductive system in avian patients. Management of these disorders relies on manipulating reproduction by modifying the environment, diet, and social interactions, and by the use of pharmacologic agents and surgery, with varying levels of success and side effects. An alternative is to use the gonadotropin-releasing hormone (GnRH) agonist deslorelin to suppress the pituitary–gonadal axis. To determine the efficacy of deslorelin in domestic pigeons (Columba livia), male (n = 10) and female (n = 10) birds each were implanted intramuscularly with a single long-acting implant containing 4.7 mg deslorelin. Untreated males (n = 11) and females (n = 10) were used as controls. The baseline serum concentration of luteinizing hormone (LH) was assayed at 7, 28, 56, and 84 days after treatment, and egg production was recorded weekly. In females, deslorelin administration significantly reduced serum LH concentrations compared to pretreatment levels at 7, 28, 56, and 84 days (P < .05). In males, deslorelin significantly reduced LH concentrations at 7, 28, and 56 days (P < .05). Female birds treated with deslorelin laid significantly fewer eggs over the course of the study (mean = 1.46, SEM = 0.84) compared with controls (mean = 5.54, SEM = 0.88). Deslorelin treatment had no discernible effect on body weight. Deslorelin is effective for controlling egg laying in female pigeons for at least 49 days, but further research is required to determine the effects on male fertility and the duration of action in both sexes.

A nested case-control study was performed to determine nonmedical risk factors associated with feather picking in psittacine birds. Forty-two case birds, reported by their owners to pick their feathers, and 126 unaffected birds were compared. The odds of feather picking were higher in 2 species categories, African grey parrots (Psitticus erithacus, adjusted odds ratio [OR_adj] = 8.4, P < .001) and cockatoos (Cacatua species, OR_adj = 12.7, P < .001). The odds of feather picking also were higher for birds that were out of their cages more than 8 hours per day (OR_adj = 7.4, P < .001) and for birds that had been taken in by the owner as a “rescue” (OR_adj = 4.7, P < .01). The odds of feather picking decreased by almost 90% (OR_adj = 0.1, P < .005) for birds that interacted with people at least 4 hours a day. These findings identify characteristics that practitioners may want to include when asking bird owners about behavioral history and may be useful in focusing future research regarding this behavior.

The objectives of this study were to determine reference intervals, perform longitudinal analyses, and determine the index of individuality (IoI) of 8 hematologic, and 13 biochemical and electrophoretic variables for a group of captive bald eagles (Haliaeetus leucocephalus). Reference intervals were determined from blood samples collected during annual wellness examinations for 41 eagles (23 male and 18 female) with ages ranging between 6 and 43 years (18.7 ± 7.4, mean ± SD) at the time of sample collection. Longitudinal analyses and IoI were determined for measured hematologic, biochemical, and protein electrophoretic variables, both individually and as a group, for a subset of 16 eagles (10 male and 6 female) during a 12-year period. This smaller group of eagles ranged in age between 2 and 20 years at the start of the study period, and between 14 and 32 years (21.9 ± 5.0, mean ± SD) at the end of the study period. Significant increases with age within the group of 16 eagles were observed only for red blood cells, percent heterophils, total protein, and β-globulin protein fraction, while albumin:globulin decreased significantly with age. A low IoI (≥1.4) was determined for all hematologic and biochemical variables except γ globulins, which had high IoI (≤0.6) for 3 individuals within the subset of 16.

A female American kestrel (Falco spaverius) fledgling was found on the ground with a suspected trauma to the right eye and open-mouth breathing. During the first 2 days of hospitalization, the bird developed severe bilateral periorbital cellulitis, blepharoedema, and sinusitis. The periocular tissues of the right globe were devitalized and communicated with a fistula at the commissure of the right side of the beak. The blepharoedema of the left eye was aspirated and yielded a dark colored malodorous fluid, which was submitted for aerobic bacterial and Mycoplasma cultures. Results showed a mixed infection with Mycoplasma buteonis, Avibacterium gallinarum, and Staphylococcus pasteuri, all of which are not commonly isolated from birds of prey. With antimicrobial therapy, supportive care, and surgical debridement of the right periocular necrotic tissues and adhesed phthisical globe, the kestrel recovered from this severe mixed upper respiratory infection.

A 24-year-old female blue and gold macaw (Ara ararauna) was presented for an acute onset of left head tilt. On examination, the macaw was dehydrated and had a 120-degree left head tilt, decreased proprioception of the left pelvic limb, and intermittent vertical nystagmus. Results of hematologic testing and biochemical analysis revealed severe leukocytosis with lymphopenia and heterophilia and a high uric acid concentration. Radiographs showed bilateral intertarsal joint osteoarthritis and a healed ulnar fracture. Magnetic resonance imaging of the brain revealed focal T2 and fluid-attenuated inversion recovery hyperintense lesions in the right cerebral hemisphere and in the midbrain. The midbrain lesion showed susceptibility artifact on the T2* sequence, suggesting hemorrhage. In the T2* sequence, iron accumulation (as seen with hemorrhage) distorts the magnetic signal, resulting in the production of a susceptibility artifact, which can then be visualized as a region of hypointensity. The bird was hospitalized but died despite intensive care. Necropsy revealed multiple cerebral vascular lesions including an acute cerebral infarct, a ruptured midbrain aneurysm, and multifocal systemic atherosclerosis. To our knowledge, this is the first report of a cerebral aneurysm in a bird. This report correlates the clinical presentation, imaging, and histopathologic findings in a macaw with central vestibular disease and demonstrates how advanced imaging techniques can identify hemorrhagic lesions through the T2* sequence.

An adult male hyacinth macaw (Anodorhynchus hyacinthinus) that presented for acute onset nasal discharge and dyspnea had purulent discharge from the right naris and serosanguineous discharge from the left naris on physical examination. Results of a complete blood count revealed severe leukocytosis with a mature heterophilia. Computed tomography scans showed a large amount of soft-tissue attenuating material within the infraorbital sinus and associated diverticula. Aerobic culture results of the nasal discharge showed a mixed population of Staphylococcus intermedius and Pasteurella species, including Pasteurella pneumotropica; all isolated bacteria were susceptible to enrofloxacin. Clinical signs did not resolve over the course of 9 weeks of antibiotic treatment. The macaw died after cardiopulmonary arrest while hospitalized. At necropsy, a 2 × 2 × 3–cm firm, tan, friable, space-occupying mass surrounded by a thick exudate was present in the left preorbital diverticulum of the infraorbital sinus. The cranioventral one-third of the trachea contained a 4 × 0.5–cm white-yellow plaque. On histologic examination, the sinus mass was diagnosed as a nasal adenocarcinoma, and the tracheal plaque was caused by fungal infection, most likely with an Aspergillus species.

Because the population of yellow-billed loons (Gavia adamsii) is declining, satellite telemetry was used to learn more about the needs of this species and the interdependencies of various populations that breed in isolated regions. In July 2013, the author accompanied a team of biologists to Victoria Island in the Canadian Arctic to surgically implant satellite transmitters in 14 yellow-billed loons. This article chronicles the trip with the objective of connecting the reader with the loons and the interesting people that strive to conserve them.