Experimental diet-induced atherosclerosis in Quaker parrots (Myiopsitta monachus).

Spontaneous atherosclerosis is common in psittaciformes, and clinical signs associated with flow-limiting stenosis are encountered in pet birds. Nevertheless, a psittacine model of atherosclerosis has not been developed for research investigations. Sixteen captive-bred Quaker parrots (Myiopsitta monachus) were used in this study. While 4 control birds were fed a maintenance diet, 12 other birds were fed an atherogenic diet composed of 1% cholesterol controlling for a calorie-to-protein ratio for periods ranging from 2 to 8 months. The birds were euthanized at the end of their respective food trial period. Histopathology, transmission electron microscopy, and cholesterol measurement were performed on the ascending aorta and brachiocephalic and pulmonary arteries. Plasma lipoproteins, cholesterol, and triglycerides were also measured on a monthly basis. Significant atherosclerotic lesions were induced within 2 months and advanced atherosclerotic lesions within 4 to 6 months. The advanced lesions were histologically similar to naturally occurring lesions identified in the same parrot species with a lipid core and a fibrous cap. Ultrastructurally, there were extracellular lipid, foam cell, and endothelial changes. Arterial cholesterol content increased linearly over time. Plasma cholesterol and low-density lipoprotein (LDL) significantly increased over time by an average of 5- and 15-fold, respectively, with a shift from high-density lipoprotein to LDL as the main plasma lipoprotein. Quaker parrots also exhibited high plasma cholesteryl ester transfer protein activity that increased, although not significantly, over time. This experiment demonstrates that in Quaker parrots fed 1% cholesterol, advanced atherosclerosis can be induced relatively quickly, and lesions resemble those found in other avian models and humans.

Feather-picking psittacines: histopathology and species trends.

Histologic findings are described for 408 feather-picking or self-mutilating psittacines with the use of biopsies from clinically affected and unaffected skin. Inflammatory skin disease was diagnosed in 210 birds, and traumatic skin disease was diagnosed in 198 birds. Criteria used for the diagnosis of inflammatory skin disease included the presence of perivascular inflammation in the superficial or deep dermis of clinically affected and unaffected sites. The primary histologic criteria for the diagnosis of traumatic skin disease were superficial dermal scarring with or without inflammation in the affected sites and an absence of inflammation in the unaffected sites. The inflammatory cells associated with the lesions were typically lymphocytes and occasionally plasma cells, histiocytes, and granulocytes. A preponderance of inflammatory skin disease was seen in macaws (Ara spp.) and Amazon parrots (Amazona spp.). A preponderance of traumatic skin disease was seen in cockatoos (Cacatua spp.) and African grey parrots (Psittacus erithacus). The prevalence of each was approximately equal in several other species, including conures (Aratinga and Pyrrhura spp.), eclectus parrots (Eclectus roratus), quaker parrots (Myiopsitta monachus), cockatiels (Nymphicus hollandicus), parakeets (Cyanorhamphus and Psittacula spp.), and caiques (Pionites spp.). No geographic or gender-based trends were identified. These findings could be helpful for identifying and treating birds with feather-picking disorders.

Parkinson's disease patients who fracture their neck of femur: a review of outcome data.

Parkinson's disease patients are at increased risk of falls and osteoporosis. They present a challenge to those who treat them for fracture neck of femur. There are conflicting views as to whether they have a worse prognosis, compared to age matched controls. This review discusses their care, including surgical approach and technique, to post-operative management and complications. It highlights the limitations in evidence and the need for further research.

Detection and confirmation of reptilian adenovirus infection by in situ hybridization.

Adenovirus infections are documented in at least 12 different species of reptiles. In contrast to their mammalian and avian counterparts reptilian adenoviruses are not well characterized as to their pathogenic potential and their ability to cause primary disease. In the diagnostic setting, fresh tissues are often not available for virus isolation, and the confirmation of reptilian adenovirus infections is dependent largely upon electron microscopy for the identification of intranuclear viral inclusions associated with histopathologic changes. The diagnosis of adenovirus infection in 2 different species of snake was confirmed by the application of DNA in situ hybridization. Using an aviadenovirus specific oligoprobe, adenoviral DNA was observed in the nuclei of hepatocytes, Kupffer cells, endothelial cells, and enterocytes. Electron microscopy of the liver confirmed the presence of intranuclear viral particles morphologically consistent with an adenovirus. DNA in situ hybridization on formalin-fixed tissues can serve as a suitable alternative to electron microscopy in the diagnosis of reptilian adenovirus infections. Both affected snakes had other concurrent diseases, suggesting that the adenovirus may not have been the primary pathogen.

Doxycycline plasma concentrations in macaws fed a medicate corn diet.

A trial was conducted to determine the doxycycline plasma concentrations attained by feeding a medicated corn diet to large psittacine birds. Doxycycline is the preferred drug for the treatment of chlamydiosis in psittacine birds. Healthy macaws were fed a 0.1% doxycycline-medicated corn diet for 45 days, and plasma doxycycline concentrations were determined by microbiological assay on treatment days 3, 15, 30, and 45. Plasma doxycycline concentrations exceeded 1 microgram/ml in 87% of the samples assayed. As blood concentrations of 1 microgram/ml are considered therapeutic, a doxycycline-medicated corn diet may be efficacious in the treatment of chlamydiosis in large psittacine birds.

Sarcocystis falcatula of opossums: transmission by cockroaches with fatal pulmonary disease in psittacine birds.

Old World psittacines experienced an acute fatal illness in outdoor breeding collections in South Florida. Toxoplasma-like organisms were found histologically in pulmonary capillaries and elsewhere. Because the organisms underwent schizogony and could not be transmitted to mice, we looked for a cause other than Toxoplasma gondii. An opossum was trapped on the premises of 1 facility and was found to be shedding sporocysts similar to Sarcocystis falcatula in its feces. Cockroaches were prevalent and suspected as transport hosts. Cockroaches that had ingested opossum feces and subsequently were fed to cockatoos induced an identical fatal illness. Obstruction of pulmonary capillaries by developing schizonts and pulmonary edema were the most important pathologic findings. The epidemic was stopped by biological insect control employing flightless chickens to reduce cockroach populations and by an electric fence restricting access of opossums to these outdoor psittacine breeding facilities.

Pharmacokinetics of amikacin in African gray parrots.

Amikacin sulfate was administered to African gray parrots at 3 dosages (5, 10, and 20 mg/kg) via 2 routes (IV and IM). The elimination half-time was approximately 1 hour (range, 0.9 to 1.34 hour). The apparent bioavailability of IM administered drug was 61 to 106% and was not dose-related.

Feather and beak dystrophy and necrosis in cockatoos: clinicopathologic evaluations.

Several species of imported and captive-bred southeast Asian cockatoos with feather and beak disease (FBD) were evaluated. In recently emerging stained feathers from affected birds, intracytoplasmic magenta to basophilic inclusions of various sizes were found in macrophages and basophil-like cells within the pulp and feather epidermis. Occasionally, amphophilic intranuclear inclusions were seen within degenerated feather epidermal cells. On the basis of electron microscopic findings, intracytoplasmic inclusions were not membrane bound and consisted of crystalline arrays of viral particles (17 to 22 nm in diameter). On the basis of size and conformation, viral particles most closely resembled those of parvovirus or picornavirus. Consistent hematologic or serum enzyme differences were not found among affected or healthy cockatoos. Compared with findings in healthy cockatoos, cockatoos with FBD had significantly lower serum protein concentrations, and results of serum protein electrophoresis indicated that birds with FBD had significantly lower concentrations of prealbumin and gamma-globulin fractions. Mean pre- and post-ACTH plasma corticosterone concentrations of cockatoos with FBD were not significantly different from those of healthy cockatoos. In 8 of 9 affected cockatoos evaluated, serum T4 concentrations before and after thyrotropin stimulation were considered normal.

Endocrine responses of healthy parrots to ACTH and thyroid stimulating hormone.

Effects of exogenous ACTH on plasma corticosterone and cortisol concentrations and the effects of thyroid stimulating hormone (TSH) on plasma triiodothyronine (T3) and thyroxine (T4) were determined in the following 3 species of parrots: red-lored Amazon (group 1), blue-fronted Amazon (group 2), and African gray (group 3). Each bird was given ACTH (0.125 mg/bird) IM, except for 3 to 4 birds in each group, which were given saline solution (controls). Blood samples were collected before and 90 minutes after ACTH stimulation. In group 1 (n = 12), mean plasma corticosterone concentrations increased significantly (P less than 0.001) from 1.06 microgram/dl (before ACTH) to 4.89 micrograms/dl (after ACTH); mean corticosterone concentrations increased in the control birds from 1.06 microgram/dl to 1.84 microgram/dl; and mean cortisol concentrations increased only slightly from 0.228 microgram/dl to 0.266 microgram/dl. In group 2 (n = 12), mean corticosterone concentrations increased significantly (P less than 0.001) from 2.09 micrograms/dl to 10.58 micrograms/dl; control mean corticosterone concentrations decreased slightly from 2.09 micrograms/dl to 1.77 microgram/dl; and mean cortisol concentrations increased from less than or equal to 0.16 microgram/dl to 0.266 microgram/dl. In group 3 (n = 12), mean plasma corticosterone concentrations increased significantly (P less than or equal to 0.001) from 2.33 micrograms/dl to 4.67 micrograms/dl; mean control plasma corticosterone concentrations decreased from 2.33 micrograms/dl to 1.68 microgram/dl; and plasma corticol concentrations were not detectable. Each bird was given TSH, IM (1 U/bird). Blood samples were collected before and 6 hours after TSH administration. Saline solution was not administered as controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunization against psittacine pox.

Pox virus isolated from psittacine birds was used as a vaccine in trials with love birds (Agapornis roseicollis). The vaccine was applied by wing-web puncture using single- and double-needle applicators. Immunity was effective against challenge with virulent psittacine pox virus administered via the feather follicle/thigh. When unvaccinated contact control birds were placed with the vaccinated individuals immediately post-vaccination, virus spread was evident. However, susceptible birds placed with vaccinated ones at 27 days postvaccination remained uninfected for 11 weeks. The importance of a high vaccine virus titer was observed.

Effect of exogenous ACTH on serum corticosterone and cortisol concentrations in the Moluccan cockatoo (Cacatua moluccensis).

The effects of exogenous adrenocorticortrophic hormone (ACTH) on the serum corticosterone and cortisol concentrations were determined in 28 mature Moluccan cockatoos (Cacatua moluccensis), a representative of the psittacine species. Birds were randomly assigned to 4 groups (2 ACTH-treated groups and 2 saline-treated controls). Group I (10 cockatoos [5 males and 5 females] ) was given 15 IU of ACTH after blood samples (base line) were taken at 10:00 AM. Blood samples were taken again at 30 minutes and 2.5 hours after ACTH administration. Group II (10 cockatoos) was given similar treatment, but blood samples were taken at 1 and 4 hours after ACTH was administered. Groups III and IV (each of 4 birds) were given saline solution injections as controls. Blood samples were taken at 30 minutes and 2.5 hours after injection (group III) and at 1 and 4 hours after injection (group IV). All serum samples were analyzed for cortisol and corticosterone. Serum corticosterone concentration increased significantly (P less than 0.01) from base-line levels (26 ng/ml) to 108 ng/ml within 30 minutes after ACTH was administered. The high values were maintained for 3 hours and then decreased to 40 ng/ml at the end of 4 hours. Male birds seemed to respond to the ACTH treatment quickly and maintained increased concentration for a shorter period when compared with the responses seen in female birds. Serum cortisol values remained low throughout the experimental period. These results indicate that serum corticosterone was responsive to ACTH administration, but cortisol was not. In addition, there may be a difference in the responses between male and female members of the species.

Amebiasis in red-footed tortoises.

Of 500 red-footed tortoises imported to southern Florida, approximately 200 died during a 2-month period. Clinical signs were nonspecific and included anorexia, listlessness, and watery diarrhea, with lingering death. Necropsy consistently revealed thickened duodenum, with necrotic mucosa and multifocal to diffuse areas of hepatic necrosis. Histologic evaluation of tissues demonstrated numerous amebae in intestinal and hepatic lesions.

Panophthalmitis and otitis interna in fire-bellied toads.

Microbiologic and histologic studies were made of fire-bellied toads with signs of ocular and central nervous system disease. Providencia alcalifaciens, Citrobacter freundii, Aeromonas hydrophila, and other gram-negative bacilli were isolated from the eyes and multiple tissues of ill toads. The histologic evaluations revealed severe panophthalmitis and otitis interna.

Survey of bacteriologic flora of conjunctiva and cornea in healthy psittacine birds.

A total of 151 eyes from healthy psittacine birds were examined by bacteriologic cultural methods. Bacterial growth was not found in 41% of eyes cultured, Staphylococcus epidermidis was found in 25%, alpha-hemolytic streptococci in 25%, Corynebacterium spp in 7%, and Staphylococcus aureus in 5%. Each of the following organisms were found in 1% of the eyes; Pasteurella spp, Actinobacillus spp, Escherichia coli, Klebsiella spp, Enterobacter spp, Pseudomonas spp, Proteus spp, and Bacillus spp. More than one bacterial species was found in numerous eyes. Psittacines from an import station had a greater occurrence of ocular bacterial growth than did birds from private owners. The frequency of ocular bacterial growth and types of bacteria isolated were similar to studies from dogs and cats.