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Birds are among the most visually proficient group of animals on the planet; however, their inability to visualize and discriminate translucent glass structures results in an extreme number of deaths worldwide from high-speed collisions. Despite reports of avian glass collisions in North America, only a few studies have been developed to understand this problem in South America, and none evaluated radiographic and postmortem findings. One hundred cadavers were examined radiographically and postmortem, and data from 186 collision reports were analyzed for seasonality (website and manual reports and cadavers). A total of 34 different species of birds within 22 families were evaluated for this study, with the rufous-bellied thrush (Turdus rufiventris; n = 12), eared dove (Zenaida auriculata; n = 12), and ruddy ground dove (Columbina talpacoti; n = 10) being the most common species. Only 6 (27.7%) migratory species were reported: Sick's swift (Chaetura meridionalis), small-billed elaenia (Elaenia parvirostris), Black Jacobin (Florisuga fusca), Great kiskadee (Pitangus sulphuratus), Double-collared seedeater (Sporophila caerulescens), and Creamy-bellied thrush (Turdus amaurochalinus). Males (51) were more frequently reported than females (5), and 50.1% of the males had active gonads. Sex was unable to be determined in 44 birds. The most common radiographic lesion, noted in 16 of 82 (19.5%) animals, was loss of coelomic definition, suggestive of hemorrhage. Prevalent postmortem findings included skull hemorrhages (58/75, 77.3%) and encephalic contusions (47/73, 64.4%), followed by coelomic hemorrhages (33/81, 40.7%). Most of the window collisions (61/186, 32.8%) occurred during spring, the most common breeding season of avian species in Brazil. Cranioencephalic trauma was identified as the primary cause of mortality associated with birds flying into glass windows. Migration does not appear to be the main predisposing factor for window collisions by birds in Brazil. Increased activity and aggression related to breeding season, especially in males, may be a more important predisposing factor for window collision accidents.

Background The pecten oculi is a vascular and pigmented structure localized within the posterior segment of all avian eyes. Its primary function is not fully understood yet. Objective As ultrasonography (US) is a useful imaging modality for evaluation of the pecten oculi, the objective of this study was to investigate the utility of an intravenous contrast solution of sulfur hexafluoride (SF6) microbubbles as a means of enhancing visualization of the pecten oculi in normal birds. Animals studied Ten adult individuals of the following avian species were evaluated: 1 roadside hawk (Rupornis magnirostris), 1 stygian owl (Asio stygius), 2 striped owls (Asio clamator), 2 burrowing owls (Athene cunicularia), 2 ring-necked parakeet (Psittacula krameri), and 2 domestic chickens (Gallus gallus domesticus). Procedure(s) After baseline ocular sonograms were obtained in sedated animals, 4.5 μg/kg of a contrast solution containing SF6 microbubbles was administered intravenously and US of the right eye was immediately performed. US was continued during injection to provide real-time imaging of the pecten oculi during vascular perfusion of contrast material. Results Within 2-3 seconds following intravenous contrast administration, microbubbles reached the pecten oculi of all birds investigated and provided significant ultrasonographic contrast enhancement. Conclusions SF6 microbubble contrast ultrasonography in birds is a safe and easy procedure that provides increased contrast and enhanced visualization of the pecten oculi. Future use may enable further discovery of its physiologic functions and aid in the development of therapeutic plans for avian intraocular disease.

Problems with indoor husbandry and immunological challenges are some of the stressors that broilers may face which can affect production. Infectious diseases can compound the effects of excessive concentrations of ammonia causing respiratory and ocular inflammation and increased lacrimal production in broiler chickens. The objectives of this investigation were to establish normal values of tear production in chicks and compare the practicality of the different methods. Palpebral fissure length (PFL) and tear production were evaluated in Cobb 500 chicks at 5 d old and then at 5 d of age by the following methods: modified Schirmer's test I (mSTT1), phenol red cotton thread tear test (PRCTTT), and standardized endodontic absorbent paper point test (EAPPTT). Ten chicks at the age of 5 and 42 d were evaluated for each method. In addition, at 42 d, when the palpebral fissure permitted, a regular-sized Schirmer tear test I (STT1) was performed in another group of 10 chickens. Overall, PFL and the secretion of the aqueous phase of the tear film increased with age. Mean mSTT1 results were 5.00 ± 1.83 mm and 10.45 ± 2.58 mm for 5- and 42-d-old chicks, respectively. Mean PRCTTT results were 12.37 ± 1.80 mm and 25.58 ± 4.8 mm for 5- and 42-d-old chicks, respectively. Mean EAPPTT results were 7.13 ± 0.72 mm and 12.03 ± 0.92 mm for 5- and 42-d-old chicks, respectively. Mean STT1 for 42-d-old chicks was 11.40 ± 2.60 mm. Results obtained with endodontic paper points showed the lowest coefficient of variation and investigators found the test easier to perform. These values reported for broilers at different ages may be applied in poultry ophthalmology to help the diagnosis of lacrimal production disorders and to detect early disease symptoms that could cause economic losses in poultry production.