Outcomes of Birds of Prey with Surgical or Traumatic Wing Amputation: A Retrospective Study from 1995 to 2017.

Surgical amputation of a limb is often required to treat raptor orthopedic injuries at rehabilitation centers. In some cases, amputation is an alternative to euthanasia if the bird's welfare is deemed appropriate under human care. The outcome for raptors maintained in a captive setting following wing amputation is poorly documented. A retrospective study was conducted in a Canadian raptor rehabilitation facility to assess the outcomes and complications observed in captive and free-living raptors with partial or complete, surgical or traumatic amputations of the wing. Data from raptors admitted to the rehabilitation center from 1995 to 2017 were reviewed. Overall, 32 records were included in this retrospective study from 11 species of raptors with surgical or traumatic wing amputations. Survival times of the 23 birds with an amputated wing (median: 1070 days, range: 68 days to 13 years and 1 month) were significantly (P = .02) longer than the survival times of the 404 non-amputated birds (median: 696 days, range 37 days to 27 years and 3 months). Complications occurred in 13 of 30 birds (43%) during the recovery period, with 9 of 30 (30%) birds developing life-threatening complications. Maladaptation to captivity was the leading cause of euthanasia during this period. After placement in captivity, 3/23 (13%) birds developed complications related to the amputation site. Based on this study, we conclude that some birds can tolerate partial or complete wing amputation, but the decision to place a bird in a captive setting should encompass the bird's ability to cope with human interaction and the availability of an adapted and safe enclosure for the animal.

CLINICAL OBSERVATIONS OF BEE ENVENOMATION IN TOUCANS.

There are numerous reports on envenomation, even fatal, secondary to bee attacks in humans and other mammals. In birds, reports on those incidents are scarce and there are none regarding honeybee (Apis mellifera) stings in toucans. In the first case presented, an adult female red-breasted toucan (Ramphastos dicolorus) received at least five bee stings in the periophthalmic area. Within 5 h the bird was lethargic and dehydrated. The urates were yellowish. Three days later the bird showed a moderate anemia, but no changes in the leukocyte count, beyond an elevated heterophil: lymphocyte ratio. Blood chemistry showed hyperglycemia, hypoalbuminemia and elevated aspartate aminotransferase and creatine kinase. Alterations in electrolyte values were also noted. Fourteen days later bile acid elevation was observed. Hematocrit levels normalized after 2 wk. A second incident involved a breeding pair of toco toucans (Ramphastos toco). While the female toco toucan received 10 stings and showed mild clinical manifestations, the male toco toucan was more severely attacked, receiving 40 stings, and died overnight. Despite the relative gravity of the attack (in terms of number of stingers in relation to body weight) both surviving birds recovered in less than 2 wk. To the authors' knowledge, fatal bee envenomation in birds has been reported only in pigeons and macaws. The findings described in this report suggest that toucans are less sensitive to bee venom when compared with pigeons and may have higher tolerance to bee venom compared with mammals. Honeybee envenomation must be considered a potential threat when considering toucan husbandry in zoos and collections.

A RETROSPECTIVE STUDY OF FEMORAL FRACTURES IN WILD BIRDS OF PREY: 119 CASES.

A retrospective study was performed to describe patient and fracture characteristics, treatments, complications, and outcomes associated with femoral fractures in free-ranging birds of prey. Cases were identified from the electronic database and included raptors admitted with femoral fractures at the Bird of Prey Clinic of the Université de Montréal, from 1986 to 2018. In total, 119 individuals from 24 species, with 123 femoral fractures, were included in the study. Twenty-seven birds (23%) were declared dead upon arrival. Ninety-two birds (77%) were admitted alive; 80 with acute fractures and 12 with a fracture that had already healed. A conservative treatment (cage rest) was used to manage eight fractures. Surgical repair was attempted on 34 femoral fractures in 33 birds. An intramedullary pin alone was used in 28 cases (82%), and an external skeletal fixator-intramedullary pin tie-in fixator was used in 6 cases (18%). For surgically treated fractures, 19 healed (in 18 birds), 4 did not heal, and 11 birds died or were euthanized before healing could be achieved. Of the 23/34 fractures where the healing process could be assessed, healing rate for comminuted fractures (11/23) was 91% (10/11). Surgical complications occurred in 10 cases (including 7 cases of migration and loosening of the pin, and 1 case of osteomyelitis), leading to euthanasia in 4 cases. Out of the 21 birds with acute femoral fracture upon presentation that were released, 14 had received a surgical treatment and 7 had received a conservative treatment. Nine of the 21 released birds (43%) had at least one other fractured bone. The majority of deaths and euthanasia occurred within 2 wk after admission (51/59; 86%). Thirteen birds were euthanized primarily because of their femoral fracture. Thirteen birds died in treatment and 33 were deemed nonreleasable and euthanized because of a comorbidity not related to the femoral fracture.

Postmortem findings in Magellanic penguins (Spheniscus magellanicus) caught in a drift gillnet.

BACKGROUND: Penguin interaction with gillnets has been extensively reported in the Atlantic and Pacific Oceans, and is considered a major conservation threat. Among penguin species, Magellanic penguins (Spheniscus magellanicus) are currently considered of great concern, particularly in Brazil, where they are highly susceptible to gillnet bycatch. Nevertheless, information about drowning-associated microscopic findings in penguins is limited. RESULTS: We describe the anatomopathological findings of 20 Magellanic penguins that drowned after getting entangled in a drift gillnet while wintering along the Brazilian shelf and washed ashore still enmeshed in Santa Catarina, Brazil. All 20 birds (19 juveniles and 1 adult; 18 females and 2 males) were in good body condition. Major gross findings were abrasion, bruising, and local erythema and edema of the wings, multiorgan congestion, jugular vein engorgement, pulmonary edema and hemorrhage, splenomegaly and hepatomegaly, fluid in the trachea, serous bloody fluid in the lungs, gastrointestinal parasites (nematodes, cestodes and trematodes), and debris in the stomach. The most common histopathological findings were cerebral and pulmonary congestion, pulmonary edema, splenic histiocytosis, lymphoid splenic hyperplasia, acute splenitis, extramedullary hepatic hematopoiesis, and parasitic enteritis. Although unspecific, the observed multiorgan congestion and pulmonary edema are consistent with previous reports of drowning in birds and may be indicative of this process. CONCLUSIONS: Drowning may be a challenging diagnosis (e.g., carcass decomposition, predation), but must be considered as a differential in all beach-cast seabird postmortem examinations. To the authors' knowledge this is the largest anatomopathological study based on microscopic examination in drowned penguins.

Effects of Perching Surfaces and Foot Bandaging on Central Metatarsal Foot Pad Weight Loading of the Peregrine Falcon (Falco peregrinus).

Pododermatitis is prevalent in falcons and is characterized by inflammation and infection of the plantar aspect of the feet, particularly at the central metatarsal pad. Suboptimal perch design and increased weight loading on the plantar skin have been proposed as major risk factors for the development of pododermatitis. Prevention and treatment are challenging, but weight load reduction on the affected area of the foot is an accepted goal of initial treatment. To date, to our knowledge no studies have compared the performance of different bandage-perch surface combinations on weight redistribution away from the central metatarsal pad. An ex vivo factorial experiment was designed using the feet from a peregrine falcon cadaver to quantify weight load reduction on the central metatarsal pad with different combinations of perch surfaces (wood, neoprene, artificial turf) and bandages (none, interdigital, silicone shoe). Feet were attached to a digital force gauge mounted on a manual test stand for compression testing. Weight loading at the central metatarsal pad was measured using a small force sensor. Perch-surface combinations in randomized order were tested at 250 g, 500 g, and 1 kg with 9 replicates per foot. At 250 g, all combinations reduced measured metatarsal pad forces, but otherwise performed similarly. As compression forces increased, differences emerged with the shoe combinations performing better overall, followed by a group including the neoprene and artificial turf-interdigital bandage combinations, and a third group including the interdigital/wood and no bandage-artificial turf. All combinations performed better than control (no bandage on wood). This study may assist veterinarians in selecting appropriate perching surface/bandage combinations when treating falcons with pododermatitis.

Erosive Enteritis and Intestinal Obstructions Caused by Decomposed Granite in a Flock of Lesser Flamingos (Phoeniconaias minor).

Decomposed granite is a material commonly used in zoos as a base for flamingo exhibits. In 2012, the artificial turf over the decomposed granite in the Fort Worth Zoo flamingo exhibit was removed and pressure washed, the granite was replaced, and the turf was then restretched in place. Approximately 8 months later, 3 lesser flamingos (Phoeniconaias minor) showed signs of lethargy and hematochezia. Results of physical examination revealed poor body condition in all birds, with variable hematologic abnormalities, including anemia, hypoproteinemia, and electrolyte disturbances. Radiographs of birds showed large amounts of radiopaque material in the ventriculus and dilated intestinal loops. Two birds died either during treatment or surgery, and 1 bird was euthanatized. Postmortem examination of all 3 birds revealed large amounts of fine, granite-like material in the ventriculus and intestines, severe congestion of intestinal mucosa, and obstruction of intestinal lumen by caseous plugs surrounded by fecal material. Microscopic evaluation of the material removed from the ventriculus showed birefringent crystals that corresponded to microscopic silica grains, consistent with the decomposed granite from the exhibit. Histologic examination of tissues showed marked chronic erosive colitis, mild erosive proventriculitis, and lesions in the muscular layer of the ventriculus. Subsequently, 82 remaining flamingos in the flock were radiographed. Results showed the same material in the ventriculus of most birds, but no intestinal obstructions were identified. Different treatment techniques were attempted unsuccessfully to remove the material from the flamingos that had the largest amount of decomposed granite in their gastrointestinal tracts. Ultimately, all birds were treated with oral gastrointestinal protectants, adsorbents, laxatives, and lubricants, along with antibiotics administered in drinking water. No further mortalities occurred once medical treatments were implemented.

Blind free-living kiwi offer a unique window into the ecology and evolution of vertebrate vision.

The first report of multiple, blind, wild birds in good health suggests vision is not necessary for the survival of kiwi.

REVIEW OF MORTALITY AND EFFECTIVENESS OF NEONATAL TREATMENT IN CAPTIVE ATTWATER'S PRAIRIE CHICKENS ( TYMPANUCHUS CUPIDO ATTWATERI).

A retrospective study of mortality and neonatal treatment for 975 Attwater's prairie chickens ( Tympanuchus cupido attwateri) was conducted from 2009-2015. Gross necropsy, histopathology, and medical records for chicks less than 8 wk of age at the Houston Zoo were reviewed and summarized. The total mortality rate was 36% ( n = 352). Yolk sac infection was the most common cause of death (21%; n = 73) followed by maladaptation (19%; n = 68), musculoskeletal abnormalities (19%; n = 66), necrotic enteritis (13%; n = 44), and mucoid enteritis (11%; n = 39). Gavage feeding of a highly digestible formula was associated with a higher proportion of necrotic enteritis and a reduced occurrence of both mucoid enteritis and maladaptation. Meloxicam administration had a significantly reduced incidence of mucoid enteritis. Survival past 10 days of age, prevention of neonatal bacterial infection, and supportive treatment with meloxicam are important factors to increase chick survival and improve captive breeding success for Attwater's prairie chickens. Gavage feeding of a diet low in digestible carbohydrates has the potential for reducing disease due to necrotic enteritis in this species.

RETROSPECTIVE STUDY OF MORTALITY IN CAPTIVE STRUTHIONIFORMES IN A FRENCH ZOO (1974-2015).

The husbandry and medical records, and necropsy reports, of 1,002 captive Struthioniformes that died at the Réserve Africaine de Sigean (France) from 1974 to 2015 were examined. The goal of this study was to determine the most common causes of mortality in ostriches ( Struthio camelus), emus ( Dromaius novaehollandiae), and American rheas ( Rhea americana), in order to highlight common causes of mortality, as well as the influence of age, gender, and rearing methods on mortality. The most prevalent cause of mortality was pathology of digestive origin in the neonates of all three species, especially yolk-sac infections, which accounted for 41% of all deaths in this captive neonate population and was especially prevalent in hand-reared neonates. Other causes included musculoskeletal disorders in emus (particularly hand-reared) and rheas; trauma in neonate ostriches, mainly due to crushing by parents; leg deformities in emu chicks and juveniles; general sepsis in hand-reared ratite chicks due to a chlamydiosis outbreaks (1989-1990); trauma by conspecifics in subadult ostriches and emus; stress myopathy in subadult rheas, particularly after introduction to a new enclosure; evisceration inflicted by herbivorous enclosure mates on adult male ostriches; fatal peritonitis following salpingitis in adult female ostriches; and death associated with ocular disorder in adult male emus. Although this study was conducted at one institution, and its results reflect this zoo's management and zootechnical practices, its findings could well have implications for management practices involving other captive Struthioniforme populations.

IRON STORAGE DISEASE IN AFRICAN GREY PARROTS ( PSITTACUS ERITHACUS) EXPOSED TO A CARNIVOROUS DIET.

Within a 2-wk period, three African grey parrots ( Psittacus erithacus) presented for emergency treatment. All three parrots had depressed behavior, an inability to fly, and significant weight loss. Plasma chemistry abnormalities included severe hypoproteinemia and elevated liver enzymes in all parrots. Two of the parrots died, and histologic examination with hematoxylin and eosin and Prussian blue stains revealed severe hepatic iron storage. Quantitative analysis confirmed high hepatic iron concentrations. Iron accumulation was attributed to ingestion of a carnivorous bird diet or selectively eating too much fruit and vegetables high in ascorbic acid. Management entailed husbandry changes including switching the remaining parrots to a low-iron diet. Psittacine species exposed to carnivorous bird diets are at risk of developing iron storage disease.

ANALYSIS OF HISTORICAL MEDICAL RECORDS OF CALIFORNIA CONDORS ( GYMNOGYPS CALIFORNIANUS) ADMITTED FOR LEAD EXPOSURE TO THE LOS ANGELES ZOO AND BOTANICAL GARDENS BETWEEN 1997 AND 2012: A CASE SERIES STUDY.

Lead toxicosis remains the primary cause of death in wild populations of California condors ( Gymnogyps californianus). Many condors require medical intervention with lead chelation therapy, among other conservation measures, to survive in the wild. An analysis of historical medical records of California condors admitted for lead exposure to the Los Angeles Zoo and Botanical Gardens (LA Zoo) between 1997 and 2012 was performed to investigate clinical presentation, radiographic findings, and treatment along with the potential impact of these factors on recovery and successful release back into the wild. Of 100 individual condors presented to the LA Zoo for suspected lead toxicosis during this period, 84 condors had records for initial laboratory blood lead levels. For these 84 condors (40 [47.6%] females and 44 [52.4%] males), 277 initial laboratory blood lead levels in total were recorded because of repeated admissions. Thirty-two (38%) condors were admitted once to the zoo and 62% were admitted two or more times. Clinical signs were not observed in 87.5% of the condors admitted with median blood lead concentrations of 26 µg/dl. Of the radiographs taken on initial presentation, 65% did not show evidence of gastrointestinal metallic foreign bodies. Various treatments protocols with edetatum calcium disodium, dimercaptosuccinic acid, and lactated Ringer's solution were documented in the medical records. Of the 277 admissions, 154 admissions had a recorded outcome posttreatment of which 140 (91%) admissions were released back to the wild. This study contributes to a better understanding of how intervention and therapeutic approaches have been essential for the recovery, release, and sustainability of these birds as a wild population. Consistency in data collection of California condors admitted for diagnosis and treatment of lead toxicosis is needed to better assess the impacts of medical interventions.

A Retrospective Study of Horner Syndrome in Australian Wild Birds, 2010-2016.

Horner syndrome was identified in 25 of 30 777 avian admissions to Currumbin Wildlife Hospital during 2010-2016. Unilateral ptosis and erection of facial feathers were distinct findings on physical examination and consistent across 9 species. Affected birds were biased toward adults (64%) suffering traumatic injuries (88%). Concurrent injuries requiring treatment were present in 38% of cases, and 76% had additional neurologic deficits. Prognosis for release was poor, with an overall success rate of 32%. Resolution of clinical signs increased to 44% with higher doses of meloxicam and required an average hospitalization of 22 days (range, 3-78 days). Further investigation of the underlying causes of Horner syndrome in birds to provide treatment and prognostic guidelines is warranted.

Trauma-Induced Uveitis and Free Air in the Anterior Chamber of Three Eastern Screech Owls (Megascops asio).

Unusual ocular abnormalities were documented in 3 wild eastern screech owls (Megascops asio) presented to a wildlife rehabilitation hospital after vehicular strike-induced trauma to the head. All 3 had anterior uveitis and free air bubbles in the anterior chamber, but none of the cases had any discernable corneal damage, either grossly or with fluorescein stain technique. Perforation of the globe at the level of the scleral ossicle was considered a possible cause. All 3 cases recovered with standard treatment for anterior uveitis, and the free air was absorbed within 10-14 days and did not appear to cause any lingering complications. The owls were later released back into the wild after demonstrating the ability to navigate obstacles in a flight cage and capture live prey.

A description of the gross pathology of drowning and other causes of mortality in seabirds.

BACKGROUND: Mortality of seabirds due to anthropogenic causes, especially entrapment in fishing gear, is a matter of increasing international concern. This study aimed at characterising the gross pathology of seabirds that drowned in fishing nets and comparing it with that in other common causes of mortality. RESULTS: Post-mortem examinations were performed on 103 common guillemots, 32 razorbills, 37 shags and 5 great northern divers found stranded in Cornwall during 1981-2016. Pathology in birds that died in confirmed incidents of drowning in fishing nets (n = 95) was compared with that in cases of suspected drowning (n = 6), oil (n = 53) and polyisobutylene (PIB) (n = 3) pollution, adverse weather (n = 6) and stranding of unknown cause (14). The majority of drowned birds were in good nutritional state, freshly dead and approximately 50% had freshly ingested fish in their proximal gut. Principle lesions were: gross distention of the heart and major veins with dark blood, intensely congested, swollen and oedematous lungs which released white frothy fluid when excised, watery fluid in the air sacs that ranged from clear to deep red depending on state of carcase preservation. PIB-affected birds were in good nutritional state; their pathology was largely consistent with that in confirmed drowning cases; it is likely that drowning was the ultimate cause of death. Birds affected by oil, adverse weather or that stranded due to unknown cause were all in poor or emaciated condition, the mean body mass of the guillemots and razorbills being, respectively, 53 and 57% of those that drowned. They had little or no food in their alimentary tracts and many showed evidence of enteric inflammation, haemorrhage and ulceration. None had fluid in their air sacs and none showed significant cardio-respiratory system lesions. CONCLUSIONS: Drowned birds consistently showed a distinctive set of gross pathological lesions. When combined with contemporaneous observations, the pathology may be sufficient to permit a diagnosis of drowning, especially where a batch of freshly dead birds are examined. The observations in this study are likely to be of value when investigating stranding incidents, particularly where it is suspected that legislation aimed at protecting seabirds is not being complied with.

PRESUMPTIVE PIT VIPER ENVENOMATION IN PSITTACINES IN A BRAZILIAN ZOO.

Snake bites represent a serious public health risk in many regions of the globe, especially in tropical areas. Clinical signs and postmortem changes are well described in human and other mammalian species. However, detailed case reports about venomous snake attacks in avian species are limited. This report describes presumptive fatal envenomations in three psittacines caused by pit vipers in a Brazilian zoo. In one case, a Brazilian lancehead (Bothrops moojeni) was captured in the aviary. In all three cases the dermis around the suspected snake bite area exhibited hemorrhages and edema. Histologically, degeneration and necrosis of subcutaneous musculature were observed. Lung, heart, and kidneys displayed focal hemorrhages. The local changes are similar to those described for mammalian patients including humans. However, except for the parenchymatous hemorrhages, additional external and internal gross and histopathological lesions were missing. After ruling out other causes, such as aggression and dicoumarinic intoxication, the presumptive diagnosis of snake envenomation was made. The smaller size and variabilities of pathophysiological effects of the venom in parrots might explain the different lesion patterns observed, compared with mammals. Possibly, the birds may have reacted differently to envenomation by pit vipers and died before the venom could cause macroscopic and histological changes often observed in mammals.

DECLINE OF GAME BIRDS (PHASIANUS COLCHICUS AND PERDIX PERDIX) IN BAVARIA: A SURVEY ON PATHOGENIC BACTERIA, PARASITES, PESTICIDE RESIDUES, AND INFLUENCE OF SET-ASIDE LAND AND MAIZE CULTIVATION.

Due to a Europe-wide decline of grey partridge ( Perdix perdix ) and pheasant ( Phasianus colchicus ) populations, this study was conducted focusing on the county of Bavaria, south Germany. The aim was to assess the health status of game birds and identify possible causes of decline. For this purpose 203 pheasants and 11 partridges were examined during the 2011 hunting season. Pathologic examinations were conducted including examinations for parasites and bacteria. Due to public health significance, a screening for Salmonella sp., as well as real-time polymerase chain reaction examinations for Campylobacter sp. and Mycobacterium avium ssp. avium, were done. Because pesticides and land-usage can possibly influence bird numbers, the birds were screened for environmental toxin residues, including neonicotinoid insecticides, and land-usage data were correlated with the hunting bags. The result was a very-strong positive correlation of set-aside areas and a less-strong negative correlation of maize cultivation acreage. More than 90% of the birds had a good health status; only individuals showed pathologic alterations. For example, avian tuberculosis was found in two pheasants and a severe capillariosis in two partridges. A possible role of female reproductive disorders has to be confirmed in further investigations. In conclusion, results suggest the decrease of set-aside areas could be a possible reason for decline.

Tracheal Resection in a Secretary Bird ( Sagittarius serpentarius) with Granulomatous, Foreign-body Induced Tracheitis.

A 24-year-old female secretary bird ( Sagittarius serpentarius) was presented with acute, mild dyspnea occurring only during feeding times. Despite initial conservative therapy consisting of antibiotics and antifungal, antiparasitic, and anti-inflammatory drugs, the dyspnea worsened progressively, resulting in severe respiratory distress. Radiographs of the trachea suggested stenosis in the caudal one-third of the trachea. Tracheal endoscopy revealed an obstruction of approximately 90% of the tracheal lumen, in addition to mild suspected aspergillosis of the air sacs. Tracheal resection and anastomosis were performed, during which 1.5 cm of abnormal trachea was removed. Histopathologic examination showed severe granulomatous tracheitis, most likely induced by foreign body material. Respiratory signs resolved immediately postoperatively. Antibiotic and anti-inflammatory therapy continued for another 7 days and the bird was treated with antifungals for a total of 45 days. The bird recovered uneventfully. We encourage tracheal resection and anastomosis for severe tracheal stenosis even in aged, large birds of prey that are managed in large aviaries.

Multimodal Drug Therapy and Physical Rehabilitation in the Successful Treatment of Capture Myopathy in a Lesser Flamingo (Phoeniconaias minor).

A wild-caught lesser flamingo (Phoeniconaias minor) from the Fort Worth Zoo (Fort Worth, TX, USA) presented with moderate lameness that progressed to the inability to stand 2 days after restraint and handling. Results of blood tests showed severely elevated creatine phosphokinase (CPK) and aspartate aminotransferase (AST) activities, confirming suspected capture myopathy. Intensive supportive therapy, consisting of intravenous fluids and muscle relaxants, along with physical rehabilitation therapy, nutritional support, and anxiolytics, were instituted to aid in relaxation and muscle regeneration. After 2 weeks of intensive therapy, the bird showed substantial improvement and could remain standing throughout the day after being assisted to a standing position. By day 23, the bird was able to stand independently and walk completely unassisted, with no discernible lameness. The bird has subsequently remained healthy since it was returned to the flock approximately 27 days after it was first presented for treatment. Although anecdotal communications of successful treatment of this condition in flamingos exist, this is the first report, to our knowledge, that describes in detail the successful treatment of capture myopathy in any flamingo species. Success in this case is attributed to the combination of early fluid and drug therapy, intensive physical rehabilitation therapy, and anxiolytics to counteract the hyperexcitable nature of this wild-caught bird.

Lesions associated with drowning in bycaught penguins.

Fisheries bycatch, the incidental mortality that occurs as a result of entanglement in fishing gear, is an important conservation threat to penguins and other seabirds. Identification of entanglement and drowning in beach-cast carcasses of seabirds remains a challenge, as it is still unclear what lesions are to be expected in a bycaught seabird. We necropsied 2 Magellanic penguins Spheniscus magellanicus that were entangled and drowned in gillnets. Marked distension of the lungs with foamy red fluid and marked oedema of the dorsal visceral pleura were prominent lesions consistent with those described in cases of 'wet drowning' in humans. On the other hand, the air sacs contained very small quantities of liquid, suggesting that absence of water in the air sacs might not be a reliable sign to exclude drowning. Other relevant findings included cutaneous lacerations and bruising in one bird and cervical and pectoral rhabdomyolysis in both birds. While cutaneous or subcutaneous hematomas may be an indication of bycatch, especially if linear or cross-linear patterns consistent with fishing nets are present, these lesions might not always be discernible and their absence does not suffice to exclude the possibility of entanglement in fishing nets. Additionally, our findings suggest that the histological examination of skeletal muscles, particularly of the neck, may provide additional clues to corroborate the diagnosis of drowning in penguins.

EVALUATION OF POTENTIAL RISK FACTORS ASSOCIATED WITH CATARACT IN CAPTIVE MACARONI (EUDYPTES CHRYSOLOPHUS) AND ROCKHOPPER PENGUINS (EUDYPTES CHRYSOCOME).

Complete ophthalmic examinations were performed on 160 Macaroni penguins ( Eudyptes chrysolophus ) and 90 Rockhopper penguins ( Eudyptes chrysocome ) at eight North American zoological institutions. Cataract prevalence in the Macaroni population was 46.5% (n = 74) of penguins and 42.3% (135/319) of eyes. Cataract prevalence in the Rockhopper population was 45.5% (n = 40) of penguins and 40.6% (73/180) of eyes. The mean age of Macaroni penguins without ocular disease was 7.4 ± 5.8 yr, while that of Rockhoppers was 9.8 ± 6.4 yr. Risk factors for cataract were examined through husbandry surveys completed by each institution and by evaluation of light intensity and ultraviolet (UV) light measurements acquired in each penguin exhibit. Risk factors associated with cataract in Macaroni penguins included age, dietary smelt, hand-feeding, and fluorescent exhibit lighting. Risk factors associated with cataract in Rockhopper penguins included age, dietary capelin, increasing population density, and increasing length of minimum photoperiod. Factors associated with decreased odds of cataract in Macaroni penguins included saltwater pool, monitoring of water quality for salinity, pH, and alkalinity; use of water additives; presence of pool filtration and sterilization systems; use of metal halide lightbulbs; increasing light intensity; and UV spectrum lighting. Factors associated with decreased odds of cataract in Rockhoppers included dietary herring and krill, increasing exhibit land area, pool temperature monitoring, increasing maximum photoperiod, and increasing minimum UV light.