Images

Photomicrographs from a muskrat (Ondatra zibethicus) found dead in Ohio, USA. (A) Within the liver, there is a cluster of nematode eggs with light brown to eosinophilic bi-operculated shells (arrowheads) with radial striations (arrow) that contain eosinophilic flocculent material (asterisk). H&E stain.

Photograph and photomicrographs from a bottlenose dolphin (Tursiops truncatus) found dead in Florida, USA.  (A) On the right cranial cerebrum is a 3 x 2.5 cm area of hemorrhage and cavitation. (B) There is focal marked cerebral meningeal cavitation and hemorrhage, with fibrin accumulation, neutrophils, and triangular to ovoid trematode eggs (arrows).

Photographs from a Bald Eagle (Haliaeetus leucocephalus) that was found moribund and died in South Dakota, USA. (A) There is abundant liquid and clotted blood (*) in the coelomic cavity surrounding the heart (top), liver (middle), and within the coelomic adipose tissue (bottom). The liver is diffusely pale tan with rounded margins.

Photographs from an American Crow (Corvus brachyrhynchos) found dead in Ohio, USA. (A) The gastrointestinal tract is oriented with the ventriculus to the upper right. The small intestines are diffusely dilated and red-purple on the serosal aspect.

Photomicrographs from an American Crow (Corvus brachyrhynchos) found dead in Ohio, USA. (A) The small intestines contain necrotic material (N) with foci of mineral (arrow) within the lumen. The mucosa is multifocally effaced by hypereosinophilic cellular debris (necrosis) and inflammatory cells (*). H&E stain.

Photomicrographs from a Trumpeter Swan (Cygnus buccinator) found dead in Indiana, U.S.A. (A) Within the small intestine is an area of transmural necrosis (arrow) with abundant luminal necrotic debris and hemorrhage containing few trematode eggs (arrowhead), and an adjacent trematode (*).  H&E stain.  (B) Detail of A.

Photographs from a Trumpeter Swan (Cygnus buccinator) found dead in Indiana, U.S.A.  (A) The majority of the intestinal serosa is dark red. (B) The lumen contains gelatinous dark red material and many <1 mm diameter white structures (trematodes) (arrows). (C) On the serosal surface are two 2 to 5 mm discrete ulcers (arrow).

Photomicrographs with H&E stain from a Bald Eagle (Haliaeetus leucocephalus) found dead in Wisconsin, USA. (A) Hepatocytes contain one or more variably-sized intracytoplasmic round, clear vacuoles (arrowheads). (B) Bile ducts are plugged with bile (asterisk). (C) Multifocally in the brainstem, there are small perivascular hemorrhages (arrows).

Gosner stage 41 Green Frog (Lithobates clamitans) tadpole. (A) There are no apparent external abnormalities. (B)The liver and spleen are markedly pale and enlarged.

Liver from a Green Frog (Lithobates clamitans) tadpole. (A) Over 90% of the organ is infiltrated, effaced and replaced by protozoal spores (Perkinsea) admixed with necrotic debris. (B) Perkinsea spores are 4 to 6-µm in diameter spherical structures with thick, deep basophilic walls, and granular pale basophilic cytoplasm. H&E stain.

Photomicrographs from a European Starling (Sturnus vulgaris) that was euthanized in the District of Columbia, USA. (A) There is an area in the brain with abundant acute hemorrhage (H) surrounding blood vessels and in the neuropil. H&E stain.

Photomicrographs from a Northern Shoveler (Spatula clypeata) from Utah, USA. H&E stain. (A) The air sac epithelium is replaced by or covered with a thick layer of fibrin admixed with heterophils and fewer macrophages and eosinophilic and cellular necrotic debris (*).

Biological Sciences Laboratory Technician donning protective gear for SARS-CoV-2 testing in the NWHC Diagnostic Virology Laboratory.

Photomicrographs from an eastern gray squirrel (Sciurus carolinensis) found dead in Wisconsin, U.S.  (A) On low magnification, the cerebrum exhibits areas of hypercellularity (arrows). H&E stain.  (B) Detail of A: There is mild lymphoplasmacytic perivascular cuffing (arrowhead) and areas of gliosis (arrow) within the cerebrum.

Photographs and a radiograph from a Northern sea otter (Enhydra lutris kenyoni) from Oregon, U.S.A. (A) The deceased sea otter on a beach in Oregon, U.S.A.

Photographs from Wild Turkeys (Meleagris gallopavo) found dead in Wisconsin, USA.  (A) The liver contains many multifocal to coalescing bullseye-shaped foci of necrosis (arrows). The ventriculus (*) is labeled for orientation. (B) The paired ceca (*) are ectatic with thickened walls.

Photomicrographs from Wild Turkeys (Meleagris gallopavo) found dead in Wisconsin, USA.  (A) In the liver, hepatocytes were replaced by macrophages, lymphocytes, and plasma cells (lower left) with occasional multinucleated giant cells (arrows). H&E stain.  (B) The cecum contains a fibrinonecrotic membrane effacing the mucosa (arrow).

USGS scientists and partners applied hot water as a control method for invasive corallimorphs at Palmyra Atoll National Wildlife Refuge.

USGS scientists and partners applied a toothpaste-like compound mixed with sodium hydroxide as a control method for invasive corallimorphs at Palmyra Atoll National Wildlife Refuge.

Photographs from red crossbills (Loxia curvirostra; A, C) and American goldfinches (Spinus tristis; B, D) from Montana, U.S.A. (A) A large yellow/tan plaque (asterisk) is present on the mucosal surface of the crop. (B) White seed-like plaques (arrow) are present on the mucosal surface of the crop.

Photomicrographs from a California newt (Taricha torosa) found moribund in California, USA. (A) Necrosis of the tail tip with exposed vertebral bone (B), hyperplastic epithelial regrowth at the edges (arrowhead), moderate mixed leukocytes and dilated lymphatics (*), and a few osteoclasts remodeling the exposed bone (arrows). H&E stain 4X.