Josué Díaz-Delgado

Endocarditis Associated with Wohlfahrtiimonas chitiniclastica in a Short-beaked Common Dolphin (Delphinus delphis)

Abstract Wohlfahrtiimonas chitiniclastica is a rare cause of fatal septicemia in humans, and recently reported in a white-tailed deer (Odocoileus virginianus). We describe fatal septicemia associated with W. chitiniclastica in a short-beaked common dolphin (Delphinus delphis) with fibrinosuppurative and necrotizing pulmonic, aortic, and mitral valve endocarditis.

Herpes virus infection associated with interstitial nephritis in a beaked whale (Mesoplodon densirostris)

BackgroundThe capacity for herpesvirus to cause disease in cetaceans is unclear and may be varied depending on the different conditions of individuals and between different species. Kidney pathology and intralesional virus-associated infection have been rarely reported in cetaceans.ResultOn April 2004, an old adult male Blainville’s beaked whale (Mesoplodon densirostris) 420 cm long with a poor body condition was stranded on Tenerife Island. During necropsy, no gross lesions were observed in the kidneys. However, membranous glomerulonephritis, multifocal interstitial lymphoplasmacytic nephritis and acute multifocal necrotizing tubulointerstitial nephritis with intranuclear inclusion bodies was diagnosed by histological analysis. Tissue samples were submitted for bacteriological analysis and molecular viral screening.ConclusionA novel alpha herpesvirus associated with interstitial nephritis was identified in an old adult male Blainvilles beaked whale (M. densirostris) with a poor body condition stranded in the Canary Islands. This report suggests that identification of herpesvirus infection could be used as a differential diagnosis for interstitial nephritis in cetaceans.

Primary Uterine T-cell Lymphoma with Metastasis in an Atlantic Spotted Dolphin (Stenella frontalis), Canary Islands, Spain

Abstract We describe gross, histopathologic, and immunonocytologic features of a primary uterine T-cell lymphoma with multiple metastases in an adult female Atlantic spotted dolphin (Stenella frontalis). Neoplastic T-cell lymphocytes (CD3+) partially effaced the uterus, ovaries, mesosalpinx, and urinary bladder and variably infiltrated abdominal and thoracic organs. Herpesvirus and morbillivirus PCR were negative.

Citrobacter freundii Septicemia in a Stranded Newborn Cuvier's Beaked Whale (Ziphius cavirostris)

Citrobacterfreundii, a gram-negative enterobacterium, may cause fatal septicemia in humans and animals. Its potential pathogenic role in cetaceans (bottlenose dolphins and beluga whales) has been hypothesized. Here we describe fatal C. freundii septicemia in a stranded newborn Cuvier’s beaked whale (Ziphius cavirostris).

Outbreak of Yellow Fever among Nonhuman Primates, Espirito Santo, Brazil, 2017

In January 2017, a yellow fever outbreak occurred in Espirito Santo, Brazil, where human immunization coverage is low. Histologic, immunohistologic, and PCR examinations were performed for 22 deceased nonhuman New World primates; typical yellow fever features were found in 21. Diagnosis in nonhuman primates prompted early public health response.

HERPESVIRUS-ASSOCIATED GENITAL LESIONS IN A STRANDED STRIPED DOLPHIN (STENELLA COERULEOALBA) IN THE CANARY ISLANDS, SPAIN

Abstract An adult male striped dolphin (Stenella coeruleoalba) stranded alive at Arico, Tenerife, Canary Islands, Spain. The dolphin died shortly after stranding, and a complete postmortem examination was performed. The most remarkable gross findings were two fleshy masses of approximately 1 cm diameter, near the tip of the penis. These masses were composed of hyperplastic epithelial cells with pigmentary incontinence. Ballooning degeneration and margination of chromatin was observed within the stratum corneum of the epidermis. A universal nested PCR assay that amplifies a conserved region within the polymerase gene of Herpesviridae was positive. The sequenced product was most closely related to a gammaherpesvirus that shared nucleotide identities of 93% with penile lesions from Atlantic and Mediterranean bottlenose dolphins (Tursiops truncatus). This similarity supports the hypothesis of sexual transmission between species.

Histopathological Muscle Findings May Be Essential for a Definitive Diagnosis of Suspected Sharp Trauma Associated with Ship Strikes in Stranded Cetaceans

Ship strikes are a major issue for the conservation of may cetacean species. Certain gross and microscopic criteria have been previously reported for establishing a diagnosis of death due to ship strikes in these animals. However, some ship-strike injuries may be masked by advanced carcass decomposition and may be undetectable due to restricted access to the animals. In this report we describe histopathological muscular findings in 13 cetaceans with sharp trauma from ship strikes as the cause of death. Skeletal muscle samples were taken from the incision site and from the main locomotor muscle, the longissimus dorsi, in areas not directly affected by the sharp injury. The microscopic findings in tissues from both sites mainly consisted of haemorrhages; oedema; flocculent, granular or/and hyalinised segmentary degeneration; contraction band necrosis; and discoid degeneration or fragmentation of myofibres. We propose that skeletal muscle histopathology provides evidence of ante-mortem injuries even if the sample was taken elsewhere in the carcass and not only within or adjacent to the sharp trauma site and despite the advanced decomposition of some of the carcasses. This method helps to establish the diagnosis of ship strike as the cause of death.

Verminous Arteritis Due to Crassicauda sp. in Cuvier’s Beaked Whales (Ziphius Cavirostris)

The vascular system of Cuvier’s beaked whales (CBW) (Ziphius cavirostris; family Ziphiidae), an extremely deep, prolonged-diving cetacean, is increasingly receiving anatomic and physiologic study due to possible anthropogenic interactions; however, vascular pathology rarely has been reported in this species. Thirteen CBW stranded in the Canary Islands from June 2008 to June 2014 were autopsied. A careful dissection of the thoracic and abdominal vasculature was performed on these animals. All had moderate to severe and extensive chronic fibrosing arteritis with aneurysms, hemorrhages, and thrombosis primarily involving the mesenteric and gastroepiploic arteries and the thoracic and abdominal aorta. Microscopically, the lesions varied from subacute subintimal hemorrhages and severe neutrophilic, eosinophilic, and histiocytic dissecting arteritis with intralesional nematode larvae to marked, chronic, fibrosing arteritis with thickening and distortion of the vascular wall with calcification and occasional cartilage metaplasia. In addition, adult nematodes in renal arteries and veins, renal parenchyma and/or ureter were identified morphologically as Crassicauda sp. Nucleic acid sequenced from renal nematodes from 2 animals yielded closest nucleotide identity to C. magna. The pathogenesis is proposed to involve a host response to larval migration from the intestine to the kidney through the mesenteric arteries, abdominal aorta, and renal arteries. Severe consequences for such lesions are possible and could vary from reduced vascular compliance to chronic renal disease and predisposition to the development of disseminated intravascular coagulation and multiorgan failure. Severe chronic arteritis in CBW is associated with renal parasitism by Crassicauda spp.

Deadly acute Decompression Sickness in Risso’s dolphins

Diving air-breathing vertebrates have long been considered protected against decompression sickness (DCS) through anatomical, physiological, and behavioural adaptations. However, an acute systemic gas and fat embolic syndrome similar to DCS in human divers was described in beaked whales that stranded in temporal and spatial association with military exercises involving high-powered sonar. More recently, DCS has been diagnosed in bycaught sea turtles. Both cases were linked to human activities. Two Risso’s dolphin (Grampus griseus) out of 493 necropsied cetaceans stranded in the Canary Islands in a 16-year period (2000–2015), had a severe acute decompression sickness supported by pathological findings and gas analysis. Deadly systemic, inflammatory, infectious, or neoplastic diseases, ship collision, military sonar, fisheries interaction or other type of lethal inducing associated trauma were ruled out. Struggling with a squid during hunting is discussed as the most likely cause of DCS.

Fatal Erysipelothrix rhusiopathiae septicemia in two Atlantic dolphins (Stenella frontalis and Tursiops truncatus).

We describe gross, histopathologic, ultrastructural, immunohistochemical, and microbiologic features of acute septicemia by Erysipelothrix rhusiopathiae in an Atlantic spotted dolphin Stenella frontalis and an Atlantic bottlenose dolphin Tursiops truncatus. Generalized lymphadenomegaly and widespread hemorrhages were the most consistent macroscopic findings. Tricavitary effusion and icterus were noted in one individual. Histologically, all organs examined showed numerous variably sized bacillary bacterial emboli (Gram-positive; Ziehl-Neelsen-negative), typically associated with systemic congestion, edema, hemorrhages, and fibrinocellular thrombi. These bacteria were frequently intravascular, either extracellular or intramonocytic/macrophagic, and to a lesser extent, free within the interstitium of parenchymal organs. In both cases, microbiological analysis yielded E. rhusiopathiae. A primary anti-E. rhusiopathiae antibody created in mice from one of the strains isolated allowed positive immunohistochemical detection. Electron microscopy and dual immunohistochemistry with lysozyme and MAC387 antibodies confirmed the intramacrophagic location of the bacilli. E. rhusiopathiae, a known multispecies and zoonotic agent, should be considered as a potential etiologic agent in septicemia cases in free-ranging individuals of these dolphin species.