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Between 2019 and 2021, 21 bottlenose dolphins were found stranded dead along the Ligurian Pelagos Sanctuary coast (Italy). For 11 animals, out of a total of 14 recovered, the cause of death was classified as natural, anthropic, or not determined based on gross and histological pathology and ancillary testing. Hexachlorobenzene (HCB), dichlorodiphenyltrichloroethanes (DDTs), and polychlorinated biphenyls (PCBs) were examined in their blubber, and results were discussed according to their toxicological properties. All specimens showed the following trend: PCBs > DDTs >> HCB, and the levels of cancerogenic, mutagenic, and teratogenic organochlorine compounds (T-OCs) were >50% of total OCs. Immunosuppressant organochlorine compound (IS-OC) levels in 10 out of 11 animals were above 50% of the total OCs. PCB levels always exceeded the threshold of 17 mg/kg lipid weight for PCB-induced adverse health effects. The results suggest that bottlenose dolphins living in the Pelagos Sanctuary undergo a high level of exposure to pathogens and OCs, betraying the designation of the Cetacean Sanctuary and, consequently, of a region created for their conservation. Immune dysfunction and infectious disease susceptibility appear to be highly connected with high levels of OC xenobiotics. These data are useful to understand health and mortality trends in cetacean populations, as well as for developing policies for cetacean conservation and management in this important protected area of the Mediterranean. [ABSTRACT FROM AUTHOR]

A Mediterranean monk seal (Monachus monachus) pup from the southern Adriatic coast of Italy showed cetacean morbillivirus (CeMV) and disseminated Toxoplasma gondii co-infection, which probably resulted from CeMV-induced immunosuppression. These findings are of concern for the conservation of this critically endangered species. [ABSTRACT FROM AUTHOR]

Between 2007 and 2014, 83 cetaceans were found stranded along the Ligurian coast of Italy, in the Pelagos Sanctuary, the largest marine protected area in the Mediterranean basin. Forty-nine (59%) were submitted to complete or partial necropsy, depending on the conservation status of the carcass. Based on gross and histological pathology and ancillary testing, the cause of death was determined and categorized as anthropogenic or natural (i.e., nonanthropogenic) in origin for 33 animals (67%) and of undetermined origin in the remaining 16 (33%). Natural causes of death, accompanied by either poor or good nutritional status, were attributed to 29 animals (59%), whereas four (8%) were diagnosed with an anthropogenic cause of death, consisting of interaction with fishing activities. Infectious and noninfectious disease was the most common cause of death, involving 29 cetaceans (59%). These data are valuable for understanding health and mortality trends in cetacean populations and can provide information for establishing policies for cetacean conservation and management in such an important protected area of the Mediterranean basin. [ABSTRACT FROM AUTHOR]

Morbilliviruses are recognized as biological agents highly impacting the health and conservation status of free-ranging cetaceans worldwide, as clearly exemplified by the two Dolphin Morbillivirus (DMV) epidemics of 1990-1992 and 2006-2008 among Mediterranean striped dolphins (Stenella coeruleoalba). After these two epidemics, morbilliviral infection (MI) cases with peculiar neurobiological features were reported in striped dolphins stranded along the Spanish coastline. Affected cetaceans showed a subacute- to-chronic, non-suppurative encephalitis, with brain lesions strongly resembling those found in human "subacute sclerosing panencephalitis" and "old dog encephalitis". Brain was the only tissue in which morbilliviral antigen and/or genome could be detected. Beside a case of morbilliviral encephalitis in a striped dolphin's calf stranded in 2009, we observed 5 additional MI cases in 2 striped dolphins, 1 bottlenose dolphin (Tursiops truncatus) and 2 fin whales (Balaenoptera physalus), all stranded in 2011 along the Italian coastline. Noteworthy, 3 of these animals (2 striped dolphins and 1 bottlenose dolphin) showed immunohistochemical (IHC) and/or biomolecular (PCR) evidence of morbilliviral antigen and/or genome exclusively in their brain, with 1 striped dolphin and 1 bottlenose dolphin also exhibiting a non-suppurative encephalitis. Furthermore, simultaneous IHC and PCR evidence of a Toxoplasma gondii coinfection was obtained in 1 fin whale. The above results are consistent with those reported in striped dolphins after the two MI epidemics of 1990-92 and 2006-2008, with evidence of morbilliviral antigen and/or genome being found exclusively in the brain tissue from affected animals. [ABSTRACT FROM AUTHOR]

Abstract: This study reports the occurrence of Toxoplasma gondii in the brain of three striped dolphins (Stenella ceoruleoalba) found stranded on the Ligurian Sea coast of Italy between 2007 and 2008. These animals showed a severe, subacute to chronic, non-purulent, multifocal meningo-encephalitis, with the cerebral parenchyma of two dolphins harbouring protozoan cysts and zoites immunohistochemically linked to T. gondii. Molecular, phylogenetic and mutation scanning analyses showed the occurrence of Type II and of an atypical Type II T. gondii isolates in one and two dolphins, respectively. In spite of the different molecular patterns characterizing the above T. gondii genotypes, the brain lesions observed in the three animals showed common microscopic features, with no remarkable differences among them. The role of T. gondii in causing the meningo-encephalitis is herein discussed. [Copyright &y& Elsevier]