Pathology

  Ocular glioneuroma with medulloepitheliomatous differentiation in a goldfish (Carassius auratus)

Autori: MANDRIOLI L, SIRRI R, GUSTINELLI A, QUAGLIO F, SARLI G, CHIOCCHETTI R

Riferimenti: Journal of Veterinary Diagnostic Investigation (2014) 26(1): 167-172

Summary: An intraocular mass in the left eye causing chronic severe exophthalmia in an adult female goldfish (Carassius auratus) is described. The fish shared an aquarium with another goldfish found dead with gross and microscopic lesions consistent with mycobacteriosis. Histological examination of the left eye, histochemical (periodic acid–Schiff [PAS], Alcian blue, Ziehl–Neelsen) and immunohistochemical tests (glial fibrillary acidic protein, human neuronal protein, vimentin, and cytokeratin AE1/AE3) were carried out on the intraocular mass. Neoplastic cells forming an unencapsulated highly cellular proliferation partially covered by an intact corneal epithelium were stained with Alcian blue, which demonstrated an abundant hyaluronic acid–rich extracellular matrix. Multifocally, there were cyst-like dilatations bordered by neuroepithelial cells, which were PAS-positive. The complex neoplastic proliferation was composed of glial-like cells, neuronal-like cells (immunoreactive to glial fibrillary acidic protein and human neuronal protein, respectively) and neuroepithelium, which suggested a retinal origin.

Link: https://journals.sagepub.com/doi/10.1177/1040638713515218

  Disseminated mycobacteriosis in a stranded loggerhead sea turtle (Caretta caretta)

Autori: NARDINI G, FLORIO D, DI GIROLAMO N, GUSTINELLI A, QUAGLIO F, FIORENTINI L, LEOPARDI S, FIORAVANTI ML

Riferimenti: Journal of Zoo and Wildlife Medicine (2014) 45(2): 357–360.

Summary: A loggerhead sea turtle (Caretta caretta) was found stranded alive along the Adriatic coast close to Ancona, Italy, displaying obtundation, tachypnea, and increased respiratory effort. It died a few hours after admission, and a postmortem examination was immediately performed. Miliary yellowish nodules were evident in the liver, and a lower number in the heart, stomach, and gut wall. Hundreds of whitish nodules were scattered in the lungs, with the majority of the pulmonary parenchyma being replaced by the lesions. Histologically, all nodular lesions consisted of a small central area of necrosis with acid-fast bacilli surrounded by epithelioid cells, macrophages, and lymphocytes. Giant cells were found in the spleen and the liver. Kidneys, lungs, liver, spleen, brain, and skin lesions were inoculated aseptically onto general isolation media and selective isolation media for mycobacteria. The isolate showed a restriction pattern identical to Mycobacterium chelonae by polymerase chain reaction–restriction fragment length polymorphism. To the best of the authors' knowledge, this is the first description of a disseminated infection caused by a potentially pathogenic mycobacteria in a stranded, free-ranging loggerhead sea turtle. Veterinary staff and biologists who handle sea turtles with suspected mycobacterial disease should protect themselves appropriately.

Link: https://www.ncbi.nlm.nih.gov/pubmed/25000698

  Redfin perch juveniles, Perca fluviatilis L., are resistant to European viral haemorrhagic septicaemia virus and infectious haematopoietic necrosis virus delivered via immersion in experimental condition

Autori: PASCOLI F, BORGHESAN F, MANFRIN A, QUAGLIO F, GATTI F, TOFFAN A

Riferimenti: Journal of Fish Diseases (2015) 38: 589–594

Summary: In our study, the infection was performed with European strain of VHSV and IHNV, and very little or no mortality and clinical signs were detected in infected redfin perch, while Rainbow trout showed high mortality rates with evident clinical signs, such as exophthalmos and severe haemorrhages. Results of our study demonstrate the level of resistance of redfin perch to Italian strains of VHSV and IHNV under simulated natural conditions in our facilities.

Link: https://onlinelibrary.wiley.com/doi/full/10.1111/jfd.12272

  Nodular gill disease in farmed rainbow trout (Oncorhynchus mykiss) in Italy

Autori: QUAGLIO F, PEROLO A, BRONZATTI P, GUSTINELLI A, MENCONI V, CAVAZZA G, CAFFARA M, MANFRIN A, GALLO E, FIORAVANTI ML

Riferimenti: Journal of Fish Diseases (2016) 39:1139-1142

Summary: Nodular gill disease (NGD) is a serious parasitic condition associated with amoebic infection affecting farmed rainbow trout (Oncorhynchus mykiss) in several countries worldwide. Outbreaks of NGD have been recently observed in several rainbow trout farms in Italy, with clinical signs strongly indicative of respiratory distress and high mortality registered mainly during winter. From December 2013 to April 2015 a total of 494 rainbow trout were collected from 13 Italian farms and subjected to anatomo-pathological and histological exams. Gross gill lesions consisted in excessive mucus production, swelling, whitish nodules in the distal parts of filaments and presence of alternate discolored and congested areas. In 261 (52.8%) fish histology allowed to identify the presence of amoebae as showed also by the parasitological exam of fresh gill samples. Histological lesions, in presence of amoebae, consisted in strong hyperplasia of the gill epithelial cells producing extensive lamellar fusion with obliteration of interlamellar spaces. In more severe cases mucous cell hypertrophy, lamellar edema, necrosis and exfoliation of epithelial cells were observed. Among the epithelial cells, inflammatory infiltrate with numerous lymphocytes, macrophages and eosinophilic granule cells/mast cells was detected. Further analyses are in progress in order to identify the species of amoebae involved as causative agent of NGD in Italy.

Link: https://onlinelibrary.wiley.com/doi/full/10.1111/jfd.12446

  Squamous cell carcinoma in a wild European bullhead Cottus gobio

Autori: QUAGLIO F, ZAPPULLI V, POPPI L, CAPOVILLA P, CAPPARUCCI F, MARINO F

Riferimenti: Diseases of Aquatic Organisms (2015) 122: (1) 73-76

Summary: A pharyngeal tumor was found in a wild European bullhead. The tumor mass ap-peared underneath the operculum and was bilobed. The major neoplastic component showed diffuse epithelial squamous differentiation. Crossmonn's trichrome allowed identification of connective tissues whereas no neoplastic cells were stained. Periodic acid-Schiff was negative within the mass, and Giemsa did not show any further diagnostic significance. Immunohistochemistry showed diffuse positive cytoplasmic staining of the neoplastic population with an anti-human pancytokeratin antibody. Vimentin was negative and exclusively stained the stroma. On the basis of the morphological and immunohistochemical results, a squamous cell carcinoma was diagnosed. Link: https://www.researchgate.net/publication/308533748_Squamous_cell_carcinoma_in_a_wild_European_bullhead_Cottus_gobio

  Malattia nodulare branchiale, patologia emergente negli allevamenti italiani di trota iridea (Oncorhynchus mykiss)

Autori: PEROLO A, QUAGLIO F, BRONZATTI P

Riferimenti: Ittiopatologia (2016) 13: 5-33

Summary: Since 2012 there has been found an increased mortality in Rainbow Trout (Oncorhynchusmykiss) farming of the Trento province. The affected fish showed typical symptoms of the gill disease (flared operculae,increased mucus andanemia)reaching mortality rates approaching 60% during the winter months.Water analysis were carried out from the tanks of some Trentino trout farms to investigate the etiology of this disease. The results of physicochemical parameters obtained between February and April 2014 didn’t show correlations with the pathology. The bacteriological examinations from the gills were carried out to find mixobacterial infections. No correlations were found between the bacterium presence and gill disease.Histology exam showan intense proliferative reaction of gill tissue with fusion of secondary lamellae and, in the most severe cases, of filaments. These lesion were similar to those described in “”Amoebic Gill Disease” in marine salmon farming in Australia (Tasmania), North America (Canada and USA), Northern Europe(Ireland, France, Spain, Scotland and Norway), Southern America (Chile) and Africa (South Africa) and in “Nodular Gill Disease” in freshwater trout farming in Nord Europe (Denmark, Germany, Poland and Czech Republic) and Northern America (Canada and USA). Unicellular microorganism belonging to the amoeba order have been identified by microscopic examinations with histological Giemsa staining. Parasitological analysis conducted bycultured of fresh gill tissue permitted to reveal presence of replicating amoebae. Biomolecular studies to typing amoebic organism are required.The research continued until April 2015, quantifying the histological lesions and the degree of infestation ofthe parasite. Up to now, the researches show an evident correlation between the proliferative lesions and the number of amoebae present in the gill tissue.

Link: http://tesi.cab.unipd.it/49161/1/Perolo_Alberto.pdf

  Anisakiasi ittica: studio ecoparassitologico in diversi areali di pesca del Mar Adriatico centro-meridionale

Autori: COSTANTINI E, BOSCO C, GUSTINELLI A, CAFFARA M, MENCONI V, SCATURRO G, QUAGLIO F, GAVAUDAN S, CAPOZUCCA A, CICCARELLI C, BISCEGLIA D, PREARO M, FIORAVANTI ML

Riferimenti: Ittiopatologia (2016) 13: 35-56

Summary: Scopo primario del presente studio è stato quello di determinare la diffusione di larve di nematodi Anisakidae del genere Anisakis in specie ittiche, in primis alici e sardine, pescate in diversi areali del Mar Adriatico centro-meridionale, comparando i risultati con i dati disponibili per gli areali adriatici settentrionali e valutando le eventuali correlazioni con fattori di tipo ambientale ed ecologico. I risultati ottenuti nel corso di questo studio hanno mostrato, su 2.332 pesci esaminati in totale e rappresentati da diverse specie ittiche di interesse commerciale provenienti da areali di pesca del mar Adriatico centrale e meridionale (Ancona, S. Benedetto del Tronto, Manfredonia, Molfetta e Lecce), una prevalenza totale di 8,1% per larve di nematodi Anisakidae appartenenti al genere Anisakis, mentre il 27,2% è risultato positivo per larve di Hysterothylacium sp. Le prevalenze riscontrate per Anisakis spp. nelle diverse specie ittiche hanno presentato valori differenti: 1,9% nelle sardine (Sardina pilchardus), 8,6% nelle alici (Engraulis encrasicolus), 17,1% nei naselli (Merluccius merluccius), 44,4% nei suri (Trachurus trachurus), 60,7% nei lanzardi (Scomber colias) e 66,6% negli sgombri (S. scombrus), con rilevanti differenze in relazione all’areale di pesca soprattutto quando comparati ai dati esistenti per le popolazioni ittiche provenienti da areali settentrionali del Mar Adriatico. Le differenze rilevate sono state messe in relazione con le caratteristiche idrologiche, morfologiche ed ecologiche che contraddistinguono i diversi areali adriatici e lo suddividono in due diversi ecosistemi, le cui proprietà incidono in larga misura sulla composizione della comunità faunistica, che include i principali ospiti di Anisakis e si riflette anche sulla sua distribuzione nel tempo e nello spazio. Il Mar Adriatico può essere infatti diviso in una porzione settentrionale definita come un'area costiera neritica ed eutrofica per i fondali poco profondi e i numerosi fiumi dell'Italia settentrionale che immettono abbondante acqua dolce ricca di nutrimento al suo interno, ed una porzione centro-meridionale identificata come un ecosistema di tipo oceanico ed oligotrofico, in quanto i fondali sono molto profondi e la ridotta presenza dei fiumi rende le acque scarse di nutrimento, ma con concentrazione salina elevata. Queste caratteristiche influenzano fortemente la distribuzione e l'abbondanza di molti degli ospiti coinvolti nel ciclo biologico di Anisakis, in particolare quelli intermedi (crostacei eufasiacei) e definitivi (cetacei), portando ad importanti differenze anche nella diffusione degli stadi larvali del parassita nelle popolazioni ittiche marine.

Link: http://docplayer.it/67841225-Anisakiasi-ittica-studio-ecoparassitologico-in-diversi-areali-di-pesca-del-mar-adriatico-centro-meridionale.html

  Haplosporidium pinnae associated with mass mortality in endangered Pinna nobilis (Linnaeus 1758) fan mussels

Autori: PANARESE R, TEDESCO P, CHIMIENTI G, LATROFA M S, QUAGLIO F, PASSANTINO G, BUONAVOGLIA C, GUSTINELLI A, TURSI A, OTRANTO D

Riferimenti: Journal of Invertebrate Pathology (2019) 164: 32-37.

Summary: The fan mussel, Pinna nobilis (Linnaeus 1758), is an endemic bivalve of the Mediterranean basin, protected by international legislation as an endangered species. In the early summer of 2018, a mass mortality event (MME) of P. nobilis was recorded in the Gulf of Taranto (Southern Italy, Ionian Sea). Moribund specimens of P. nobilis were collected by scuba divers and processed by bacteriological, parasitological, histopathological and molecular analyses to investigate the causes of this MME. Different developmental stages (i.e., plasmodia, spores and sporocysts) of a presumptive haplosporidian parasite were observed during the histological analysis in the epithelium and in the lumen of the digestive tubules, where mature spores occurred either free or in sporocysts. The spores presented an operculum and an ovoid shape measuring 4.4 µm (±0.232) in length and 3.6 µm (±0.233) in width. BLAST analysis of an 18SrRNA sequence revealed a high nucleotide similarity (99%) with the reference sequence of Haplosporidium pinnae available in GenBank database. Phylogenetic analysis clustered the sequence of the pathogen in a paraphyletic clade with the reference sequence of H. pinnae, excluding other haplosporidians (i.e., Bonamia and Minchinia genera). Based on data reported, H. pinnae was the causative agent of MME in the populations of P. nobilis sampled in the Ionian Sea, where the conservation of this endangered species is heavily threatened by such a protozoan infection. Further investigations should contribute to knowledge about the life cycle of H. pinnae in order to reduce spread of the pathogen and to mitigate the burden of the disease where P. nobilis is facing the risk of extinction.

Linkhttps://www.ncbi.nlm.nih.gov/pubmed/31026464

  Occurrence of nodular gill disease in farmed brown trout (Salmo trutta L.)

Autori: PEROLO A, GUSTINELLI A, FIORAVANTI ML, MANFRIN A, DALLA POZZA M, LUNELLI F, ACCINI A, QUAGLIO F

Riferimenti: Journal of Fish Diseases (2019)

Summary: Introduction Nodular gill disease (NGD) represents one of the most serious pathology affecting freshwater farmed rainbow trout (Oncorhynchus mykiss) in Italy. This disease has also been observed in arctic char (Salvelinus alpinus) and Chinook salmon (Oncorhynchus tshawytscha) cultured in freshwater environment. The first case of branchitis associated with amoebic infection is detected in farmed brown trout (Salmo trutta L.) in March 2017, during an investigation of NGD in rainbow trout in the province of Trento (Northern Italy). Methodology In a NGD affected rainbow trout farming an outbreak of low mortality occurred in brown trout in one earth tank supplied by spring water with temperature of 6°C. The average weight of the fish was 20-25g. Twenty five fish from the affected tank were collected for necropsy, microscopical and parasitological analysis. Gills were dissected and fixed in 10% neutral buffered formalin solution for histological examination. The samples were dehydrated, embedded in paraffin wax, sectioned (4 µm) and stained with Hematoxylin Eosin and Giemsa solution. Results The fish did not exhibit the typical respiratory symptoms described in NGD of the rainbow trout. The gill tissue appeared pale and swollen at the necropsy with whitish nodules in 9 out of 25 sampled trout. Microscopically numerous Gyrodactylus spp. were observed on the skin. The affected gills showed a proliferative reaction of some filaments, especially in the distal part. These lesions were typical of NGD infection. The microscopic examination of gill tissue revealed the presence of amoebic organisms (approximately 15 x 20 µm). The histology showed multi-focal epithelial hyperplasia of the gills causing lamellar fusion, mucous cells hypertrophy, cellular necrosis and presence of limited number of amoebae along the surface of the affected filaments in 6 out of 25 collected gills. Discussion Despite absence of respiratory symptoms and high mortality rate, gill proliferative lesions associated with amoebae shows that brown trout may be affected by nodular gill disease. Studies are in progress to clarify pathogenesis, biological and environmental determinants of NGD in brown trout and to define the involvement of this species in the spread of the disease in Italian trout farms.

Link: https://onlinelibrary.wiley.com/doi/10.1111/jfd.13027

  Acute phase proteins in marine mammals: state of art, perspectives and challenges

Autori: Gelain ME, Bonsembiante F

Riferimenti: Front Immunol. (2019) 10:1220. doi: 10.3389/fimmu.2019.01220

Summary: The term “acute phase response” (APR) is referred to a nonspecific and complex reaction of an organism that occurs shortly after any tissue damage, such as infection, trauma, neoplasia, inflammation, and stress. The APR can be identified and monitored with some laboratory tests, such as the concentration of several plasma proteins, the acute phase proteins (APPs). The APPs are components of the non-specific innate immune response, and their plasma concentration is proportional to the severity and/or the extent of tissue damage. The evaluation of health status of marine mammals is difficult because the classical clinical signs of illness used for human and domestic animals are difficult to recognize and understand. For this reason, in the past years, several efforts were done to identify laboratory markers of disease in these animals. The APPs have demonstrated their role as early markers of inflammation in veterinary medicine, thus several APPs were tested in marine mammals, such as C-reactive protein (CRP), serum amyloid-A (SAA), and Haptoglobin (Hp). However, the difficulty to extrapolate the knowledge about APPs in one species to another, the lack of specie-specific reagents, the absence of data about negative APPs have hampered their extent use in marine mammals. Herein, the state of art of APPs in marine mammals is reviewed, with particular attention to pre-analytical and analytical factors that should be taken into account in validation and interpretation of APPs assays. Moreover, the current application, potential utility and the future developments of APPs in marine mammals is highlighted and discussed.

Link: https://www.frontiersin.org/articles/10.3389/fimmu.2019.01220/full

  Clinico-pathological findings in striped dolphin (Stenella coeruleoalba) affected by rhabdomyolysis and myoglobinuric nephrosis (capture myopathy)

Autori: Bonsembiante F, Centelleghe C, Rossi G, Giglio S, Madeo E, Gelain ME, Mazzariol S

Riferimenti: J Vet Med Sci. (2017) 79:1013-1018. doi: 10.1292/jvms.17-0023

Summary: A striped dolphin (Stenella coeruleoalba) calf stranded alive because of a Salter-Harris fracture type 1 of a caudal vertebra and remained in a provisional rehabilitation facility for 3 days where the fracture stabilization was attempted, but he died the day after bandaging. Serum and urine samples were collected during hospitalization (days 1, 2 and 3 serum and day 2 urine). Serum analysis showed increased urea, alanine transaminase, aspartate transaminase, and serum amyloid A values, while creatinine was below the lower limit. Urine analysis showed urinary protein-to-creatinine ratio of 5.3 with glomerular proteinuria. Postmortem analyses demonstrated a severe rhabdomyolysis and myoglobinuric nephrosis, suggestive of capture myopathy syndrome. We report, for the first time, the clinico-pathological changes during this condition in a striped dolphin.

Link: https://www.jstage.jst.go.jp/article/jvms/79/6/79_17-0023/_article/-char/en

  Mutations and polymorphism in bottlenose dolphins (Tursiops truncatus, Montagu 1821) albumin gene: first identification of mutations responsible for inherited bisalbuminemia

Autori: Gili C, Bonsembiante F, Beffagna G, Mazzariol S, Gelain ME

Riferimenti: Res Vet Sci. (2017) 114:12-17.  doi: 10.1016/j.rvsc.2017.02.018.

Summary: Hereditary bisalbuminemia is an asymptomatic and heterozygous condition in a range of species characterized by the presence of two serum albumin fractions with different electrophoretic mobility resulting in a bicuspid pattern on serum electrophoresis. Bisalbuminemia has been diagnosed by electrophoresis in two bottlenose dolphin (Tursiops truncatus) families, but causative mutations and the inheritance pattern have not been identified. The aims of this work are: to investigate polymorphisms of the bottlenose dolphin albumin gene and to identify mutations causative of bisalbuminemia; to identify the inheritance pattern in two bottlenose dolphin families. Coding regions of the albumin gene were screened for mutations in 15 bottlenose dolphins kept under human care from two distinct families. Eighteen albumin mutations (three synonymous and 15 non-synonymous) were identified. Two non-synonymous variations co-segregated with bisalbuminemic phenotype: p.Phe146Leu in exon 4 and p.Tyr163His in exon 5. The amino acid change in exon 5 was associated with the secondary and/or tertiary structure variation of the protein and has been reported as causative of bisalbuminemia in humans. Pedigree analysis of the dolphin families showed an autosomal codominant inheritance pattern. In this work, the mutations potentially responsible for bisalbuminemia were identified and confirmed the autosomal codominant trait in bottlenose dolphins.

Link: https://www.sciencedirect.com/science/article/pii/S0034528816308037

  Detection of hereditary bisalbuminemia in bottlenose dolphins (Tursiops truncatus, Montagu 1821). Comparison between capillary zone and agarose gel electrophoresis

Autori: Gili C, Bonsembiante F, Bonanni R, Giordano A, Ledda S, Beffagna G, Paltrinieri S, Sommer M, Gelain ME

Riferimenti: BMC Vet Res (2016) 12:172. doi: 10.1186/s12917-016-0801-x.

Summary: Background Hereditary bisalbuminemia is a relatively rare anomaly characterized by the occurrence of two albumin fractions on serum protein separation by electrophoresis. In human medicine, it is usually revealed by chance, is not been clearly associated with a specific disease and the causative genetic alteration is a point mutation of human serum albumin gene inherited in an autosomal codominant pattern. This type of alteration is well recognizable by capillary zone electrophoresis (CZE), whilst agarose gel electrophoresis (AGE) not always produces a clear separation of albumin fractions. The aims of this study is to report the presence of this abnormality in two separate groups of related bottlenose dolphins and to compare the results obtained with capillary zone and agarose gel electrophoresis.

Results Serum samples from 40 bottlenose dolphins kept under human care were analyzed. In 9 samples a double albumin peak was evident in CZE electrophoresis while no double peak was noted in AGE profile. Since only an apparently wider albumin peaks were noted in some AGE electrophoretic profiles, the ratio between base and height (b/h) of the albumin peak was calculated and each point-value recorded in the whole set of data was used to calculate a receiver operating characteristic curve: when the b/h ratio of albumin peak was equal or higher than 0.25, the sensitivity and specificity of AGE to detect bisalbuminemic samples were 87 and 63 %, respectively. The bisalbuminemic dolphins belong to two distinct families: in the first family, all the siblings derived from the same normal sire were bisalbuminemic, whereas in the second family bisalbuminemia was present in a sire and in two out of three siblings.

Conclusions We report for the first time the presence of hereditary bisalbuminemia in two groups of related bottlenose dolphins identified by means of CZE and we confirm that AGE could fail in the identification of this alteration.

Link: https://bmcvetres.biomedcentral.com/articles/10.1186/s12917-016-0801-x

  Dolphin Morbillivirus in Eurasian Otters, Italy

Autori: Padalino I, Di Guardo G, Carbone A, Troiano P, Parisi A, Galante D, Cafiero MA, Caruso M, Palazzo L, Guarino L, De Riso L, Centelleghe C, Mazzariol S, Petrella A

Riferimenti: Emerg Infect Dis. (2019) Feb; 25(2): 372-374

Summary: We report biomolecular evidence of dolphin morbillivirus in 4 wild Eurasian otters (Lutra lutra) from southern Italy; 2 animals showed simultaneous immunohistochemical reactivity against morbilliviral antigen. These cases add further concern and support to the progressively expanding host range of dolphin morbillivirus in the western Mediterranean Sea.

Link: https://www.ncbi.nlm.nih.gov/pubmed/30666943

  Multidisciplinary studies on a sick-leader syndrome-associated mass stranding of sperm whales (Physeter macrocephalus) along the Adriatic coast of Italy

Autori: Mazzariol S, Centelleghe C, Cozzi B, Povinelli M, Marcer F, Ferri N, Di Francesco G, Badagliacca P, Profeta F, Olivieri V, Guccione S, Cocumelli C, Terracciano G,

Riferimenti: Sci Rep. (2018) Aug 1; 8(1): 11577

Summary: Mass strandings of sperm whales (Physeter macrocephalus) are rare in the Mediterranean Sea. Nevertheless, in 2014 a pod of 7 specimens stranded alive along the Italian coast of the Central Adriatic Sea: 3 individuals died on the beach after a few hours due to internal damages induced by prolonged recumbency; the remaining 4 whales were refloated after great efforts. All the dead animals were genetically related females; one was pregnant. All the animals were infected by dolphin morbillivirus (DMV) and the pregnant whale was also affected by a severe nephropathy due to a large kidney stone. Other analyses ruled out other possible relevant factors related to weather conditions or human activities. The results of multidisciplinary post-mortem analyses revealed that the 7 sperm whales entered the Adriatic Sea encountering adverse weather conditions and then kept heading northward following the pregnant but sick leader of the pod, thereby reaching the stranding site. DMV infection most likely played a crucial role in impairing the health condition and orientation abilities of the whales. They did not steer back towards deeper waters, but eventually stranded along the Central Adriatic Sea coastline, a real trap for sperm whales.

Link: https://www.nature.com/articles/s41598-018-29966-7

  Cetacean host-pathogen interaction(s): Critical knowledge gaps

Autori: Di Guardo G, Centelleghe C, Mazzariol S

Riferimenti: Front Immunol. (2018) Nov 28; 9:2815

Summary: Within the broad range of viral and non-viral pathogens infecting cetaceans, Cetacean Morbillivirus (CeMV), Herpesvirus (HV), Brucella ceti, and Toxoplasma gondii are of special concern, due to their impact(s) on the health and conservation of free-ranging cetacean populations worldwide (1). The most “paradigmatic” example in this direction is represented by CeMV, which throughout the last 3 decades has caused more than 10 mass mortality outbreaks among different cetacean species and populations across the globe (2, 3).

Link: https://www.frontiersin.org/articles/10.3389/fimmu.2018.02815/full

  Death associated to methicillin resistant staphylococcus aureus st8 infection in two dolphins maintained under human care, Italy

Autori: Mazzariol S, Corrò M, Tonon E, Biancani B, Centelleghe C, Gili C

Riferimenti: Front. Immunol. (2018) 9: 2726

Summary: The present study describes the isolation of Methicillin-resistant Staphylococcus aureus (MRSA) from respiratory tract of 2 dolphins of different origin, a stranded juvenile Risso's dolphin (Grampus griseus) and a captive born common bottlenose dolphin (Tursiops truncatus) calf, which died in the same institution at 1-month distance from the other. A complete microbiological and genetic investigation confirmed the presence of MRSA clone-complex 8, sequence type (ST) 8, spa-type t008 in both individuals. This strain differs from the one previously reported in walruses and dolphins and has never been described in dolphins before, but it is randomly isolated from Italian human patients. Vertical transmission of the infection may also occurs in other species and considering the description and location of the pathological lesions, this seems to be the most likely route of transmission implied in the young bottlenose dolphin. Staphylococcus aureus is known as an opportunistic agent, usually secondary to other pathogens, but its multiple antibiotic resistance and its zoonotic implications suggest a thorough and strict application of animal management hygiene protocols.

Link: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6262899/

  Dolphin Morbillivirus in a Cuvier’s Beaked Whale (Ziphius cavirostris), Italy

Autori: Centelleghe C, Beffagna G, Palmisano G, Franzo G, Casalone C, Pautasso A, Giorda F, Di Nocera F, Iaccarino D, Santoro M, Di Guardo G, Mazzariol S

Riferimenti: Front Microbiol. (2017) 8:111

Summary: Dolphin morbillivirus (DMV) has caused several mortality events in Mediterranean striped (Stenella coeruleoalba) and bottlenose (Tursiops truncatus) dolphins populations since 19; in the last 5 years, the virus was reported to infect new hosts in this basin, such as fin whales (Balaenoptera physalus), sperm whales (Physeter macrocephalus), and even a harbor seal (Phoca vitulina). Very recently, a calf Cuvier’s beaked whale (Ziphius cavirostris) calf stranded on the Southern Italian coastline with mild pathological findings suggestive of morbilliviral infection, received the first confirmation of DMV infection in this species by biomolecular evidences on lung tissue. This new cross-species infection report, along with 19% of the cetaceans specimens examined by the Italian Stranding Network being found positive to DMV, support the hypothesis of an endemic circulation of this virus among Mediterranean cetaceans.

Link: https://www.frontiersin.org/articles/10.3389/fmicb.2017.00111/full

  Genomic and structural investigation on dolphin morbillivirus (DMV) in Mediterranean fin whales (Balaenoptera physalus)

Autori: Beffagna G, Centelleghe C, Franzo G, Di Guardo G, Mazzariol S

Riferimenti: Sci Rep. (2017) Jan 30; 7:41554

Summary: Dolphin morbillivirus (DMV) has been deemed as one of the most relevant threats for fin whales (Balaenoptera physalus) being responsible for a mortality outbreak in the Mediterranean Sea in the last years. Knowledge of the complete viral genome is essential to understand any structural changes that could modify virus pathogenesis and viral tissue tropism. We report the complete DMV sequence of N, P/V/C, M, F and H genes identified from a fin whale and the comparison of primary to quaternary structure of proteins between this fin whale strain and some of those isolated during the 1990–‘92 and the 2006–‘08 epidemics. Some relevant substitutions were detected, particularly Asn52Ser located on F protein and Ile21Thr on N protein. Comparing mutations found in the fin whale DMV with those occurring in viral strains of other cetacean species, some of them were proven to be the result of diversifying selection, thus allowing to speculate on their role in host adaptation and on the way they could affect the interaction between the viral attachment and fusion with the target host cells.

Link: https://www.nature.com/articles/srep41554

  Dolphin Morbillivirus Associated with a Mass Stranding of Sperm Whales, Italy

Autori: Mazzariol S, Centelleghe C, Di Provvido A, Di Renzo L, Cardeti G, Cersini A, Fichi G, Petrella A, Di Francesco CE, Mignone W, Casalone C, Di Guardo G

Riferimenti: Emerg Infect Dis. (2017) Jan; 23(1): 144-146

Summary: In September 2014, seven sperm whales were stranded along Italy’s Adriatic coastline. Postmortem investigations on 3 female adult whales and 1 male fetus carried by the largest female revealed molecular and immunohistochemical evidence of dolphin morbillivirus infection. A possible role of the virus in the stranding event was considered.

Link: https://wwwnc.cdc.gov/eid/article/23/1/16-0239_article

  Molecular analysis of dolphin morbillivirus: a new sensitive detection method based on nested RT-PCR

Autori: Centelleghe C, Beffagna G, Zanetti R, Zappulli V, Di Guardo G, Mazzariol S

Riferimenti: J Virol Methods. (2016) Sep; 235: 85-91

Summary: Cetacean Morbillivirus (CeMV) has been identified as the most pathogenic virus for cetaceans. Over the past three decades, this RNA virus has caused several outbreaks of lethal disease in odontocetes and mysticetes worldwide. Isolation and identification of CeMV RNA is very challenging in whales because of the poor preservation status frequently shown by tissues from stranded animals. Nested reverse transcription polymerase chain reaction (nested RT-PCR) is used instead of conventional RT-PCR when it is necessary to increase the sensitivity and the specificity of the reaction. This study describes a new nested RT-PCR technique useful to amplify small amounts of the cDNA copy of Cetacean morbillivirus (CeMV) when it is present in scant quantity in whales’ biological specimens. This technique was used to analyze different tissues (lung, brain, spleen and other lymphoid tissues) from one under human care seal and seven cetaceans stranded along the Italian coastline between October 2011 and September 2015. A well-characterized, 200 base pair (bp) fragment of the dolphin Morbillivirus (DMV) haemagglutinin (H) gene, obtained by nested RT-PCR, was sequenced and used to confirm DMV positivity in all the eight marine mammals under study. In conclusion, this nested RT-PCR protocol can represent a sensitive detection method to identify CeMV-positive, poorly preserved tissue samples. Furthermore, this is also a rather inexpensive molecular technique, relatively easy to apply.

Link: https://www.sciencedirect.com/science/article/pii/S0166093416300350?via%3Dihub

  Mediterranean Fin Whales (Balaenoptera physalus) Threatened by Dolphin MorbilliVirus

Autori: Mazzariol S, Centelleghe C, Beffagna G, Povinelli M, Terracciano G, Cocumelli C, Pintore A, Denurra D, Casalone C, Pautasso A, Di Francesco CE, Di Guardo G

Riferimenti: Emerg Infect Dis. (2016) Feb; 22: N°2

Summary: During 2011–2013, dolphin morbillivirus was molecularly identified in 4 stranded fin whales from the Mediterranean Sea. Nucleoprotein, phosphoprotein, and hemagglutinin gene sequences of the identified strain were highly homologous with those of a morbillivirus that caused a 2006–2007 epidemic in the Mediterranean. Dolphin morbillivirus represents a serious threat for fin whales.

Link: https://wwwnc.cdc.gov/eid/article/22/2/15-0882_article

  Retrospective seroepidemiological investigations against Morbillivirus, Toxoplasma gondii and Brucella spp. in cetaceans stranded along the Italian coastline (1998-2014)

Autori: Profeta F, Di Francesco CE, Marsilio F, Mignone W, Di Nocera F, De Carlo E, Lucifora G, Pietroluongo G, Baffoni M, Cocumelli C, Eleni C, Terracciano G, Ferri N, Di Francesco G, Casalone C, Pautasso A, Mazzariol S, Centelleghe C, Di Guardo G

Riferimenti: Res Vet Sci. (2015) Aug; 101:89-92

Summary: This study reports the results of seroepidemiological investigations carried out against Morbillivirus, Toxoplasma gondii and Brucella spp. on blood serum samples collected from 70 cetacean specimens found stranded along the Italian coastline between 1998 and 2014. A total number of 23 serum samples (32.8%) obtained from Stenella coeruleoalba, Tursiops truncatus, Balaenoptera physalus and Globicephala melas harboured anti-Morbillivirus neutralizing antibodies. Ten sera (16%) collected from S. coeruleoalba and T. truncatus were found positive against T. gondii, while no antibodies against Brucella spp. were found. These data reveal that stranded cetaceans provide a unique opportunity for monitoring the health status of free-ranging animals living in the Mediterranean Sea, in order to investigate the level of exposure of cetacean populations to selected infectious agents representing a serious threat for aquatic mammals.

Link: https://www.sciencedirect.com/science/article/abs/pii/S0034528815300011?via%3Dihub

  Western blot expression of 5-lipoxygenase in the brain from striped dolphins (Stenella coeruleoalba) and bottlenose dolphins (Tursiops truncatus) with or without encephalitis/meningo-encephalitis of infectious nature

Autori: Di Guardo G, Falconi A, Di Francesco A, Mazzariol S, Centelleghe C, Casalone C, Pautasso A, Cocumelli C, Eleni C, Petrella A, Di Francesco CE, Sabatucci A, Leonardi L, Serroni A, Marsili L, Storelli MM, Giacominelli-Stuffler R

Riferimenti: J Biol Regul Homeost Agents (2015) Jan-Mar; 29(1): 245-50

Summary: Dolphin Morbillivirus (DMV), Toxoplasma gondii and Brucella ceti are pathogens of major concern for wild cetaceans. Although a more or less severe encephalitis/meningo-encephalitis may occur in striped dolphins (Stenella coeruleoalba) and bottlenose dolphins (Tursiops truncatus) infected by the aforementioned agents, almost no information is available on the neuropathogenesis of brain lesions, including the neuronal and non-neuronal cells targeted during infection, along with the mechanisms underlying neurodegeneration. We analyzed 5-lipoxygenase (5-LOX) expression in the brain of 11 striped dolphins and 5 bottlenose dolphins, affected or not by encephalitic lesions of various degrees associated with DMV, T. gondii and B. ceti. All the 8 striped dolphins with encephalitis showed a more consistent 5-LOX expression than that observed in the 3 striped dolphins showing no morphologic evidence of brain lesions, with the most prominent band intensity being detected in a B. ceti-infected animal. Similar results were not obtained in T. gondii-infected vs T. gondii-uninfected bottlenose dolphins. Overall, the higher 5-LOX expression found in the brain of the 8 striped dolphins with infectious neuroinflammation is of interest, given that 5-LOX is a putative marker for neurodegeneration in human patients and in experimental animal models. Therefore, further investigation on this challenging issue is also needed in stranded cetaceans affected by central neuropathies.

Link: https://www.ncbi.nlm.nih.gov/pubmed/25864766

  Comparative histopathologic and viral immunohistochemical studies on CeMV infection among Western Mediterranean, Northeast-Central, and Southwestern Atlantic cetaceans

Autori: Diaz-Delgado J, Groch KR, Sierra E, Sacchini S, Zucca D, Quesada-CanalesO, Arbelo M, Fernandez A, Santos E, Ikeda J, Carvalho R, Azevedo AF, Lailson-Brito J, Flach L, Ressio R, Kanamura CT, Sansone M, Favero C, Porter BF, Centelleghe C, Mazzariol S, Di Renzo L, Di Francesco G, Di Guardo G, Catão-Dias JL

Riferimenti: PLoS ONE (2019) 14(3): e0213363.

Summary: Cetacean morbillivirus (CeMV) is a major natural cause of morbidity and mortality in cetaceans worldwide and results in epidemic and endemic fatalities. The pathogenesis of CeMV has not been fully elucidated, and questions remain regarding tissue tropism and the mechanisms of immunosuppression. We compared the histopathologic and viral immunohistochemical features in molecularly confirmed CeMV-infected Guiana dolphins (Sotalia guianensis) from the Southwestern Atlantic (Brazil) and striped dolphins (Stenella coeruleoalba) and bottlenose dolphins (Tursiops truncatus) from the Northeast-Central Atlantic (Canary Islands, Spain) and the Western Mediterranean Sea (Italy). Major emphasis was placed on the central nervous system (CNS), including neuroanatomical distribution of lesions, and the lymphoid system and lung were also examined. Eleven Guiana dolphins, 13 striped dolphins, and 3 bottlenose dolphins were selected by defined criteria. CeMV infections showed a remarkable neurotropism in striped dolphins and bottlenose dolphins, while this was a rare feature in CeMV-infected Guiana dolphins. Neuroanatomical distribution of lesions in dolphins stranded in the Canary Islands revealed a consistent involvement of the cerebrum, thalamus, and cerebellum, followed by caudal brainstem and spinal cord. In most cases, Guiana dolphins had more severe lung lesions. The lymphoid system was involved in all three species, with consistent lymphoid depletion. Multinucleate giant cells/syncytia and characteristic viral inclusion bodies were variably observed in these organs. Overall, there was widespread lymphohistiocytic, epithelial, and neuronal/neuroglial viral antigen immunolabeling with some individual, host species, and CeMV strain differences. Preexisting and opportunistic infections were common, particularly endoparasitism, followed by bacterial, fungal, and viral infections. These results contribute to understanding CeMV infections in susceptible cetacean hosts in relation to factors such as CeMV strains and geographic locations, thereby establishing the basis for future neuro- and immunopathological comparative investigations.

Link: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0213363

  Comparative Immunopathology of Cetacean morbillivirus Infection in Free-Ranging Dolphins From Western Mediterranean, Northeast-Central, and Southwestern Atlantic

Autori: Díaz-Delgado J, Groch KR, Ressio R, Riskallah IPJ, Sierra E, Sacchini S, Quesada-Canales Ó, Arbelo M, Fernández A, Santos-Neto E, Ikeda J, Carvalho RR, Azevedo AF, Lailson-Brito J Jr, Flach L, Kanamura CT, Fernandes NCCA, Cogliati B, Centelleghe C, Mazzariol S, Di Renzo L, Di Francesco G, Di Guardo G and Catão-Dias JL

Riferimenti: Front. Immunol. (2019) 10:485

Summary: Cetacean morbillivirus (CeMV; Paramyxoviridae) causes epizootic and interepizootic fatalities in odontocetes and mysticetes worldwide. Studies suggest there is different species-specific susceptibility to CeMV infection, with striped dolphins (Stenella coeruleoalba), bottlenose dolphins (Tursiops truncatus), and Guiana dolphins (Sotalia guianensis) ranking among the most susceptible cetacean hosts. The pathogenesis of CeMV infection is not fully resolved. Since no previous studies have evaluated the organ-specific immunopathogenetic features of CeMV infection in tissues from infected dolphins, this study was aimed at characterizing and comparing immunophenotypic profiles of local immune responses in lymphoid organs (lymph nodes, spleen), lung and CNS in CeMV-molecularly (RT-PCR)-positive cetaceans from Western Mediterranean, Northeast-Central, and Southwestern Atlantic. Immunohistochemical (IHC) analyses targeted molecules of immunologic interest: caspase 3, CD3, CD20, CD57, CD68, FoxP3, MHCII, Iba1, IFNγ, IgG, IL4, IL10, lysozyme, TGFβ, and PAX5. We detected consistent CeMV-associated inflammatory response patterns. Within CNS, inflammation was dominated by CD3+ (T cells), and CD20+ and PAX5+ (B cells) lymphocytes, accompanied by fewer Iba1+, CD68+, and lysozyme+ histiocytes, mainly in striped dolphins and bottlenose dolphins. Multicentric lymphoid depletion was characterized by reduced numbers of T cells and B cells, more pronounced in Guiana dolphins. Striped dolphins and bottlenose dolphins often had hyperplastic (regenerative) phenomena involving the aforementioned cell populations, particularly chronically infected animals. In the lung, there was mild to moderate increase in T cells, B cells, and histiocytes. Additionally, there was a generalized increased expression of caspase 3 in lymphoid, lung, and CNS tissues. Apoptosis, therefore, is believed to play a major role in generalized lymphoid depletion and likely overt immunosuppression during CeMV infection. No differences were detected regarding cytokine immunoreactivity in lymph nodes, spleen, and lung from infected and non-infected dolphins by semiquantitative analysis; however, there was striking immunoreactivity for IFNγ in the CNS of infected dolphins. These novel results set the basis for tissue-specific immunophenotypic responses during CeMV infection in three highly susceptible delphinid species. They also suggest a complex interplay between viral and host's immune factors, thereby contributing to gain valuable insights into similarities, and differences of CeMV infection's immunopathogenesis in relation to body tissues, CeMV strains, and cetacean hosts.

Link: https://www.frontiersin.org/articles/10.3389/fimmu.2019.00485/full

  Parasitological and pathological findings in fin whales Balaenoptera physalus stranded along Italian coastlines

Autori: Marcer F, Marchiori E, Centelleghe C, Ajzenberg D, Gustinelli A, Meroni V, Mazzariol S

Riferimenti: Dis Aquat Org. (2019) Feb 7; 133: 25–37

Summary: Mediterranean fin whales Balaenoptera physalus face many threats to their conservation, including both anthropogenic and natural issues. There are few records of the parasitic fauna of this species in this geographical area. To partially fill in this gap of knowledge, we investigated the presence and potential impact of parasitic diseases in Mediterranean fin whales. Seven animals stranded along Italian coastlines between 2006 and 2015 were submitted for necropsy and parasitological examination. The protozoan parasite Toxoplasma gondii was detected in 1 fin whale and, for the first time in mysticetes, it was successfully genotyped as a type II strain with 15 microsatellite markers. One crustacean (Pennella spp.) and 4 helminth taxa (Crassicauda boopis, Ogmogaster antarcticus, Tetrabothrius ruudi and Bolbosoma sp.) were detected and morphologically identified. Different degrees of ectoparasitism by adult P. balaenoptera were recorded. Immature stages of Pennella sp. were also detected in 2 animals and are described here for the first time in cetaceans. Infestation by C. boopis was confirmed or suspected in 5 cases. Parasitic thrombi, involving renal veins and caudal vena cava, and fibrosis of renal parenchyma were associated with C. boopis and likely resulted in some degree of renal dysfunction. Larval nematodes were found within foci of mesenteric endarteritis. Further research to evaluate the prevalence of this potentially fatal endoparasitosis in Mediterranean fin whales is warranted.

Link: https://www.ncbi.nlm.nih.gov/pubmed/30997882