Pathologie des infections par les morbillivirus chez les mammifères marins

Morbillivirus infections were described since 1988 in marine mammals including pinnipeds and cetaceans. Since, numerous outbreaks, responsible for thousands marine mammals death, as well as sporadic cases, have occurred in various populations from North Atlantic, Mediterranean Sea, Baikal Lake, Caspian Sea, and recently from northern Pacific. Clinical signs and macroscopic lesions are similar between species infected by morbillivirus and are close to those reported in dog with canine distemper. Under microscope, characteristic les ions are interstitial bronchopneumonia, lymphoid depletion and subacute encephalitis. Syncytia and inclusion bodies are frequently observed in lesions and epithelia. Lymphoid depletion promotes secondary infections by opportunistic pathogens, responsible in many cases of the animals death. Various parameters explain the high sensibility of certain population such as the species, the naive immunological status and vectors intervention for the disease

On the stranding of 4 sperm whales on the Belgian coast, November 18, 1994

Male sperm whales found dead on the coast of Belgium in November 1994 had suffered a weight deficit and displayed debilitating lesions. High levels of Cd, Hg, PCB's and DDE contamination affected all four animals. A combination of these factors could explain the stranding

Postmortem investigations on winter stranded sperm whales from the coasts of Belgium and the Netherlands

During winter 1994-95, four and three sperm whales (Physeter macrocephalus) were stranded along the Belgian and the Dutch coasts, respectively. Necropsies and tissue samplings were collected 24 hrs post mortem. Lesions on several whales included round and linear skin scars, ventral skin abrasions, acute skin ulcers, acute ulcerative stomatitides, acute to chronic external otitides, and passive visceral congestion. In addition, these sperm whales appeared to be debilitated with severe weight deficit, had blubber thickness reduction, the absence of abdominal fat, and the intestinal tracts were almost empty. Three categories of lesions and their possible relation with the stranding were evaluated. Cutaneous scars observed on the seven whales appeared to have no relation with the stranding. The poor body condition and acute integument ulcerative lesions were present before the stranding. Ventral skin abrasions and visceral passive congestion were caused by the strandings. Absence of food in the alimentary tracts, evidence of weight loss and blubber thickness reduction were compatible with an extended presence of the sperm whales in the North Sea, where adequate food is not available. This might lead to progressive weakness, predisposing the animals to secondary pathogens such as viral diseases. Finally, the coastal configuration of the southern North Sea makes it a trap for sperm whales which have entered the area during their wanderings

Post-mortem findings and causes of death of harbour porpoises (Phocoena phocoena) stranded from 1990 to 2000 along the coastlines of Belgium and northern France

peer reviewedBetween the,ears 1990 and 2000, an attempt was made to determine the causes of death of 55 harbour porpoises stranded along the Belgian and northern French coasts. From 1990 to 1996, only five carcasses were collected as against seven in 1997, eight in 1998, 27 in 1999 and eight in 2000. The sex ratio was normal and most of the animals were juvenile. The most common findings were emaciation, severe parasitosis and pneumonia. A few cases of fishing net entanglement were observed. The main microscopical lesions were acute pneumonia, massive lung oedema, enteritis, hepatitis and gastritis. Encephalitis was observed in six cases. No evidence of morbillivirus infection was detected. Pneumonia was associated with bacteria or parasites, or both. The causes of death and the lesions were similar to those previously reported in other countries bordering the North Sea. The cause of the increased numbers of carcasses in 1999 was unclear but did not include viral epizootics or net entanglement. A temporary increase in the porpoise populatiou in the southern North Sea may have been responsible. (C) 2002 Elsevier Science Ltd. All rights reserved