Saturday, August 2, 2008

Diseases and parasites of dolphins/whales

So saving Brucellosis Bacteria for last, I will go first with the most successful protozoan pathogen "Toxoplasma gondii" a known dolphin killer. And then Crassicaudosis: a parasitic disease threatening the health and population recovery of large baleen whales.
Lambertsen RH.

Ecosystems Technology Transfer, University Science Center, Philadelphia, PA 19104-6068.

This communication briefly reviews knowledge of the systemic disease caused by Crassicauda boopis in blue whales (Balaenoptera musculus), fin whales (B. physalus) and humpback whales (Megaptera novaeangliae). Infections with this giant nematode characteristically incite a chronic inflammatory reaction of the blood vessels which drain the kidneys. In this critical location, the parasite-induced lesion can cause complete vascular occlusion and kidney failure. Whale calves and juveniles typically suffer the heaviest parasite burdens following transplacental infection of the developing whale foetus. There is also probable whale-to-whale transmission post-partum, involving urinary contamination of the environment with C. boopis eggs and larvae. The frequency of the infection can exceed 95%. Haematological findings suggest that systemic pathological effects are typical at the population level. Gradual development of occlusive lesions in the renal veins appears to correlate with a major peak in natural mortality at about one year of age. To date, all findings support the conclusion that premature death caused by C. boopis infection is potentially a major impediment to population recovery of affected whale species. This suggests the interesting possibility of actively encouraging the population recovery of three species of large baleen whales. Such a restoration effort would entail remotely-deployed anthelminthic therapy administered, at sea, to infected whale cows and calves.

PMID: 1305859 [PubMed - indexed for MEDLINE]

Brucellosis Bacteria
A link on its ability to infect humans.
Not the sort of meat I would eat RAW!
And now some quotes on it being found in Minke.

Otsuchi Marine Research Center,
Ocean Research Institute,
The University of Tokyo,
2-106-1, Akahama,
Iwate 028-1102, Japan.

Abnormal testes and uterus were observed in 13 males (33%) and one female (3%) out of 40 common minke whales (Balaenoptera acutorostrata) in the western North Pacific.
Similar lesions were found in testis and ovary, respectively, in one male (2%) and female (2%) out of 43 Bryde's whales (Balaenoptera edeni) in the western North Pacific.
Grossly, granular lesions with caseation and calcification were main pathological signs, and they were restricted to reproductive organs of mature whales.
Chronic purulent or granulomatous orchitis was observed by microscopic analysis.
Antibodies to Brucella species were detected in the serum samples of 15/40 (38%) of common minke whales and 4/43 (9%) of Bryde's whales.
Neither pathological nor serological change was found in the examined sperm whales (Physeter macrocephalus) in the western North Pacific and Antarctic minke whales (Balaenoptera bonaerensis).
These results strongly suggest that Brucella infection was involved in two species of baleen whales (Mysticeti) in the North Pacific.
nervous damage link

The issue of Brucella-contaminated minke whale meat
follows several published papers by Japanese researchers
documenting high levels of mercury and organochlorine
pollutants in cetacean meat products being sold for human
consumption, and warnings about the potential health
risks of consuming these products. For example, research-
ers found that in cetacean meat samples collected from
Japanese markets, mean contamination levels in red meat
0025-326X/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved.

Marine Pollution Bulletin 52 (2006) 1118–1120
Page 2
were 22 and 18 times higher than levels permitted by the
Japanese government for total mercury i.e., 0.4 ppm, with
health safety levels being exceeded by a factor of up to
200 times (Endo et al., 2002, 2003a, 2004, 2005; Simmonds
et al., 2002). Mercury levels in boiled liver were even high-
er, up to 1980 ppm (wet weight) with mean mercury levels
in boiled cetacean liver being considered to be high enough
that ‘‘a single ingestion of the boiled whale [meat] may cause
an acute intoxication’’ (Endo et al., 2003b, p. 416). More-
over, rats fed portions of this contaminated meat showed
signs of kidney abnormalities ingesting just a single dose
(Endo et al., 2003b). Levels of mercury were so high the
researchers stated that they ‘‘could pose a health problem
for not only to pregnant women but also for the general pop-
ulation’’ (Endo et al., 2005, p. 5703) and that ‘‘[m]ore atten-
tion must be paid to the recommendation that whale [organs]
should not be eaten at all’’ (p. 416, Endo et al., 2003b).
There is also a high degree of organochlorine contamina-
tion in cetacean meat products (up to 7.5 ppm wet weight
for DDT and 8.9 ppm for PCBs; Simmonds et al., 2002).
Far from warning Japanese people of the escalating
health risks associated with consuming contaminated ceta-
cean products, the Japanese Government is actively pro-
moting expansion of the market. Somewhat alarmingly,
one of their marketing initiatives is to provide whale meat
to elementary schools for school lunch programs (Kher
and Sekiguchi, 2006). Presumably this marketing is to gen-
erate an interest in consuming cetacean products in the
young, which they presumably believe will be maintained
as these children grow older. However, the ethical and
moral implications of encouraging consumption of meat
products known to be contaminated with mercury, orga-
nochlorines and potentially pathogens, to children who
do not have a choice in the consumption of the products,
is staggering. This is particularly so when one considers
that studies in such areas as the Faeroe Islands have linked
mercury toxicity, in which consumption of mercury-
contaminated cetacean meat may play a major part, to
brain stem damage, mental retardation, and neurological
and heart abnormalities in children (Grandjean et al.,
1997; Steuerwald et al., 2000; Grandjean et al., 2004; Mur-
ata et al., 2004).
The Japanese ‘‘scientific’’ whaling programme has pro-
duced very few peer-reviewed articles (Gales et al., 2005),
so it is ironic when data published in one of these articles
are overlooked, or perhaps wilfully ignored, by the Japa-
nese government.

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