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Marine vertebrates possess numerous pathologic mineral structures. Some of
these examples of abnormal biomineralization (Smith 1982 ) are represented and
discussed below.
Calculi The term calculus is derived from the Latin for “pebble” and is defi ned as
an abnormal concretion occurring within the body. Formation of calculi is known as
lithiasis (Greek: lithos = stone).
Dental Calculi In contrast to well reported cases of pathological conditions on
teeth in primates and mostly in humans, similar situations are particularly very
rare in marine mammals, and in wild animals in general. Only few species of
cetaceans provided scanty records of their dental anomalies. Recently, Loch and
co-workers ( 2011 ) carried out a systematic study of dental pathology in dolphins.
Abnormalities such as mineralized calculus deposits were diagnosed in the delphinids
Delphinus capensis , Orcinus orca , Steno bredanensis , Sotalia guianensis ,
Lagenodelphis hosei, Stenella coeruleoalba , Tursiops truncatus , and Pseudorca
crassidens . Unfortunately, the aetiology of calculus accumulation in these marine
animals remains unknown.
Nasal Calculi Nasal Calculi were observed by Curry et al. ( 1994 ) in the lumens of
posterior nasal sacs and the anterior nasofrontal sacs (for anatomical details see
Mead 1975 ) of eight dolphin specimens: one Australophocaena dioptrica , one
Phocoena spinipinnis , three P. phocoena , and three P. dalli. Although several of
these calculi were completely surrounded by a thin tissue layer, the main fraction of
calculi was embedded within the trabeculate areas and within tiny diverticula within
epithelial layer of the sacs. No infl ammation has been observed in these areas of the
nasal tissue. On cross sections of the calculi isolated from P. dalli some surface
crystals and a “layer of alternating medium tan to lighter tan bands of concentric
laminations with a light tan unoriented central core” (Curry et al. 1994 ) are visible.
The chemical composition of these calculi was as follow: 20 % apatite and 80 %
calcium carbonate (Curry et al. 1994 ).
Up today, there are no data which could explain the mechanisms of abnormal
mineralization within nasal sacs of phocoenid species. However, following suggestions have been reported as summarized by Curry et al. ( 1994 ):
– “abnormal mineralization may be the result of normal tissue healing, following
cell necrosis or ectopic mineralization due to excessive supersaturation;
– compression of nasal diverticula may cause water condensation within the upper
respiratory tract of dolphins. Foreign particulate matter from inspired air or
seawater may remain in the biological fl uids found in the nasofrontal and
posterior nasal sacs, and supersaturation and subsequent mineralization involving
chemical alteration of the foreign substance may occur;
– the calculi are dystrophic calcifi cations of desiccated mucosal secretions
and debris combined with components of seawater,” (Curry et al. 1994 ;
see for more information Smith 1982 ; Simkiss and Wilbur 1989 ; Coulombe
et al. 1965 ).
3.7 Pathological Biomineralization in Marine Vertebrates
Marine vertebrates possess numerous pathologic mineral structures. Some of
these examples of abnormal biomineralization (Smith 1982 ) are represented and
discussed below.
Calculi The term calculus is derived from the Latin for “pebble” and is defi ned as
an abnormal concretion occurring within the body. Formation of calculi is known as
lithiasis (Greek: lithos = stone).
Dental Calculi In contrast to well reported cases of pathological conditions on
teeth in primates and mostly in humans, similar situations are particularly very
rare in marine mammals, and in wild animals in general. Only few species of
cetaceans provided scanty records of their dental anomalies. Recently, Loch and
co-workers ( 2011 ) carried out a systematic study of dental pathology in dolphins.
Abnormalities such as mineralized calculus deposits were diagnosed in the delphinids
Delphinus capensis , Orcinus orca , Steno bredanensis , Sotalia guianensis ,
Lagenodelphis hosei, Stenella coeruleoalba , Tursiops truncatus , and Pseudorca
crassidens . Unfortunately, the aetiology of calculus accumulation in these marine
animals remains unknown.
Nasal Calculi Nasal Calculi were observed by Curry et al. ( 1994 ) in the lumens of
posterior nasal sacs and the anterior nasofrontal sacs (for anatomical details see
Mead 1975 ) of eight dolphin specimens: one Australophocaena dioptrica , one
Phocoena spinipinnis , three P. phocoena , and three P. dalli. Although several of
these calculi were completely surrounded by a thin tissue layer, the main fraction of
calculi was embedded within the trabeculate areas and within tiny diverticula within
epithelial layer of the sacs. No infl ammation has been observed in these areas of the
nasal tissue. On cross sections of the calculi isolated from P. dalli some surface
crystals and a “layer of alternating medium tan to lighter tan bands of concentric
laminations with a light tan unoriented central core” (Curry et al. 1994 ) are visible.
The chemical composition of these calculi was as follow: 20 % apatite and 80 %
calcium carbonate (Curry et al. 1994 ).
Up today, there are no data which could explain the mechanisms of abnormal
mineralization within nasal sacs of phocoenid species. However, following suggestions have been reported as summarized by Curry et al. ( 1994 ):
– “abnormal mineralization may be the result of normal tissue healing, following
cell necrosis or ectopic mineralization due to excessive supersaturation;
– compression of nasal diverticula may cause water condensation within the upper
respiratory tract of dolphins. Foreign particulate matter from inspired air or
seawater may remain in the biological fl uids found in the nasofrontal and
posterior nasal sacs, and supersaturation and subsequent mineralization involving
chemical alteration of the foreign substance may occur;
– the calculi are dystrophic calcifi cations of desiccated mucosal secretions
and debris combined with components of seawater,” (Curry et al. 1994 ;
see for more information Smith 1982 ; Simkiss and Wilbur 1989 ; Coulombe
et al. 1965 ).
3.7 Pathological Biomineralization in Marine Vertebrates