56
CARL J . SINDERMANN
has been described by several authors. Jahn and Kuhn (1932) reported
heavy infestation of eyes of Serranidae and Lutianidae by the monogenetic trematode Benedenia melleni (MacCallum). Aquarium fish
carried up to 2 000 worms, attached to eyes, gills and nasal cavities,
and were frequently killed. Survivors usually harbored progressively
fewer parasites ; this decrease was attributed to development of local
immunity and to immune mechanisms of the host mucus (Nigrelli and
Breder, 1934 ; Nigrelli, 1935a, 1935b, 1935c, 1937, 1947). Immunity
to other helminth parasites of fishes has not been demonstrated.
VIII. DISEASES IN MARINE AQUARIA
Disease control has become of increasing significance with the
establishment of many new marine aquaria, oceanaria and hatcheries,
where marine fishes are caught, often a t great expense, and held in
captivity or actually reared under hatchery conditions. Whatever
their original purpose, such artificial conditions should prove to be
fruitful sources of information about diseases and epizootics in marine
fishes and should also provide the needed stimulus to develop understanding of the pathogens concerned. A new technology of treatment
of marine fish diseases, including many modifications of techniques
used in fresh-water hatcheries and aquaria, is slowly developing
(Nigrelli, 1943; Laird, 1956; Chlupaty, 1962; DeGraff, 1962; Hprjgaard,
1962; Oppenheimer, 1962; Paccaud, 1962) and should expand greatly
in the next decade.
As has been true in fresh water, many of the real advances in
understanding the role of fish diseases in the sea can be expected from
studies of individuals in captivity. This has been and will be true
especially of the infectious diseases, which may in epizootic form
sweep through aquarium populations, or in enzootic form result in
continued attrition of valuable specimens. Several references t o
diseases in aquarium environments have already been made in this
paper.
Infectious diseases are easily imported with fish from natural
habitats, and flourish in an artificial environment because of increased
effectiveness of transmission from fish to fish in a restricted body of
water, because of somewhat higher environmental temperatures, or
because of inadequate diet and consequent reduction in resistance.
Fish in captivity are subject to much closer scrutiny than is ever
possible in the sea, so abnormalities are more likely to be observed.
Also, the absence of predators in most aquarium situations permits
abnormal individuals (for example fish with advanced tumors) to live
far beyond what would be their survival time in nature. As pointed
CARL J . SINDERMANN
has been described by several authors. Jahn and Kuhn (1932) reported
heavy infestation of eyes of Serranidae and Lutianidae by the monogenetic trematode Benedenia melleni (MacCallum). Aquarium fish
carried up to 2 000 worms, attached to eyes, gills and nasal cavities,
and were frequently killed. Survivors usually harbored progressively
fewer parasites ; this decrease was attributed to development of local
immunity and to immune mechanisms of the host mucus (Nigrelli and
Breder, 1934 ; Nigrelli, 1935a, 1935b, 1935c, 1937, 1947). Immunity
to other helminth parasites of fishes has not been demonstrated.
VIII. DISEASES IN MARINE AQUARIA
Disease control has become of increasing significance with the
establishment of many new marine aquaria, oceanaria and hatcheries,
where marine fishes are caught, often a t great expense, and held in
captivity or actually reared under hatchery conditions. Whatever
their original purpose, such artificial conditions should prove to be
fruitful sources of information about diseases and epizootics in marine
fishes and should also provide the needed stimulus to develop understanding of the pathogens concerned. A new technology of treatment
of marine fish diseases, including many modifications of techniques
used in fresh-water hatcheries and aquaria, is slowly developing
(Nigrelli, 1943; Laird, 1956; Chlupaty, 1962; DeGraff, 1962; Hprjgaard,
1962; Oppenheimer, 1962; Paccaud, 1962) and should expand greatly
in the next decade.
As has been true in fresh water, many of the real advances in
understanding the role of fish diseases in the sea can be expected from
studies of individuals in captivity. This has been and will be true
especially of the infectious diseases, which may in epizootic form
sweep through aquarium populations, or in enzootic form result in
continued attrition of valuable specimens. Several references t o
diseases in aquarium environments have already been made in this
paper.
Infectious diseases are easily imported with fish from natural
habitats, and flourish in an artificial environment because of increased
effectiveness of transmission from fish to fish in a restricted body of
water, because of somewhat higher environmental temperatures, or
because of inadequate diet and consequent reduction in resistance.
Fish in captivity are subject to much closer scrutiny than is ever
possible in the sea, so abnormalities are more likely to be observed.
Also, the absence of predators in most aquarium situations permits
abnormal individuals (for example fish with advanced tumors) to live
far beyond what would be their survival time in nature. As pointed