492
JOHN E. CUSHINC
Sindermann’s review adds a number of references that complement
those of Ridgway et al. (1966) concerned with aspects of the immunization of fishes. These reviews both include those on efforts, sometimes
partially successful, to protect fish such as salmonids from hatchery diseases and to show that oral and other forms of immunization hold considerable promise (cf. Ross and Klontz, 1965). Additionally, Sindermann
presents reasons for believing that some diseases of marine fishes may
come to be controllable, not, probably, by giving them “shots,” but by
manipulating their ecology so that they can develop their own immunities, either active or ecological. Among the many interesting observations discussed by Sindermann is that of Nigrelli and Breeder
(cf. Nigrelli, 1947) that trematode infections are in part combated by
immunological reactions in fish mucus. This substance, so abundantly
produced, apparently can acquire protective properties and offers
opportunities for research. Attention is called to the paper of Hildemann
(1959) showing that the newly hatched fry of the cichlid fish, Symphysodon discus, feed exclusively on an abundant mucus secretion produced over the skin of both parents. It is possible that this highly
specialized diet may have immunological as well as nutritional attributes,
and other kinds of mucoid relations between parents, eggs, and young
might be investigated from such a point of view.
The so-called natural antibodies of fish present an additional area
of interest. The antibodies are to be found in essentially all “normal”
serums investigated and are detected by their ability to agglutinate
erythrocytes that can come from a variety of species, ranging from
those of different individuals in the same species to other fishes and on
to birds and mammals. These are often highly specific and include
antibodies that recognize human antigens of ABO and other systems.
One such antibody, long known, is that found in serums of marine eels
that has anti-H activity (reacting most strongly with 0- and A,-type
cells, cf. Race and Sanger, 1968). These antibodies appear to be generated by infections or by normal intestinal flora. Support for this
concept derives from seasonal fluctuations observed among them, for
example, as found in the brown bullhead (Cushing and Durall, 1957)
and the winter skate (Sindermann and Honey, 1964). These fluctuations
have been partially correlated with bacterial contamination in some
freshwater species by Bisset (1948) and emphasize, as has been pointed
out by Noble (1957, 1960), the continued need to maintain an ecological
point of view in the study of fish parasites and their effects. Medical
significance is attached to fish natural agglutinins in the paper of Janssen
and Meyers (1968) who find that the serums of white perch, Roccus
americanus, taken adjacent to heavily populated areas of Chesapeake
JOHN E. CUSHINC
Sindermann’s review adds a number of references that complement
those of Ridgway et al. (1966) concerned with aspects of the immunization of fishes. These reviews both include those on efforts, sometimes
partially successful, to protect fish such as salmonids from hatchery diseases and to show that oral and other forms of immunization hold considerable promise (cf. Ross and Klontz, 1965). Additionally, Sindermann
presents reasons for believing that some diseases of marine fishes may
come to be controllable, not, probably, by giving them “shots,” but by
manipulating their ecology so that they can develop their own immunities, either active or ecological. Among the many interesting observations discussed by Sindermann is that of Nigrelli and Breeder
(cf. Nigrelli, 1947) that trematode infections are in part combated by
immunological reactions in fish mucus. This substance, so abundantly
produced, apparently can acquire protective properties and offers
opportunities for research. Attention is called to the paper of Hildemann
(1959) showing that the newly hatched fry of the cichlid fish, Symphysodon discus, feed exclusively on an abundant mucus secretion produced over the skin of both parents. It is possible that this highly
specialized diet may have immunological as well as nutritional attributes,
and other kinds of mucoid relations between parents, eggs, and young
might be investigated from such a point of view.
The so-called natural antibodies of fish present an additional area
of interest. The antibodies are to be found in essentially all “normal”
serums investigated and are detected by their ability to agglutinate
erythrocytes that can come from a variety of species, ranging from
those of different individuals in the same species to other fishes and on
to birds and mammals. These are often highly specific and include
antibodies that recognize human antigens of ABO and other systems.
One such antibody, long known, is that found in serums of marine eels
that has anti-H activity (reacting most strongly with 0- and A,-type
cells, cf. Race and Sanger, 1968). These antibodies appear to be generated by infections or by normal intestinal flora. Support for this
concept derives from seasonal fluctuations observed among them, for
example, as found in the brown bullhead (Cushing and Durall, 1957)
and the winter skate (Sindermann and Honey, 1964). These fluctuations
have been partially correlated with bacterial contamination in some
freshwater species by Bisset (1948) and emphasize, as has been pointed
out by Noble (1957, 1960), the continued need to maintain an ecological
point of view in the study of fish parasites and their effects. Medical
significance is attached to fish natural agglutinins in the paper of Janssen
and Meyers (1968) who find that the serums of white perch, Roccus
americanus, taken adjacent to heavily populated areas of Chesapeake