SOM I< ASPEW" 01' NEt IPLASlA IN MARTN E AKIMALS
171
strides arc being made in thv ideiitificntion of the viruses known to cause
fish diseases and fish neoplwsia. The possible palat played by oncogenic
viruses has dreiidy been mentioned in fish-pox, an extreme epithelial
hyperplasiii seeii in some specim, also the stotnato-papillomatosis of
eels could well have it viral aetiology, as has the possible connection
betwcen the lymphosarcomsta seen in the Irish Pike E'sox ZuciuS L.,
Marek's disease in aviaii species and Burkett's lymphoma in man.
Until more laboratories hold sevwul fish cell lines and have expertise in
electron microscopy progress will not be spectacular.
Fish which live at t h r bottom of tho oc*ean inay expose themselves
to local tntuma by scraping thcrnnelves against a " rough " sea bed.
Skin damtigo is oftcn the end result and, although often minor in itself,
can be R potential site of entry of oricogeiiic viruses. The incidence of
xkin papillomata in the Bothidae and Yleuronectidae could well attest
to such an aetiology. Another predisposing factor is that, if there is
carcinogenic mriterial anywhere in the water, it is more likely to
accumirlatc on the sea or estuarine floor.
The relationship between phylogeny and oncogeny was initially
thought to be absolute and it was believed that neoplastic transformation depended on the presence or absence of a lymphoid system, upon
which the iinmuw response was dependent,. The exact immunological
response of fish to tumours requires further work and discussion. Some
tumours have been successfully trctnsplanted. This work was performed
in the early 1!)40s (Luck6 and Hchlumbergcr, 1941) in which auto- and
homo-tr~~ns~~li~nts showed contiiiried growth (Good and Papermaster,
1964). I'hc ahtrophy of the lymphoid systclm with age, as seen in many
of the higher animals, could well bc associated with the high incidence
of neoplmstic. trimsformation seen in middle to old age, according to the
species studied. Sonic strains of rats develop nearly 100% mammary
tumours by 2 years of age. Sintilarly, some female strains of rats can
develop u p to 80% pituitary tumours. Some work has been undertaken
on the immune response of several fish species, including some Salmonidae, in relation to various infectious agents (Klontz, 1972; Dorson,
1972). Antigenic variations in 76 virus isolates of Egtved disease have
been examined wing fluorescent antibody techniques (Vestergard
Jnrrgensen, 1972).
Some tiimours of marine fish which have been seen at the Huntingdon Research Centre are illustrated in the following pageg (Figs. 11-21).
171
strides arc being made in thv ideiitificntion of the viruses known to cause
fish diseases and fish neoplwsia. The possible palat played by oncogenic
viruses has dreiidy been mentioned in fish-pox, an extreme epithelial
hyperplasiii seeii in some specim, also the stotnato-papillomatosis of
eels could well have it viral aetiology, as has the possible connection
betwcen the lymphosarcomsta seen in the Irish Pike E'sox ZuciuS L.,
Marek's disease in aviaii species and Burkett's lymphoma in man.
Until more laboratories hold sevwul fish cell lines and have expertise in
electron microscopy progress will not be spectacular.
Fish which live at t h r bottom of tho oc*ean inay expose themselves
to local tntuma by scraping thcrnnelves against a " rough " sea bed.
Skin damtigo is oftcn the end result and, although often minor in itself,
can be R potential site of entry of oricogeiiic viruses. The incidence of
xkin papillomata in the Bothidae and Yleuronectidae could well attest
to such an aetiology. Another predisposing factor is that, if there is
carcinogenic mriterial anywhere in the water, it is more likely to
accumirlatc on the sea or estuarine floor.
The relationship between phylogeny and oncogeny was initially
thought to be absolute and it was believed that neoplastic transformation depended on the presence or absence of a lymphoid system, upon
which the iinmuw response was dependent,. The exact immunological
response of fish to tumours requires further work and discussion. Some
tumours have been successfully trctnsplanted. This work was performed
in the early 1!)40s (Luck6 and Hchlumbergcr, 1941) in which auto- and
homo-tr~~ns~~li~nts showed contiiiried growth (Good and Papermaster,
1964). I'hc ahtrophy of the lymphoid systclm with age, as seen in many
of the higher animals, could well bc associated with the high incidence
of neoplmstic. trimsformation seen in middle to old age, according to the
species studied. Sonic strains of rats develop nearly 100% mammary
tumours by 2 years of age. Sintilarly, some female strains of rats can
develop u p to 80% pituitary tumours. Some work has been undertaken
on the immune response of several fish species, including some Salmonidae, in relation to various infectious agents (Klontz, 1972; Dorson,
1972). Antigenic variations in 76 virus isolates of Egtved disease have
been examined wing fluorescent antibody techniques (Vestergard
Jnrrgensen, 1972).
Some tiimours of marine fish which have been seen at the Huntingdon Research Centre are illustrated in the following pageg (Figs. 11-21).