Relationship between liver tumors and age in brown bullhead populations from two Lake Erie tributaries.
Sci Total Environ
; 94(1-2): 71-87, 1990 May 01.
Article
en En
| MEDLINE
| ID: mdl-2360040
ABSTRACT
We compared liver tumor frequencies, and age and length characteristics of brown bullheads (Ictalurus nebulosus) of greater than 250 mm total length from two Lake Erie tributaries. Bullheads taken from Old Woman Creek (n = 144) had no grossly observable liver tumors, while those collected in the highly industrialized Black River (n = 532) had a 30% frequency of grossly visible liver tumors during 1981-1982. Liver lesions diagnosed histologically in a randomly collected sample (n = 125) of brown bullheads from the Black River included both biliary and hepatic lesions, with cancerous neoplasms occurring in 38.4% of the fish. Black River bullheads of combined ages 4 and 5 had a significantly (p less than or equal to 0.05) greater prevalence of biliary carcinomas (35.5%) than those of ages 2 and 3 combined (18.4%). Biliary carcinoma was significantly more prevalent than hepatocellular carcinoma in age 4 fish (sexes combined) and in males of ages 3 and 4. The prevalence of hepatocellular carcinoma was significantly higher in females than in males. Age distributions of bullheads differed significantly between the two sites, while length distributions were similar. No brown bullheads of ages 6 or 7 were collected in the Black River, while these age groups composed 18% of the catch in Old Woman Creek. Brown bullheads of age 5 were almost six times more numerous in the Old Woman Creek than in Black River collections. These age and length distributions are consistent with the hypothesis that brown bullheads in the Black River were subjected to an age-selective mortality associated with high prevalences of liver carcinoma.
Buscar en Google
Banco de datos:
MEDLINE
Asunto principal:
Enfermedades de los Peces
/
Peces
/
Neoplasias Hepáticas
Tipo de estudio:
Risk_factors_studies
Límite:
Animals
País/Región como asunto:
America do norte
Idioma:
En
Revista:
Sci Total Environ
Año:
1990
Tipo del documento:
Article