Geology topics
R. L. Herman
Publications and source records attributed to R. L. Herman.
Icthyophonus-like infection in newts (Notophthalmus viridescens Rafinesque)
No abstract available.
Glomerular mesangial fibrosis in hatchery-reared rainbow trout (Salmo gairdneri)
Light and electron microscopic studies were performed on tissues of hatchery-reared rainbow trout ( Salmo gairdneri ) having a disease of currently unknown etiology with external symptoms of severe edema which causes increased mortality rate. Comparison with unaffected trout tissues revealed loss of cellularity in glomerular tufts with a replacement of mesangial cells by connective tissue. Ultrastructural studies showed the material to be collagen and established the diagnosis of glomerular mesangial fibrosis. The glomerular lesion was associated with alterations in lining epithelium of proximal tubules and extensive debris within tubule lumens. The findings are compared to glomerular lesions in mammalian and amphibian kidney.
Comparative susceptibility of Atlantic salmon (Salmo salar) to the enteric redmouth bacterium and Aeromonas salmonicida
The bacterium causing enteric redmouth (ERM) and Aeromonas salmonicida were found to be equally pathogenic for fingerling Atlantic salmon ( Salmo salar ). Injection of 5 × 10 5 cells of ERM or A. salmonicida killed all salmon within 96 h. After a 30 min exposure to water-borne cells of the two test bacteria about one-half of the test salmon died within 14 days. Both ERM and A. salmonicida were transmitted horizontally. Results indicate that efforts should be made to prevent introduction of ERM into watersheds where Atlantic salmon occur.
A testicular leiomyoma in a largemouth bass, Micropterus salmoides
No abstract available.
Salmonid viruses : effects of Herpesvirus salmonis in rainbow trout fry
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In vitro and in vivo efficacy of potentiated sulfonamide in control of furunculosis in salmonids
In vitro and in vivo efficacy of a potentiated sulffonamide, Ro5–0037, for inhibition of Aeromonas salmonicida , causative agent of fish furunculosis was determined. The components of the potentiated sulfonamide, sulfadimethoxine, and ormetoprim were tested alone and in combination. In vitro results showed that both sulfonamide-resistant and sensitive strains of A . salmonicida had greater sensitivity to Ro5–0037 than to either of its components. Also, sulfonamide-sensitive strains developed resistance to ormetoprim and sulfadimethoxine more rapidly than to Ro5–0037. Efficacy studies with small numbers of artificially infected trout revealed that Ro5–0037 effectively controlled furunculosis at 50 mg/kg of fish/day, one fourth the usual sulfonamide dosage level. Extensive field trials also showed the 50 mg/kg level of Ro5–0037 gave effective control of hatchery outbreaks of furunculosis. As found in the in vitro studies, all in vivo trials indicated the combination of ormetoprim and sulfadimethoxine was more efficient in inhibiting A . salmonicida than either component alone.
Fish viruses: Histopathologic changes associated with experimental channel catfish virus disease
A histologic examination was carried out on fry with experimentally induced channel catfish virus disease (CCVD). The infection produced a hemorrhagic and necrotic disease with the target organs being the kidneys, liver, digestive tract, and skeletal muscle. The results agree with symptoms of the disease and with published data on quantifications of virus in specific organs.
Visceral granuloma in brook trout (Salvelinus fontinalis)
Brook trout were fed a synthetic diet with suspect diet components added or a meat-meal diet with individual components removed to determine their effect on the incidence of visceral granuloma. Removal or addition of cottonseed meal had the greatest effect on incidence. Gossypol was not the causative agent. The disease is characterized, histologically, by the presence of Langhans-type giant cells and concretions like Schaumann bodies giving an apparent similarity to sarcoidosis in humans. Gross symptoms of the disease are papillary growths of connective tissue on the serosal surface of the stomach, and calcification of the posterior kidney. In severe cases, lesions may be present throughout the visceral mass. Visceral granuloma is similar to nephrocalcinosis in rainbow trout and may be the same disease modified by difference in species response.
Chemotherapy of fish diseases: A review
Fish suffer from environmental, nutritional, viral, bacterial, parasitic, and neoplastic diseases, many of which are similar to those of higher animals. The prevention and treatment of these diseases follow the same principles as diseases of other animals. Fish culture is similar to poultry husbandry in that large numbers of animals are crowded into relatively small areas, feeding is free choice, and medication for systemic infections is usually oral. External treatment of fishes is more common than of poultry, due to a higher frequency of external diseases. Many of the drugs and chemicals used in chemotherapy of fishes are the same as for higher animals. The following is a brief review of the more important drugs and their methods of administration.
A microsporidan (Protozoa: Cnidospora) in channel catfish (Ictalurus punctatus)
No abstract available.
Oxytetracyline efficacy as a pretreatment against columnaris and furunculosis in coho salmon
No abstract available at this time
Oxytetracyline residues in different tissues of trout
No abstract available at this time
Oxytetracycline in fish culture-a review.
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