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Geology topics

G. L. Bullock

Publications and source records attributed to G. L. Bullock.

At least 73 records · Page 4Linked to original sources
USGS1974

Corynebacterial kidney disease of salmonids: Growth and serological studies on the causative bacterium

Comparative growth studies of 10 isolates of the Corynebacterium of salmonid kidney disease were quantified on four media. Greatest cell yield was obtained from Mueller-Hinton medium with 0.1% L-cysteine hydrochloride. Serological tests, in which rabbit antisera used against typical bacteria strains showed all to be antigenically homologous, provided a reliable method of identification.

Applied Microbiology↗
USGS1974

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.

Journal of the Fisheries Research Board of Canada↗
USGS1969

Bacteria in blood and kidney of apparently healthy hatchery trout

Aseptic examination of blood and kidney material from three species of apparently healthy trout at two hatcheries showed that 12.5% of examined trout at one hatchery and 26.1% of trout at the other carried low numbers of bacteria. In addition, sera from these trout had agglutinins against some of the isolated bacteria and bacterial types found in trout were the same as those cultured from raceway water in which fish were raised. Although the presence of these bacteria does not constitute a disease state, the potential for an epizootic is present should trout be placed under stress conditions.

Transactions of the American Fisheries Society↗
USGS1968

Infectious pancreatic necrosis: Selection of virus-free stock from a population of carrier trout

Infectious pancreatic necrosis (IPN) is a virulent disease of young trouts and is easily transmitted from infected animals through water and with eggs. At present, the most effective control measure consists of propagation of specific pathogen-free stock. Methods are described for using fish cell cultures to detect IPN virus in peritoneal washes, feces, and gonadal fluids and thereby to identifiy carrier and non-carrier fish. The procedures were used to derive virus-free progeny from a hatchery trout population containing about one-third carrier fish. The progeny were reared to maturity, spawned for 3 successive years, and at each spawning they proved free of virus. Recommendations and precautions are given for those who may wish to apply the procedures.

Journal of the Fisheries Research Board of Canada↗
USGS1965

Characteristics and identification of oxidative Pseudomonads isolated from diseased fish

Several characteristics of 20 strains of oxidative pseudomonads, all but one of which were isolated from freshwater fish, were determined. All strains oxidized glucose and gluconate, produced NH 3 from 1 % peptone, grew at 6, 12, 20 and 30° and produced cytochrome oxidase. Lipase was produced by 17 of the strains, while 15 produced gelatinase, and 16 produced fluorescent pigment. These and other characteristics used to identify fish-spoilage pseudomonads are also useful for identification of fish-pathogenic pseudomonads. Species determinations from the present data were not attempted. However, from previously published data on speciation of Pseudomonas , most of the 20 strains appeared to be closely related to or identical with P. fluorescens .

Journal of General Microbiology↗
USGS1965

Characteristics and pathogenicity of a capsulated Pseudomonas isolated from goldfish

Characteristics of a capsulated bacterium isolated from an epizootic among goldfish ( Carassius auratus ) were determined as well as the ability of the bacterium to produce experimental infections. The bacterium was found to be a gram-negative rod which oxidized carbohydrates, produced green fluorescent pigment, and otherwise seemed to fit into the genus Pseudomonas , except that it was nonmotile and failed to oxidize gluconate. These last two characteristics are typical of pseudomonads. However, the bacterium was classified as a pseudomonad, best fitting the description of the nonmotile variety of Pseudomonas fluorescens . Goldfish and rainbow trout ( Salmo gairdneri ) were infected experimentally by injection, but not by being fed bacteria-laden food. Goldfish were infected by exposure to the bacterium, but only if two or three scales were removed prior to exposure. It is suggested that the bacterium is an opportunistic pathogen.

Applied Microbiology↗
USGS1964

Crystal formation in furunculosis agar

SINCE ITS INTRODUCTION SOME MONTHS AGO, FURUNCULOSIS AGAR has been employed in the diagnosis of suspect furunculosis and also as a general purpose medium. During our work with this medium we have noticed discrete "colonies," of crystalline material, which very closely resemble microbial colonies. These crystal colonies are compact and appear on both the surface and subsurface; they occur in inoculated slants and plates incubated for long periods (2 to 3 weeks), as well as in uninoculated stored medium. As the crystal colonies could be confusing to workers using this medium, we decided to attempt to identify them and also to determine whether storage conditions and different lots of medium affect crystal formation.

Progressive Fish-Culturist↗