Detailed Research Information

Detailed project information for
Study Plan Number 01072-05

Branch : Fish Health Branch

Study Plan Number : 01072-05

Study Title : Further investigations on the nature of vertical transmission of Aeromonas salmonicida

Starting Date : 10/01/1996

Completion Date : 09/30/1999

Principal Investigator(s) : Cipriano, Rocco C.

Primary PI : Cipriano, Rocco C.

Telephone Number : (304) 724-4432

Email Address : rocco_cipriano@usgs.gov

SIS Number : 5002165

Primary Program Element : Fisheries and Aquatic Resources

Second Program Element : Application of Science Information to Management

Status : Completed

Abstract : The U.S. Fish and Wildlife Service federal protocol for dual disinfection of fish eggs in 50-mg/L of iodine for 30 minutes followed by a secondary disinfection in 100-mg/L iodine for 10 minutes was investigated during six spawning cycles of Atlantic salmon (Salmo salar) held at the Richard Cronin National Salmon Station (Sunderland, MA). This population of salmon had undergone an epizootic of furunculosis and the surviving fish maintained a persistent infection of A. salmonicida throughout the course of study. Eggs from twenty individual paired-matings of salmon were annually obtained during the first two weeks of November in each spawning cycle from 1995 through 2000, except for 1999 when fertilized eggs from 35 pairs of salmon were examined. Aeromonas salmonicida was isolated from 19 of 135 total groups of fertilized eggs that were investigated throughout the duration of this study. In these cases, all isolations of the pathogen were made only in fertilized eggs before any disinfection in iodophor had occurred. In contrast to the results produced in the field, in vitro assays actually showed that A. salmonicida was not completely killed when initial concentrations of the bacterium ranged between 1.0x107 to 1.2x108 cfu of bacteria per mL. However, even when bacterial concentrations exceeded 1.0x107 cfu/mL no A. salmonicida remained viable if treated first with 50-mg/L iodine for 30 minutes and then with 100- mg/L iodine for 10 minutes, as prescribed in federal policy. Results of the current analysis also provided further evidence that A. salmonicida is not transmitted vertically via intra-ovum infection.

For More Information :

° Home

U.S. Department of the Interior || U.S. Geological Survey
11700 Leetown Road, Kearneysville, WV 25430, USA
URL: http://www.lsc.usgs.gov
Maintainer: lsc_webmaster@usgs.gov
Last Modified: October 21, 2002 dwn
Privacy Policy and Disclaimers || FOIA || Accessibility

Branch :	Fish Health Branch
Study Plan Number :	01072-05
Study Title :	Further investigations on the nature of vertical transmission of Aeromonas salmonicida
Starting Date :	10/01/1996
Completion Date :	09/30/1999
Principal Investigator(s) :	Cipriano, Rocco C.
Primary PI :	Cipriano, Rocco C.
Telephone Number :	(304) 724-4432
Email Address :	rocco_cipriano@usgs.gov
SIS Number :	5002165
Primary Program Element :	Fisheries and Aquatic Resources
Second Program Element :	Application of Science Information to Management
Status :	Completed
Abstract :	The U.S. Fish and Wildlife Service federal protocol for dual disinfection of fish eggs in 50-mg/L of iodine for 30 minutes followed by a secondary disinfection in 100-mg/L iodine for 10 minutes was investigated during six spawning cycles of Atlantic salmon (Salmo salar) held at the Richard Cronin National Salmon Station (Sunderland, MA). This population of salmon had undergone an epizootic of furunculosis and the surviving fish maintained a persistent infection of A. salmonicida throughout the course of study. Eggs from twenty individual paired-matings of salmon were annually obtained during the first two weeks of November in each spawning cycle from 1995 through 2000, except for 1999 when fertilized eggs from 35 pairs of salmon were examined. Aeromonas salmonicida was isolated from 19 of 135 total groups of fertilized eggs that were investigated throughout the duration of this study. In these cases, all isolations of the pathogen were made only in fertilized eggs before any disinfection in iodophor had occurred. In contrast to the results produced in the field, in vitro assays actually showed that A. salmonicida was not completely killed when initial concentrations of the bacterium ranged between 1.0x107 to 1.2x108 cfu of bacteria per mL. However, even when bacterial concentrations exceeded 1.0x107 cfu/mL no A. salmonicida remained viable if treated first with 50-mg/L iodine for 30 minutes and then with 100- mg/L iodine for 10 minutes, as prescribed in federal policy. Results of the current analysis also provided further evidence that A. salmonicida is not transmitted vertically via intra-ovum infection.
For More Information :
° Home


U.S. Department of the Interior \|\| U.S. Geological Survey 11700 Leetown Road, Kearneysville, WV 25430, USA URL: http://www.lsc.usgs.gov Maintainer: lsc_webmaster@usgs.gov Last Modified: October 21, 2002 dwn Privacy Policy and Disclaimers \|\| FOIA \|\| Accessibility