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Aaron Johnson

Publications and source records attributed to Aaron Johnson.

2 recordsLinked to original sources

Living with wildfire in Montrose County, Colorado: 2023 Data report

During 2022–2024, the Wildfire Research (WiRē) Center partnered with the West Region Wildfire Council (WRWC) to learn more about parcel-level wildfire risk in Montrose County, Colorado. This research project was part of a larger, sustained collaboration between WiRē and the WRWC, moving the focus from areas typically characterized as fire-prone due to heavily treed and steep topography, into an area with relatively gentle topography and lighter fuels. The study area borders and includes northern portions of Ouray County that fall within the service area of Montrose County Fire Protection District. The area was of particular interest to the WRWC because it lacks some of the social infrastructure typically leveraged to build community relationships, such as Homeowners Associations, and the WRWC sought to build understanding in order to provide a foundation to foster stronger ties to pursue wildfire risk reduction. The study also presented an opportunity to help assess interest in the WRWC’s cost share program intended to facilitate risk mitigation action on private properties.

Colorado

Efficacy of florfenicol and oxytetracycline administered in feed to control cisco mortality associated with Aeromonas salmonicida infections

Two medications (one with florfenicol and one with oxytetracycline) that are approved in the United States to control mortality due to furunculosis associated with Aeromonas salmonicida were assessed to determine their efficacy in medicated feeds to treat A. salmonicida -infected Cisco (also known as Lake Herring) Coregonus artedi . Cisco were subjected to static infection baths containing A. salmonicida or a sham control and then were distributed to replicate test tanks within four treatment groups: (1) fish infected with A. salmonicida and treated with 15 mg florfenicol·kg body weight (BW) −1 ·d −1 , (2) fish infected with A. salmonicida and treated with 83 mg oxytetracycline·kg BW −1 ·d −1 , (3) fish infected with A. salmonicida and treated with a nonmedicated control feed, and (4) uninfected fish treated with a nonmedicated control feed. Medicated and comparative nonmedicated feed rations were administered at 2% BW/d for 10 consecutive days in accordance with the U.S. Food and Drug Administration-approved drug label, followed by a 7-d postdosing observation period using only nonmedicated feed. Cisco that were infected with A. salmonicida and treated with florfenicol (79% survival) and oxytetracycline (85% survival) had significantly higher survival than A. salmonicida -infected fish that received no medicated treatment (3% survival). No statistical difference in Cisco survival between the two medicated feed types was found. Aeromonas salmonicida was not detected in the kidney tissue of any surviving fish treated with medicated feeds at 7 d postdosing using quantitative PCR analysis. Overall, this study demonstrated that florfenicol- and oxytetracycline-medicated feeds were effective A. salmonicida treatments for Cisco. Outcomes may inform ongoing propagation efforts for Cisco restoration within the Great Lakes basin.

North American Journal of Aquaculture