Premium
Efficacy of Chloramine‐T to Control Mortality in Freshwater‐Reared Salmonids Diagnosed with Bacterial Gill Disease
Author(s) -
Bowker James D.,
Carty Daniel G.,
Telles Larry,
David Bob,
Oviedo David
Publication year - 2008
Publication title -
north american journal of aquaculture
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.432
H-Index - 41
eISSN - 1548-8454
pISSN - 1522-2055
DOI - 10.1577/a06-042.1
Subject(s) - rainbow trout , biology , hatchery , aquaculture , trout , fishery , fish mortality , fish <actinopterygii> , freshwater fish , zoology
Bacterial gill disease (BGD), caused by Flavobacterium branchiophilum and other species of yellow‐pigmented, filamentous bacteria, is a common and potentially catastrophic disease of hatchery (freshwater)‐reared fish. Chloramine‐T (Chl‐T) is a biocide proven effective for controlling mortality in freshwater‐reared fish diagnosed with BGD. However, Chl‐T is not approved by the U.S. Food and Drug Administration for such use. To generate data in support of a U.S. approval, we evaluated the effectiveness of Chl‐T (administered at 12 mg/L of static bath water for 60 min/d on three alternate days) to control mortality caused by BGD in freshwater‐reared chum salmon Oncorhynchus keta , Apache trout O. gilae apache , and rainbow trout O. mykiss . For each species, the mean percent total mortality in Chl‐T‐treated tanks ( N = 3) was significantly less than that in control tanks ( N = 3): Chum salmon = 8.9% versus 99.7%, Apache trout = 39.2% versus 97.9%, and rainbow trout = 5.7% versus 25.8%. Because the Chl‐T treatment regimen was efficacious for each species, we conclude that our findings support the approval of Chl‐T for use in the USA to control mortality in freshwater‐reared salmonids diagnosed with BGD.