Environmental factors affecting Edwardsiella ictaluri-induced mortality of riverine ayu, Plecoglossus altivelis (Temminck & Schlegel).
J Fish Dis
; 44(8): 1065-1074, 2021 Aug.
Article
em En
| MEDLINE
| ID: mdl-33755230
ABSTRACT
We analysed the predisposing factors for Edwardsiella ictaluri infection in the riverine ayu Plecoglossus altivelis on the basis of environmental and epidemiological data obtained in a tributary to and the lower reaches of the Tama River, Japan, in July and August 2011-2015. Mortality of ayu due to E. ictaluri infection was observed only in the tributary in August 2012 and 2013; both periods were unusually hot. During these mortality events, daily average water temperatures rose approximately 3-4°C over 4-8 days, reaching the optimum temperature for E. ictaluri infection (>25°C) and approaching the upper tolerable limit for ayu (30°C). Diurnal water temperature ranges (DWTRs) in the tributary during the mortality events exceeded 6°C, which was 1-2°C greater than in the lower reaches. Experimental infection of ayu with E. ictaluri resulted in higher mortality when exposed to 6°C DWTR than to 4°C DWTR. Furthermore, water levels in the tributary were generally low in August 2012 and 2013 because of low rainfall. From these results, we conclude that unusually high-water temperatures combined with high DWTRs and low water levels drove riverine ayu mortality from E. ictaluri infection.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Edwardsiella ictaluri
/
Osmeriformes
/
Infecções por Enterobacteriaceae
/
Doenças dos Peixes
/
Temperatura Alta
Limite:
Animals
País/Região como assunto:
Asia
Idioma:
En
Revista:
J Fish Dis
Assunto da revista:
BIOLOGIA
/
MEDICINA VETERINARIA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Japão