Oomycete parasites in freshwater copepods of Patagonia: effects on survival and recruitment.
Dis Aquat Organ
; 129(2): 123-134, 2018 Jul 04.
Article
em En
| MEDLINE
| ID: mdl-29972373
ABSTRACT
Copepods are hosts to various oomycete parasite species, but the effects of pathogens on copepod populations have rarely been studied. This study aimed to characterize oomycete infection in the freshwater copepod Parabroteas sarsi in a temporary pond in Patagonia (Argentina). A complete hydroperiod was monitored, evaluating environmental variables as influencing factors in the oomycete infections. Laboratory experiments were performed to evaluate the susceptibility of infected copepods to consumption by predators. Although 5 species of copepods were present in the pond, only ovigerous P. sarsi females were parasitized by oomycetes. Two species of oomycetes were always found together Aphanomyces ovidestruens and Pythium flevoense. Infections were detected at water temperatures >20°C, with a positive relationship between temperature and parasite prevalence. Infection occurred after a decrease in large filter-feeder densities. The pathogens were not lethal to P. sarsi females in the short-term, but did produce mortality of entire egg sacs, thus negatively impacting subsequent recruitment. Mean prevalence of infection in females was 53%, reaching 83% in December. Females have the capacity to release an infected egg sac and generate a new one in a few days. This infection does not affect the susceptibility of P. sarsi to the predator Notonecta vereertbruggheni. The decrease in female abundance registered towards the end of the hydroperiod could be related to a combination of factors that may have a differential effect on female survival, such as increasing temperature, the energy cost of egg sac development and carrying and oomycete infection.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Oomicetos
/
Copépodes
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
País/Região como assunto:
America do sul
/
Argentina
Idioma:
En
Revista:
Dis Aquat Organ
Assunto da revista:
BIOLOGIA
/
MEDICINA VETERINARIA
/
MICROBIOLOGIA
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Argentina