Inter-Research > DAO > v129 > n2 > p123-134  
Diseases of Aquatic Organisms

via Mailchimp

DAO 129:123-134 (2018)  -  DOI:

Oomycete parasites in freshwater copepods of Patagonia: effects on survival and recruitment

Roberto Daniel Garcia1,*, Fabián Gastón Jara1, Mónica Mirta Steciow2, Mariana Reissig1,3

1INIBIOMA (UNComahue-CONICET), S. C. de Bariloche 8400, Argentina
2Instituto de Botánica Spegazzini-Facultad De Ciencias Naturales y Museo-UNLP, La Plata 4198, Argentina
3Universidad Nacional del Comahue, S. C. de Bariloche 8400, Argentina
*Corresponding author:

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.

KEY WORDS: Parasitism · Oomycete · Copepoda · Life cycle · Planktonic predator · Patagonia

Full text in pdf format
Cite this article as: Garcia RD, Jara FG, Steciow MM, Reissig M (2018) Oomycete parasites in freshwater copepods of Patagonia: effects on survival and recruitment. Dis Aquat Org 129:123-134.

Export citation
Share:    Facebook - - linkedIn

 Previous article Next article