Large-scale infection of the ascidian Ciona intestinalis by the gregarine Lankesteria ascidiae in an inland culture system

Abstract

An important way to keep transgenic and mutant lines of the ascidian Ciona intestinalis, a model system for e.g. genetic functions, in laboratories is via culturing systems. Here we report a disease of C. intestinalis observed in an inland culturing system. The disease, called 'long feces syndrome,' is expressed in affected animals by the following characteristic symptoms of the digestive system: (1) excretion of long and thin feces, (2) pale color of the stomach, and (3) congestion of the digestive tube by digested material. Severely diseased animals usually die within a week after the first symptoms occur, implying a high risk of this disease for ascidian culturing systems. The digestive tubes of the diseased animals are occupied by the gregarine apicomplexan parasite Lankesteria ascidiae, suggesting that large-scale infection by this parasite is the cause of long feces syndrome.

Long‐term demographic and reproductive trends in Ciona intestinalis sp. A

“…; Mita et al . ). Thus laboratory research is strongly dependent upon sampling and maintenance of wild specimens.…”

“…Worldwide distribution of C. intestinalis is widening through invasions along the coasts of the USA, Chile, Western Australia, New Zealand, Canada and South Africa (Millar 1966;McDonald 2004;Blum et al 2007;Ramsay et al 2008Ramsay et al , 2009Dumont et al 2011), where the alteration of the sessile community composition and the depression of species diversity sometimes has a severe ecological and economic impact on the local biota (Blum et al 2007;Therriault & Herborg 2008). Although the growing genetic and genomic toolkit has prompted interest in this species (Dehal et al 2002;Delsuc et al 2006;Kano et al 2006;Lemaire et al 2008;Cutter & Agrawal 2010;Matsumoto et al 2010;Ferrier 2011;Satou et al 2012;Tsagkogeorga et al 2012), C. intestinalis culturing is not straightforward (Cirino et al 2002;Joly et al 2007;Mita et al 2012). Thus laboratory research is strongly dependent upon sampling and maintenance of wild specimens.…”

The Symbiotic Spectrum: Where Do the Gregarines Fit?

“…Gregarine infections are generally considered benign, unless the numbers of gregarines become large enough to impede passage of food through the host's gut [27,28]. Several reports have discussed potential negative effects of the presence of gregarines in host organisms, including reduced longevity and growth, increased mortality, and nutrient deficiency (see Table S1 in the supplemental information online).…”

“…Several reports have discussed potential negative effects of the presence of gregarines in host organisms, including reduced longevity and growth, increased mortality, and nutrient deficiency (see Table S1 in the supplemental information online). Most of these reports are focused on terrestrial invertebrates, while hardly anything is known about aquatic invertebrates except for some ascidians [28], bivalves such as oysters [29], or scallops [30] and crustaceans [14]. The effects range from high mortalities in ascidians [28] to negligible effects in bivalves [30].…”

“…Most of these reports are focused on terrestrial invertebrates, while hardly anything is known about aquatic invertebrates except for some ascidians [28], bivalves such as oysters [29], or scallops [30] and crustaceans [14]. The effects range from high mortalities in ascidians [28] to negligible effects in bivalves [30]. In vitro experiments in insects have suggested that the number of gregarines can affect, for example, the overall flight performance and mating success of dragonflies [31], increase adult mortality and inhibit ovarian and fat body development in the western corn rootworm [32], mortality of immature sand fly stages and a negative effect on the survival of adult males and females [33].…”