Parasite transmission through suspension feeding

Abstract

Suspension-feeding bivalve molluscs are confronted with a wide range of materials in the benthic marine environment. These materials include various sized plankton and the organic material derived from it, macroalgae, detritus and a diversity of microbial parasites that have adapted life stages to survive in the water column. For bivalve parasites to infect hosts though, they must first survive and remain infectious in the water column to make initial contact with hosts, and once in contact, enter and overcome elaborate pathways for particle sorting and selection. Even past these defenses, bivalve parasites are challenged with efficient systems of mechanical and chemical digestion and highly evolved systems of innate immunity. Here we review how bivalve parasites evade these hurdles to complete their life cycles and establish within bivalve hosts. We broadly cover significant viral, bacterial, and protozoan parasites of marine bivalve molluscs, and illustrate the emergent properties of these host-parasite systems where parasite transmission occurs through suspension feeding.

Potential trade-offs between biomineralization and immunity revealed by shell properties and gene expression profiles of two closely related Crassostrea species

“…Like many benthic sessile species, oysters have a limited ability to escape environmental stressors or predators and rely on mechanical protection ( provided by their shells) (Kocot et al, 2016) and physiological and biochemical adjustments (Sokolova et al, 2011) to survive predator attacks and/or shifts in the environmental conditions. Furthermore, because of their filterfeeding habit, oysters are exposed to a large amount and diversity of parasites and pathogens, with an average oyster encountering tens to hundreds of thousands of microbes per second (Allam and Pales Espinosa, 2016;Ben-Horin et al, 2015). In past decades, oyster diseases have expanded in range and increased in severity, often causing staggering losses in the impacted species (Barbosa Solomieu et al, 2015;Beck et al, 2011;Ford and Smolowitz, 2007;Ford, 1996).…”

The Utilization of Native Freshwater Mussel <i>Pilsbryoconcha exilis</i> as Biocontrol of Pathogenic Bacteria <i>Aeromonas hydrophila</i> in Tilapia Aquaculture

“…The ecological services by filter feeder animals in the aquaculture system indeed may have either benefits or adverse impacts to the production i.e. by improving water quality (Brown et al 2011, Chopin et al 2001, Joyni et al 2011 and entrap the swarming pathogen in water column (Molloy et al 2011, Rolin et al 2016, Webb et al 2013 or may also be detriment to the farm biosecurity by accumulating the pathogen and transmitting the pathogen from one species to another (McConnachie et al 2013, Ben-Horin et al 2015, Desrina et al 2013. In this context, the fate of the infection may depend on the particle selectivity of bivalve, the degree of infectivity of pathogens, the transmission mechanism of the pathogen, and the ability of pathogens to resist degradation in the gut of bivalve (Burge et al 2016).…”

Unusually abundant and large ciliate xenomas in oysters, Crassostrea virginica , from Great Bay, New Hampshire, USA

“…Oysters are filter-feeding organisms, which exposes them to invasion by a wide variety and large number of potential pathogens (Ben-Horin et al, 2015). This study produced significant information about the highly prevalent and unusually large intracellular parasite colonies, or xenomas, in oysters from Great Bay, New Hampshire, USA.…”