Expansion of the Known Host Range of the Microsporidium, Pseudoloma neurophilia

Abstract

The microsporidium, Pseudoloma neurophilia, is the most common infectious organism found in laboratory zebrafish colonies. Many currently used zebrafish lines originally came from pet store fish, and the initial description of P. neurophilia came from zebrafish obtained from a retail pet store. However, as P. neurophilia has not been described from wild-caught zebrafish, whether P. neurophilia is a natural pathogen of zebrafish is an open question. The pooling of fish of different species in the aquarium fish trade is common and a generalist parasite could be transmitted to novel hosts in this scenario. We determined that P. neurophilia can infect seven species of fishes from five families by cohabitation with infected zebrafish: Betta splendens, Xiphophorus maculatus, Devario aequipinnatus, Pimephales promelas, Oryzias latipes, Carassius auratus and Paracheirodon innesi. Infections in these fishes were histologically similar to those of zebrafish. We include a case report of a laboratory population of fathead minnows with naturally acquired P. neurophilia infections. With such a broad host range, including several fish families, other laboratory fishes should be screened routinely for this and other microsporidian parasites.

Reviewing Pseudoloma neurophilia infections in the popular zebrafish model

“…Importantly, this parasite is mostly unique for zebrafish species. Nevertheless, under experimental conditions, P. neurophilia is also capable of infecting seven species of fish from five families by cohabitation with infected zebrafish: siamese fighting fish (Betta splendens Regan 1910), southern platyfish (Xiphophorus maculatus (G€ unther 1866)), giant danio (Devario aequipinnatus (McClelland 1839)), fathead minnow (Pimephales promelas (Rafinesque 1820)), medaka (Oryzias latipes (Temminck & Schlegel 1846)), goldfish (Carassius auratus (Linnaeus 1758)) and neon tetra (Paracheirodon innesi (Myers 1936)) (Sanders et al 2016). Also naturally acquired P. neurophilia infections were recorded in a laboratory population of P. promelas (Sanders et al 2016).…”

“…Many aspects of P. neurophilia infections are still not well understood; thus, no effective treatment to abolish the infection has been developed yet. In fact, there are unsolved questions, such as the debate about whether P. neurophilia is a natural pathogen of zebrafish (Sanders et al 2016).…”

Multi-state occupancy model estimates probability of detection of an aquatic parasite using environmental DNA: Pseudoloma neurophilia in zebrafish aquaria

“…This parasite continues to be prevalent in zebrafish research facilities that report to the diagnostic service of the Zebrafish International Resource Center (ZIRC) in Eugene, Oregon (Murray et al 2011, Kent et al 2020a). P. neurophilia is an obligate intracellular parasite that causes chronic infections in zebrafish and infects a broad range of fishes (Sanders et al 2016). Infections by P. neurophilia are largely asymptomatic.…”

Universal Healthcare for Zebrafish

“…It is both a celebration of the extraordinary growth of the model and an initiation of a discussion on ways to capitalize on what has been learned about zebrafish husbandry and health so that zebrafish can continue to be an outstanding model, whether one has a single small tank or a gigantic facility. This collection of 23 articles submitted by contributors from around the world addresses a wide range of issues ranging from management of many types and sizes of zebrafish research facilities, [5][6][7][8][9][10] strategies for monitoring colony health, [11][12][13][14] case reports of pathogen outbreaks in zebrafish colonies, 15,16 results of studies of endemic and exotic pathogens, [17][18][19] testing of disinfection protocols, 20 establishing regulations for health surveillance for zebrafish importation, 21 to standardization of reporting on health status, 8,[22][23][24] nomenclature, 25 and nutrition. 26 We view this as the beginning of a community-wide dialogue that will promote zebrafish health and thus enhance research productivity and validity of results.…”

“…For example, fish pathogens from the hobbyist trade can spread to other species, including zebrafish. 19 Although quarantine is important, quarantine space comes in many different configurations, ranging from a single rack within a facility, to a separate room within a facility, to a room or set of rooms that are completely separated from the main housing area. A commonality among all of the different quarantine arrangements is to further the aim of ensuring that both zebrafish and personnel within a facility are protected from pathogens that may be carried by imported fish.…”