Controlling Endemic Pathogens—Challenges and Opportunities

Abstract

By most measures, the University of Utah Centralized Zebrafish Animal Resource is a successful zebrafish core facility: we house ∼4000-5000 tanks for over 16 research groups; provide services and equipment for ∼150 users; are currently undergoing an expansion by 3000 tanks; and have been praised by institutional and national regulatory agencies for the cleanliness and efficiency of our facility. In recent years, we have implemented new programs to improve the overall health of our colony and believe we have seen a reduction in apparently sick fish. However, there are still deficiencies in our monitoring and pathogen control programs. Our histopathology sample sizes have been insufficient to estimate prevalence, but our sentinel tank program reveals the presence of Pseudoloma neurophilia and myxozoan, presumably Myxidium streisinger, in our facility. As we develop protocols to further reduce the burden of disease, we are focused on defining our baseline, establishing goals, and implementing methods to monitor our progress. The data generated by this approach will allow us to evaluate and implement the most cost-effective protocols to improve fish health.

Universal Healthcare for Zebrafish

“…Articles by Geisler et 7,8,12,13,23 Several articles also point out how simple strategies, for example, using brightly colored markers or different room colors, can simplify monitoring by making health status of particular fish available at a glance. 5,15,16 The articles in this issue and the results of our survey reveal that most facilities have quarantine space so that zebrafish imported from other facilities are monitored before being moved into main facility housing. This is important to prevent spread of disease between facilities.…”

“…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.…”

“…6,7,[9][10][11]13 Larger facilities or those that aspire to be specifically pathogen free may consider more elaborate, multistage quarantine that can afford increased health surveillance opportunities and thus contribute to improved health monitoring that will benefit not only those facilities but also the community at large. 5,8,15,16 Surface disinfection of fish embryos, typically by sodium hypochlorite (bleach), [32][33][34] is another essential component of fish health management. Surveys indicate a bewildering number of variations of bleaching protocols, many of which vary in dosage and exposure times.…”

Intranuclear inclusions consistent with a Nucleospora sp. in a lymphoid lesion in a laboratory zebrafish, Danio rerio (Hamilton 1822)

“…Zebrafish ( Danio rerio ) were maintained in accordance with approved institutional protocols under the supervision of the Institutional Animal Care and Use Committee (IACUC) of the University of Utah, which is fully accredited by the AAALAC. Description of this facility and health and biosecurity protocols are described by Hobbs, Shankaran, and James (2016). This facility is typical of a large, centralized facility with recirculating systems.…”

“…The facility has five separate recirculating systems, but fish are interchanged between systems. Water system parameters are standard for zebrafish in laboratories (Cockington, 2020; Hobbs et al., 2016, Hammer 2020). Water in tanks are maintained at approximately 28°C, 550 µS/cm conductivity and at pH 7.2.…”