DOI: 10.5061/dryad.wwpzgmswq
title: Data from: Laboratory transmission of Adult Salmon Enteritis and associated pathogens in juvenile chinook salmon (<em>Oncorhynchus tshawytscha</em>)

description: Adult Salmon Enteritis (ASE), characterized by severe ulcerative
 enteritis, has been linked to pre-spawn mortality (PSM) in spring Chinook
 Salmon (Oncorhynchus tshawytscha) in certain rivers in Oregon, USA.
 Catastrophic losses of spring Chinook Salmon have resulted from PSM, a
 significant threat to their population stability. Understanding the causes
 of ASE is therefore critical for mitigating PSM and supporting
 conservation. This study investigates the potential infectious etiology of
 ASE using a juvenile Chinook Salmon model. Fish were immunocompromised
 with dexamethasone implants, fasted, and exposed to intestinal tissues
 from ASE-affected adult Chinook. Histopathology of the recipient fish
 revealed mid-intestinal lesions consistent with ASE. The microsporidium
 Enterocytozoon schreckii, which is observed in ASE-affected adults from
 rivers, was transmitted for the first time to juvenile Chinook Salmon,
 making E. schreckii a potential new pathogen of juvenile salmon.
 Additionally, intranuclear inclusions were identified in enterocytes by
 histopathology, and viral particles were detected by electron microscopy
 in recipient fish. The study demonstrates that intestinal lesions
 consistent with ASE can be experimentally induced in juvenile Chinook
 Salmon through oral exposure to infected tissues, supporting an infectious
 etiology. Further research is needed to isolate specific pathogens,
 including viruses and E. schreckii, and to elucidate their roles in ASE
 development.
description: # Data from: Laboratory transmission of Adult Salmon Enteritis and
 associated pathogens in juvenile chinook salmon (*Oncorhynchus
 tshawytscha*) Dataset DOI:
 [10.5061/dryad.wwpzgmswq](10.5061/dryad.wwpzgmswq) ## Description of the
 data and file structure Phase 1 Histo: Histology data from the Phase 1
 section of our experiment.  Phase 2 Histo: Histology data from the Phase 2
 section of our experiment.  Phase 1 Mortality: Mortality data over time
 from the Phase 1 section of our experiment.  Phase 2 Mortality: Mortality
 data over time from the Phase 2 section of our experiment.  Any na
 represent missing data ### Files and variables #### File: phase1_histo.csv
 **Description:** Phase 1 experimental section for choosing appropriate
 dexamethasone and fasting regimes to use for the Phase 2 section.  #####
 Variables * fish_id: Individual fish ID numbers. * month: Time the fish
 were collected (Month 1 [24 days] or Month 2 [50 days]) * Tank: Tank the
 fis the tankh were placed in.  * treatment: Dexamethasone (HighDose,
 LowDose, Control) and/or Fasting (HighFast, LowFast, Control) treatments. 
 * sex: Female (F) or Male (M) or Unknown (U).  * enteritis: Histologic
 score (0,-3; normal, mild moderate, severe) * villar_folds: Histologic
 score (0-3; normal, mild moderate, severe) * hepatic_vacuoles: Histologic
 score (0-3; normal, mild moderate, severe) * kidney_melanin: Histologic
 score (0-3; normal, mild moderate, severe) * coelomitis: Histologic score
 (0-3; normal, mild moderate, severe) * branchitis: Histologic score ,(0-3;
 normal, mild moderate, severe) * Myositis: Histologic score (0-3; normal,
 mild moderate, severe) #### File: phase1_mortality.csv
 **Description:** Mortality data over time of the Phase 1 experiment, where
 individual fish were given ID numbers and tracked over time.  #####
 Variables * Fish: ID number * Day: Day during the experimental period
 (0-50).  * Event: Survival (0) or mortality (1).  * Dex_treatment:
 Dexamethasone treatment group (HighDose, LowDose, or CThe fish was in the
 tank the fish was in.  * Diet_treatment: Diet treatment group (HighFast,
 LowFast, or Control).  #### File: phase2_histo.csv **Description:** Phase
 2 experiment where fish were subjected to different groups: DexFast Only,
 ASE Only, DexFast + ASE, and Control groups. Dex = dexamethasone
 treatment. Fast = fasting diet. ASE = oral gavage exposure to intestinal
 tissues from adult salmon affected by adult salmon enteritis (ASE).  #####
 Variables * fish-id: Individual fish ID. * month: Time the fish were
 collected (Month 1 [24 days] or Month 2 [50 days]) * Tank: Tank the fis
 the tankh were placed in.  * treatment: DexFast Only, ASE Only, DexFast +
 ASE, and Control groups (see Description).  * sex: Male (M), Female (F),
 or Unknown (U). * weight: Whole body weight at experiment termination (50
 days) in grams.  * es: *Enterocytozoon schreckii* detection by H&E
 stain.  * es-luna: *Enterocytozoon schreckii* detection by Luna stain.  *
 enteritis: Histologic score (0,-3; normal, mild moderate, severe) *
 dysplasia: Histologic score (0-3; normal, mild moderate, severe) *
 int-folds: Histologic score ,(0-3; normal, mild moderate, severe) *
 hep-vacuolation: Histologic score, (0-3; normal, mild moderate, severe) *
 kidney-melanin: Histologic score (0-3; normal, mild moderate, severe) *
 coelomitis: Histologic score, re (0-3; normal, mild moderate, severe) *
 Myositis: Histologic score (0, 3; normal, mild moderate, severe) ####
 File: phase2_mortality.csv **Description:** Mortality data over time of
 the Phase 2 experiment section, where individual fish were given ID
 numbers and tracked over time.  ##### Variables * Fish: ID number * Day:
 Day during the experimental period (0-50).  * Event: Survival (0) or
 mortality (1).  * Tank: Tank identification.  * Treatment: Treatment group
 (DexFast Only, ASE Only, DexFast + ASE, and Control). ## Code/software
 Microsoft Excel was used to visualize the .csv files, although other
 options are available to view this file type.  ## Access information All
 data was generated by this research experiment and is not available
 anywhere else.