title: A study of gross, histological and blood biochemical changes in rainbow trout, Oncorhynchus mykiss (Walbaum), with rainbow trout gastroenteritis (RTGE).
abstract: The mechanisms behind the pathogenesis of rainbow trout gastroenteritis (RTGE) are still unknown. This study examined the macroscopic and microscopic changes in trout with RTGE (RTGE+), as well as the blood chemistry. A total of 464 rainbow trout were sampled from 11 sites in the UK, comprising 152 RTGE+ fish and 330 random, apparently healthy fish. A case definition for RTGE was assessed by the analysis of its agreement with three laboratory tests: histopathology, packed cell volume and kidney bacteriology. Cluster analysis indicated the presence of three distinct presentations within the population of RTGE+ fish. Cluster A included gross signs associated with moribund RTGE+ fish, and clusters B and C identified gross signs consistent with concurrent diseases, notably furunculosis, enteric redmouth and proliferative kidney disease. The information gained was used to select RTGE+ fish without concurrent disease for the analysis of RTGE pathogenesis with blood biochemistry. This analysis revealed a severe osmotic imbalance and a reduced albumin/globulin ratio as indicatives of selective loss of albumin. These findings are compatible with a protein losing enteropathy.
authors.affiliation: Institute of Aquaculture, University of Stirling, Stirling, UK. londig@hotmail.com
authors.forename: J
authors.initials: J
authors.lastname: Del-Pozo
authors.forename: J F
authors.initials: JF
authors.lastname: Turnbull
authors.forename: M
authors.initials: M
authors.lastname: Crumlish
authors.forename: H W
authors.initials: HW
authors.lastname: Ferguson
mesh_terms: D000818:Animals; D001774:Blood Chemical Analysis; D001824:Body Constitution / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D016000:Cluster Analysis; D003955:Diagnostic Tests, Routine / Q000662:veterinary; D005393:Fish Diseases / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology; D005759:Gastroenteritis / Q000175:diagnosis / Q000473:pathology / Q000503:physiopathology / Q000662:veterinary*; D017686:Oncorhynchus mykiss; D012680:Sensitivity and Specificity