Spironucleus spp. and experimental spironucleosis in salmonids
Bibliographic record
Abstract
The hexamitid causing systemic infection and mortality in sea-caged ' Oncorhynchus tshawytscha' in Canada is confirmed to be a ' Spironucleus'. It is different from 'Spironucleus barkhanus ' that causes systemic infection in 'Salmo salar' in Norway, and is therefore described as a new species, 'Spironucleus kenti' n. sp. 'Spironucleus kenti' n. sp. is significantly shorter than ' S. barkhanus.' It infects 'O. tshawytscha, Oncorhynchus kisutch, Oncorhynchus mykiss' and 'S. salar', while ' S. barkhanus' only infects 'S. salar. Spironucleus kenti' n. sp. is lysed in fresh plasma ('in vitro') from refractive ' S. salar', while 'S. barkhanus' is lysed in fresh plasma from refractive fishes. 'Spironucleus kenti' n. sp. causes high blood parasitaemia in 'O. tshawytscha', whereas the parasitaemia of 'S. barkhanus' is low in 'S. salar. Spironucleus kenti' n. sp. requires fish plasma supplement for prolonged ' in vitro' culture and it also differs in polypeptide and antigenic profiles from 'S. barkhanus'. Agglutinating antibodies from recovered 'O. tshawytscha' have 16 times higher titres to ' S. kenti' n. sp. than to 'S. barkhanus', while those from recovered 'S. salar' have 32 times higher titres to ' S. barkhanus' than to 'S. kenti' n. sp. Complement fixing antibodies from recovered 'O. tshawytscha' do not fix complement to lyse 'S. barkhanus' and those from recovered ' S. salar' do not cross react with 'S. kenti' n. sp. These differences indicate there are two species of 'Spironucleus' in salmonids. Both 'Spironucleus' spp. can be cultured in Trypticase-Yeast extract-Iron medium without bile supplement. The multiplication of ' S. kenti' n. sp. starts with duplications of the nuclei and cytostomal canals, and is completed with longitudinal division after one set of nuclei has migrated to the opposite end. The mechanism of innate immunity in refractive fishes is lysis of parasite via the alternative complement pathway. Recovered fish are protected, and both humoral and cell mediated immunity are involved in protection. The mechanisms include leucocyte activation, productions of heat shock protein, agglutinating and complement fixing antibodies (lyse parasite via the classical complement pathway), and antibody-dependent and antibody-independent cell mediated cytotoxicity.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".