Yes bill several studies. Will post some more. The major problem it seems (may be in error) is occuring in hatchery purchased stock.


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Pleistophora ovarie infects golden shiner ovaries, reducing egg production. Egg masses appear discolored, opaque, yellow or brown instead of light green. Treatments for these diseases have not been developed and prevention requires culling of infected fish and disinfection of ponds. Pleistophora infections may be reduced by removing golden shiner females from brood fish ponds after two years of age.


http://aqfi.uaex.edu/grad/gradlife/thesis/pdf/proposal2.pdf

Ovipleistophora ovariae infects the ovaries and renders older fish sterile (Summerfelt 1994) forcing golden shiner farmers to use 1-year-old fish as breeders rather than more mature broodfish.

The presence of parasite spores in the ovary makes vertical transmission a likely mode.
Some researchers are confident that vertical transmission exists for O. ovariae, however they are unsure if it is transovarial (in the egg) or transovum (on the egg) (J. E. Smith, University of Leeds, personal communication).


Journal of Aquatic Animal Health
Volume 20, 2008 - Issue 1
Vertical Transmission of Ovipleistophora ovariae (Microspora) within the Eggs of the Golden Shiner
Nicholas B. D. Phelps
&
Andrew E. Goodwin
Pages 45-53 | Received 15 May 2007, Accepted 15 Sep 2007, Published online: 09 Jan 2011

Abstract
Fertilized eggs collected from broodfish infected by Ovipleistophora ovariae were tested by quantitative polymerase chain reaction (PCR) and found to be positive for the O. ovariae genome at 7.77 × 102 to 3.26 × 107 copies per microgram of host DNA. Fry hatched from these eggs contained from 1.37 × 102 to 9.89 × 106 copies of the O. ovariae genome per microgram of host DNA. Surface treatments of fertilized eggs with 150 mg formalin/L (used by farms as a fungicide) or a 1.5% solution of sodium sulfite (which removes the adhesive egg matrix) did not reduce vertical transmission to fry. Treatment of eggs with a 10% solution of bleach or a proprietary commercial DNA denaturant did not reduce the number of egg-associated copies of the O. ovariae genome. Histology of ovaries of infected fish demonstrated spores within the oocytes. However, no spores were observed by histology in positive fry hatched from infected eggs. The PCR and histological demonstration of the presence of O. ovariae spores in oocytes and fry, and the failure of strong DNA denaturants to reduce egg-associated copies, give evidence that O. ovariae is vertically transmitted within eggs.

Transboundary and Emerging Diseases
An expert-based risk ranking framework for assessing potential pathogens in the live baitfish trade
Margaret C. McEachran,Fernando Sampedro,Dominic A. Travis,Nicholas B. D. Phelps
First published: 09 December 2020

https://doi.org/10.1111/tbed.13951
Citations: 1

Ovipleistophora ovariae is an obligate intracellular and vertically transmitted parasite, infecting the ovarian tissue of golden shiners, leading to significant declines in fecundity by age-2 (Phelps & Goodwin, 2008). Although O. ovariae is believed to be widely distributed and highly prevalent in the golden shiner supply chain, surveys of wild populations to confirm establishment have not been completed (McEachran et al., accepted), and the parasite remains of concern. Indeed, a previous qualitative risk assessment for golden shiners imported from Arkansas bait producers identified both Asian fish tapeworm and O. ovariae as high-risk

Last edited by ewest; 10/25/22 10:32 AM.