Identification of Myxozoa Parasite in the Connective Tissue of a Cascadura Fish (Hoplosternum Littorale) In Trinidad and Tobago

Background: Thirty cascadura (Hoplosternum littorale) fish from 5 different ponds were submitted alive to the Aquatic Animal Health Laboratory of the School of Veterinary Medicine, University of West Indies as part of monitoring and quarantine procedures of a commercial aquaculture farm. Cascadura fish are commercially important in Trinidad. Methodology: Water from the five different ponds was tested for quality. All fish were euthanized and necropsies were performed. Pooled samples from each pond were submitted for microbiology, parasitology, and histopathology. Results: All water samples had low alkalinity, low hardness, and low pH. In general, all ponds had evidence of low to moderate ecto- and endoparasitism. A section of connective tissue from the histopathologic samples of the pond with the lowest pH contained an area of hemorrhage and numerous poorly staining oval to tear-drop shaped organisms. These organisms stained brightly acid fast, and some included two polar capsules and a polar filament. No other signs of infection were noted in these fish. Conclusion: This is the first histopathologic description and report of myxozoan parasites in the cascadura in Trinidad. Myxozoa can be pathogenic, and should be included in the differential for causes of death in farmed cascadura, particularly when there is poor water quality which could affect the immune system of the fish.

Histogenesis of intrapulmonary and endobronchial hamartomas and chondromas (cartilage-containing tumors): a hypothesis

A study of selected examples from a series of 42 cartilage-containing tumors of the lung support the hypothesis that intrapulmonary hamartomas and chondromas and endobranchial hamartomas and chondromas are the same lesion and are neoplasms that arise in the connective tissue of the bronchial walls. The apparent differences in the appearance of these neoplasms are due to their site of origin. i.e., whether they arise in large or small bronchi, and their direction of growth, i.e., whether they grow into or away from the lumen of the bronchus of origin. They should all be referred to as cartilage containing tumors of the lung and bronchi. (Summary)