Description of hyperparasitism of microsporidia in nematode (Ascaridia galli) parasitic in fowl, Gallus gallus domesticus

Abstract

Microsporidia are intracellular, obligate parasites. They have wide infection range from diverse phyla of invertebrates to vertebrates and also these eukaryotic pathogens parasitize those hosts which themselves are parasites, thus revealing hyperparasitism. The present study describe intracellular pathogen microsporidia which is isolated from a nematode parasite, Ascaridia sp. which itself is a parasite of fowl, Gallus gallus domesticus. The initial detection by optical microscopy represented numerous refractive oval spores in the homogenate samples of nematodes with mean spore length and width of 4.32±0.32μm×1.57±0.26μm (N=10). Giemsa staining exhibited demarcating stages of spore development. Spores developing in sporophorous vesicle, mature spores of considerable size and shape, dividing sporonts and sporoblasts, were clearly noticeable. However, the phases of proliferation (merogony) were indistinguishable. The ultrastructural study by Scanning electron microscopy illustrated intracellular development of microspor-idian spore inside nematode tissues. Xenoma formation as well as spore adherence to the epithelial wall most likely indicated the degradation and auto-infection by the microsporidian spores in the host tissue. A spore infecting host tissue by ejecting its polar tubule was also captured. Thus, the overall study focuses on developing microsporidia as hyperparasite in nematodes, although further classification for determining the genus has been left to be explored.