Characterizing Two New Henneguya Species in the Respiratory Organs of African Sharptooth Catfish.

Henneguya species are myxozoans, a suborder of Cnidaria, which can affect the gills and extrarespiratory organs of the African sharptooth catfish, Clarias gariepinus. This research describes natural infection-induced histological alterations caused by the Henneguya species present. The Henneguya species were also identified molecularly using DNA sequenced from infected tissue cysts, and phylogenetically analyzed. Clinical investigations revealed cyst-like nodules on the fish gill filaments and extrarespiratory organs. Within a milky fluid inside the cysts were several Henneguya-like spores. Henneguya sp. infested 27.5% of the fish, with the highest prevalence in the gills compared to the extrarespiratory organs. The Henneguya species parasitized the gill and the dendritic tissues, resulting in histopathological characteristics. The plasmodia's developmental stages resulted in destructive damage which manifested as marked necrosis, which was replaced by a focal aggregation of inflammatory cells. Amplification of the 18S ribosomal DNA from the fish parasites was followed by sequencing, which confirmed their identities as new species Henneguya qenabranchiae n. sp. and Henneguya qenasuprabranchiae n. sp. with 99.53 and 99.64% identities, respectively, to Henneguya sp. 1 HS-2015. The two C. gariepinus myxozoans shared some characteristics based on morphologic and phylogenetic analysis as previously published, where it was proposed that they were a sister lineage to Henneguya species in Egypt, and it is now proposed that they are new species.

Occurrence of Eimeria species (Apicomplexa: Eimeriidae) in domestic rabbits (Oryctolagus cuniculus) in Qena Governorate, Upper Egypt.

The importance of rabbits for economic, medical, and biological purposes has been well appreciated. In the present study, a total of 200 domestic rabbits were collected from Qena Governorate, Egypt, from 2018 to October 2020. Their fecal samples were tested for the presence of Eimeria species oocysts using the standard flotation technique, which revealed oocysts in 100 rabbits (50%). The following 11 species of Eimeria were examined morphologically and morphometrically from different parts of the rabbits intestine (duodenum, ileum, cecum, colon, and rectum): Eimeria coecicola (8%), E. exigua (65%), E. flavescens (30%), E. irresidua (35%), E. magna (10%), E. media (25%), E. perforans (63%), E. intestinalis (50%), E. stiedae (2%), E. vejdovskyi (5%), and E. piriformis (3%). Moreover, the endogenous stages of E. intestinalis were examined by light and transmission electron microscopy. Macrogametogenesis and microgametogenesis were observed. The development of microgamonts, macrogametes, and oocysts with their fine structural characteristics was detected. Additionally, in this study E. stiedae, E. irresidua, and E. vejdovskyi are reported for the first time in Qena, Upper Egypt. The present study calls for further study on these species with a focus on providing molecular phylogenetic work and declaring control strategies against these species.

Morphometry, molecular identification and histopathology of Passalurus ambiguus Rudolphi, 1819 in domestic rabbits (Oryctolagus cuniculus) in Qena, Upper Egypt.

In Egypt, domestic rabbits are commercially used for meat production. Adversely, gastrointestinal helminthiasis largely delays such concern. Passalurus ambiguus is a common intestinal nematode that infects rabbits causing intestinal disorders and death in severe infection. Therefore, domestic rabbits collected from several locations (poultry slaughter shops, rabbits farms, markets and public owners) in Qena, Upper Egypt. Passalurus ambiguus worms were detected in 90 out of 200 rabbits (45%). Grossly, they appeared as small white nodules in the appendix of the rabbits examined. Adult worms were described morphologically using light and scanning electron microscopy. Adult male measured 4.622 mm (2.838-7.172 mm) in length and 0.278 mm (0.139-0.558 mm) in width. Adult female measured 5.622 mm (2.347-9.532 mm) in length and 0.314 mm (0.185-0.381 mm) in width. SEM showed a transverse cuticular striations on the body of both males and females, four papillae on the dorsal and ventral surface and the mouth was triangular and surrounded by three teeth. Phylogenetic data proved the occurrence of the intestinal nematode, Passalurus ambiguus. Microscopically, heavy worms infestated the appendiceal layers causing appendicitis manifested by granuloma with hyperplasia in the epithelial lining inducedobstruction in the lumen. It could be concluded that morphological features, molecular phylogenetic data, and histopathological findings clearly identified the present species as Passalurus ambiguus Rudolphi, 1819.

Henneguya species infecting the gastrointestinal tract of Clarias gariepinus from the Nile River.

As part of a study on parasitic infection in the African sharptooth catfish Clarias gariepinus, we found cysts of varying sizes in the stomach and intestine that contained myxospores with morphological features resembling those of the genus Henneguya. The present investigation was carried out with data on spore morphology and histopathology. Additionally, the myxozoan was identified using a molecular-based approach with 18S small subunit rDNA sequences. Based on the morphological characterization and tissue specificity of Myxozoa, 2 species of Henneguya were identified in the catfish stomach and intestine. Several histopathological changes were observed in the intestine which may affect fish performance and survival. The phylogenetic position of nucleotide sequences of the Henneguya species identified here were clustered with other fish-infecting Henneguya species. These sequences were deposited in GenBank. It appears that they potentially represent 2 species, denominated Henneguya sp. 1 and Henneguya sp. 2 according to the samples originating from the stomach and intestine, respectively. Although future investigations are needed for detailed morphological and molecular descriptions, this study documents the likely occurrence of infection with Henneguya noted for the first time, to our knowledge, in the digestive system of C. gariepinus in Egypt.

Detection of Neoascarophis mariae (Nematoda: Cystidicolidae) parasitic in Parupeneus forsskali and Mulloidichthys flavolineatus (Perciformes: Mullidae) from the Red Sea in Egypt.

The nematode parasite Neoascarophis mariae was collected from the intestine of Parupeneus forsskali and Mulloidichthys flavolineatus from the Red Sea in Egypt and was described using both light and scanning electron microscopy. It is mainly characterized by the presence of four submedian labia surrounded the oral aperture in the outer side, two sublabia and two pseudolabia in the inner side, rounded cephalic end, and short vestibule in both sexes. The females vulva is located near the posterior end of the body, their oval uterine eggs have a smooth surface devoid of filaments. Males have bifurcated deirids, a large left spicule (85-425 µm) with a tapered tip, and a short right spicule (50-181 µm) with a broad and rounded tip.

First molecular characterization of Sarcocystis spp. in cattle in Qena Governorate, Upper Egypt.

Cattle are intermediate hosts for several Sarcocystis species with different definitive hosts. The present study, to our knowledge, is the first to determine the prevalence of Sarcocystis infection and morphologically and molecularly identify Sarcocystis species in cattle in Qena Governorate, Upper Egypt. The samples were collected from the heart and oesophagus muscles of 84 slaughtered cattle (76 males and 8 females) aged between 11 months and 3 years from slaughterhouses in different localities in Qena Governorate, Upper Egypt. The samples were macroscopically and histologically examined, and the molecular identification of the species was performed using 18S ribosomal subunit DNA through PCR and DNA sequencing. Infection was detected in 72 out of 84 animals (85.7%) and was more prevalent in males (76.2%) than in females (9.5). Using light microscopy, the microscopic sarcocysts were observed to be thin-walled. Sequencing and genotyping revealed one isolate that had 99 and 100% identity, respectively, to Sarcocystis cruzi, while another isolate had 95 and 99% identity to Sarcocystis hjorti. The present study is the first to identify Sarcocystis infection in cattle in Qena Governorate, Upper Egypt both morphologically and molecularly. Sarcocystis cruzi and S. hjorti species were isolated from cattle, which is of veterinary importance and indicates that morphologically similar Sarcocystis species are genetically distinct. Additionally, the results show that Sarcocystis species are not host-specific.