Summary: Cystic echinococcosis is an important cosmopolitan parasitic zoonosis that causes public health and economic problems in Egypt. The present study was undertaken to identify genotypes of hydatid cyst (HC) DNA isolated from different animal isolates and to identify the genotype of secondary hydatid cysts (HCs) developed in rabbits experimentally infected with camel HC for detection of any genetic mutation. In the present study, we extracted DNA from the germinal layers of 8 HCs collected from 3 camels, 1 cattle, 1 sheep and 3 donkeys in addition to 3 secondary HCs collected from rabbits experimentally infected with camel HC. PCR amplification of the ITS1 gene of all examined samples showed an amplified DNA band at 1115 bp. The partial nucleotide sequences of the ITS1 gene of all isolates were aligned and compared with the reference sequences of the genotypes G1–G8 in GenBank. The camel and rabbit samples were identified as Echinococcus canadensis genotype 6 (G6), while the cattle and sheep samples belonged to E. granulosus sensu stricto (G1). The donkey isolates belonged to E. equines (G4). Alignment of the ITS1 partial nucleotide sequences of the camel HCs and rabbit secondary HCs isolates with the G6 partial nucleotide sequence in GenBank was performed. Both camel HCs and rabbit secondary HCs isolates exhibited the same sequence identity matrix, which indicated the absence of mutation in the rabbit secondary HCs. It can be concluded that camel and rabbit samples were identified as E. canadensis (G6), the cattle and sheep samples belonged to E. granulosus sensu stricto (G1) and donkey isolates belonged to E. equines (G4). No mutation occurred during HCs transmission from camel to rabbit.

Trichomonas gallinae is a protozoan parasite that causes canker in pigeons. Squabs (young pigeons) are frequently infected with T. gallinae and can die because of the infection, while adult pigeons can act as carriers showing no clinical signs. In the present study, 50 squabs, up to 1-month-old, were purchased from pigeon markets in different regions of the Giza governorate, Egypt. Direct wet mount preparations of the oral excretions of the squabs (mouth wash) and Giemsa staining revealed that 64% (32/50) were positive for T. gallinae. Experimental infection of ten squabs with 10³ T. gallinae trophozoites/ml resulted in oral lesions on the mouth, tongue, and soft palate, with the presence of yellowish-white nodules (cheese-like) in the oral cavity on the sixth day post-infection in all squabs. A subset of five samples were cultured in modified Diamond’s media, their DNA was extracted, and a portion of the ribosomal internal transcribed spacer region (ITS1/5.8S/ITS2) was amplified by polymerase chain reaction (PCR) followed by sequencing. Phylogenetic analysis of the five isolates revealed 64–91% homology with some reference isolates circulating in Egypt and related countries.

Neospora caninum infection is a major cause of abortion in dairy and beef cattle in many countries. Fast and accurate diagnosis of neosporosis is still the best disease control strategy. Thus, Np6 and Np21 primer sets were employed for the detection of N. caninum in the blood of 139 aborted cows and tissues of 25 foeti during a wave of abortion in five dairy farms in Egypt. The results revealed a 47.5% overall prevalence of N. caninum infection in aborted cows and a 64% overall prevalence in foeti. Two farms were PCR negative for the infection, and the other farms presented 45.7%, 87.0% and 90.9% molecular prevalence. The majority of PCR-positive foeti were aborted in the fifth month of pregnancy. The most common PCR-positive fetal tissue was the brain, followed by the heart, liver, stomach contents, and then the lung. The histopathological lesions in 5-month-old aborted foeti were microgliosis in the brain meninges and submeningially and myocarditis in heart tissue. At 7 months of abortion, multifocal necrosis, mononuclear cell infiltration, and neuron degeneration were observed in the brain. Heart tissue showed hemorrhage and necrotic changes. A tissue cyst was observed in the heart of 5-month aborted foeti and the brain of 7-month-old foeti. The sequenced amplicons from aborted cows and foeti were 100% identical to each other. As far as we are aware, our investigation is the first to sequence isolates of N. caninum from cattle hosts. The sequences were submitted to GenBank with the accession numbers OR939832.1 and PP708713.1. Multiple sequence alignments revealed variation between the study isolates and other published isolates from different regions and hosts. Phylogeny revealed clustering of our sequences with sequences of isolates from South Korea, China, and Italy. The sequences were distinct from sequences previously isolated from camels in Egypt.