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Ticks pose a significant threat due to their ability to lay thousands of eggs, which can persist in the environment for extended periods. While the impact of various compounds on adult and larval ticks has been studied, research on their efficacy against tick eggs is limited. This study evaluated the ovicidal activity of commercial acaricides, disinfectants, and natural products against Rhipicephalus annulatus eggs using the egg hatch assay (EHA). Deltamethrin and cypermethrin caused a non-significant inhibition of hatching (IH%), even at concentrations higher than the recommended levels. By contrast, the acaricides chlorpyrifos, phoxim, and amitraz significantly inhibited hatching at all tested concentrations. Ivermectin also demonstrated significant IH% at various concentrations but did not fully inhibit the hatching process. Among the disinfectants tested, Virkon-S ® , TH4, and Chlorox showed insignificant effects, whereas formalin achieved an IH% of only 34.1% at a high concentration of 200 mg/mL. Natural products, carvacrol and thymol, exhibited significant ovicidal activity, with a significant IH%. In a semi-field application, phoxim (0.5 mg/mL) and deltamethrin (0.05 mg/mL) were sprayed on tick eggs on pasture soil from a farm. The results indicated that phoxim-treated eggs had a 40% IH%, while deltamethrin-treated eggs showed only an 8.79% IH%. In conclusion, the acaricides amitraz, phoxim, and chlorpyrifos, as well as the natural products carvacrol and thymol, caused significant toxicity to R. annulatus eggs.

Carvacrol is a monoterpenoid phenol found in many essential oils that has antibacterial, antifungal and antiparasitic activities. Drug loaded-invasome systems are used to deliver drugs utilizing nanoparticles to improve bioavailability, efficacy, and drug release duration. As a result, the present study developed carvacrol-loaded invasomes and evaluated their acaricidal effect against Rhipicephalus annulatus (cattle tick) and Rhipicephalus sanguineus (dog tick). Carvacrol loaded-invasome (CLI) was prepared and characterized using UV/Vis spectrophotometer, zeta potential measurements, Scanning Transmission Electron Microscopy (STEM), Fourier Transform Infrared (FT-IR) Spectroscopy, and Differential Scanning Calorimetry Analysis. CLI (5%) induced significant mortality (100%) in R. annulatus adult ticks with LC 50 of 2.60%, whereas the LC 50 of pure carvacrol was 4.30%. Carvacrol and CLI were shown to have a significant larvicidal action on both tick species, with LC 50 s of 0.24 and 0.21% against R. annulatus and 0.27 and 0.23% against R. sanguineus , respectively. Carvacrol and CLI (5%) induced significant repellent activities for 24 h against R. annulatus and R. sanguineus , as evidenced by the rod method and the petri-dish selective area choice method, respectively. High-performance liquid chromatography (HPLC) demonstrated that the CLI form had 3.86 times the permeability of pure carvacrol. Moreover, carvacrol and CLI inhibited acetylcholinesterase activity and decreased glutathione and malonedealdehyde levels in the treated ticks. In conclusion, invasomes significantly improved adulticidal and repellency activities of carvacrol against both tick species.

In Egypt, only five species of Dermaptera (earwigs) have been reported. Based on both the morphological and molecular data of the earwig samples collected from a bakery in Beni-Suef, Egypt, we identified the species as Marava arachidis (Spongiphoridae), a cosmopolitan species with no prior records in Egypt. The current study was designed to analyze its predation capability on newly emerged eggs and larvae of the Rhipicephalus annulatus tick. A laboratory functional response study was set up by applying a predation test with various predator-prey ratios as treatments. This experiment was applied using the undefined mix of collected earwigs and the laboratory-collected eggs and the larvae of R. annulatus . The laboratory results showed that the mean number of predated tick eggs was 18.64 ± 11.18 in 24 h under the highest predator-prey ratio (1:10) examined, accompanied by 12.04 ± 4.38 broken but unconsumed eggs. Moreover, M. arachidis predated an average of 12.32 ± 9.07 tick larvae per day. In contrast, the mean dead larvae increased to 38.4 ± 2.30 per day with the highest predator density (1:10). The number of eggs and larvae consumed increased with the predator density. A linear relationship was detected between earwig density and the consumption rates of tick eggs (R 2 = 0.99; p = 0.0001) and larvae (R 2 = 0.96; p = 0.003). In conclusion, M. arachidis was first recorded in Egypt. This earwig has predation capability on R. annulatus tick eggs and larvae.

The purpose of this study was to determine the course of infection in pigeons with Eimeria labbeana . Thirty-five squabs (4-6 weeks old) were brought from the local poultry market and examined for coccidial infection for 7 days to ensure they were coccidia free. A negative control group of five squabs was used, and thirty squabs were infected orally with 2.5 × 10 4 sporulated E. labbeana oocysts. From day 1-8 post-infection (PI), three squabs were scarified daily to track the endogenous stages in the intestinal tissue. Furthermore, six squabs were preserved to track the patent period and calculate daily oocyst shedding. The parasite stages were differentiated using paraffin-embedded intestinal tissues that were sectioned and stained. On day 5 PI, the infected squabs had greenish watery diarrhea, weakness, rough feathers, and decreased food intake. The pre-patent and patent durations were six and fourteen days PI, respectively. The shedding of oocysts began on day 6 PI and peaked on day 8 PI. In the duodenum and jejunum of the small intestine, histopathological investigation indicated the presence of three schizont stages, macro- and micro-gametes, and oocysts. To the best of our knowledge, this is the first study in Egypt to explore the course of E. labbeana infection in domestic pigeons., Competing Interests: Conflict of interestThe authors declare that there is no conflict of interests regarding the publication of this article., (© Indian Society for Parasitology 2021.)

Diclazuril, which is widely used for the prevention of coccidiosis in chickens, has a lethal effect on asexual and sexual stages of Eimeria spp. However, little is known about its effect on the exogenous stages of Eimeria spp. In this study, we evaluated the effect of in vitro treatment with 0.2% diclazuril on unsporulated and sporulated oocysts of Eimeria spp. For this purpose, a total of 180 male layer chicks aged one day were randomly divided into 5 experimental groups. Each group was divided into 3 replicates of 12 chicks each. Group 1 (G1) and Group 2 (G2) were negative (non-immunized and non-challenged) and positive (non-immunized and challenged) controls, respectively. Group 3 (G3) was immunized per os with 1.0 × 10 4 non-diclazuril treated-sporulated oocysts. Groups 4 (G4) was immunized per os with 0.2% diclazuril treated-unsporulated oocysts (1.0 × 10 4 ) in which diclazzuril didn't affect sporulation. Group 5 (G5) was immunized per os with 0.2% diclazuril treated-sporulated oocysts (1.0 × 10 4 ). Chicks of G2, G3, G4, and G5 were challenged with 7.5 × 10 4 untreated sporulated oocysts at the age of 21 days, while the group 1 chicks remained unchallenged. G4 and G5 animals immunized with 0.2% diclazuril-treated oocysts showed a significant decrease in bloody diarrhea severity, lesion scores, and oocyst counts in comparison to those immunized with untreated oocysts. Furthermore, histopathologic findings showed a low number of parasitic stages in cecal tissues in G4 and G5. A significant increased body weight gain was observed in Gs 4 and 5 in comparison to G2. In addition, expression levels of IL-2, IL-12, and IFN-γ were significantly increased in G4 and G5. In conclusion, diclazuril is effective in attenuating Eimeria oocysts and thus provides an alternative approach for using diclazuril-treated oocysts to protect chicks against Eimeria challenge., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Coccidiosis is a serious protozoal disease of poultry. The identification of Eimeria species has important implications for diagnosis and control as well as for epidemiology. The molecular characterization of Eimeria species infecting Egyptian baladi chickens was investigated., Methods: Eimeria species oocysts were harvested from intestines of naturally infected Egyptian baldi chickens. The morphometry characterization of oocysts along with COCCIMORPH software was done. The DNA was extracted initially by freezing and thawing then the prepared samples was subjected to commercial DNA kits. The DNA products were analyzed through conventional polymerase chain reaction by using amplified region (SCAR) marker., Results: The PCR results confirmed the presence of 7 Eimeria species in the examined fecal samples of Egyptian baldi breed with their specific ampilicon sizes being E. acervulina (811bp), E. brunette (626bp), E. tenella (539bp), E. maxima (272bp), E. necatrix (200bp), E. mitis (327bp) and E. praecopx (354bp). A sequencing of the two most predominant species of Eimeria was done, on E. tenella and E. máxima. Analysis of the obtained sequences revealed high identities 99% between Egyptian isolates and the reference one. Similarly, E. maxima isolated from Egyptian baldi chickens showed 98% nucleotide identities with the reference strain. Only single nucleotide substitution was observed among the Egyptian E. tenella isolates (A181G) when compared to the reference one. The Egyptian isolates acquired 4 unique mutations (A68T, C164T, G190A and C227G) in compared with the reference sequence., Conclusion: This is the first time to identify the 7 species of Eimeria from Egyptian baladi chickens.