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Background: Nutritional interventions with natural antioxidants can provide a pragmatic solution for modifying hens’ performance and maintaining oxidative stability of eggs during storage. Quercetin is the most abundant flavonoids with potent antioxidant and immune stimulant activities. The concept of incorporating of quercetin, as potent antioxidant and immunostimulant, into effective nano-carriers (QNPs) has promoted their bioavailability and stability thus, their effectiveness for the first time were assessed on laying hens’ performance and immunity, eggs quality during storage. Four hundred 12-weeks-old Hy-line brown laying hens were distributed to four experimental groups: control group fed basal diets, and other 3 groups fed basal diets fortified with 100, 200 and 300 mg/kg QNPs for 60 weeks. Results: Laying performance and quality of laid eggs were improved as expressed by elevated laying rate, egg mass %, eggs weight and yolk weight in QNPs200 and 300. Fortification of QNPs300 remarkably decreased layers serum total cholesterol concurrently with decreased egg yolk saturated fatty acids and cholesterol while increased polyunsaturated fatty acids. Over- 45 days storage period, QNPs enhanced phospholipids, total phenolics and flavonoids, total antioxidant activity (T-AOC) simultaneous with decreased MDA content in eggs. Furthermore, enhanced immune response was detected in both in serum and intestine of QNPs fed hens as reflected by higher lysozymes activity, IgM, IgG and phagocytic index and demotion of NO together with AvBD 6–12, IL-10, IgM and ATg 5-7-12 upregulation and downregulation of IL-1β and TNF-α especially at QNPs200 and 300. Intestinal redox balance was modified via decreasing H2O2 and MDA simultaneous with upregulation of catalase, SOD, GSH-Px, HO-1 and NQO1 in groups fed higher doses of QNPs. Conclusions: QNPs supplementation provides a new nutritional strategy towards increasing hen performance, fortification of eggs with natural antioxidants that prevents egg quality deterioration during storage. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Nowadays, many studies have been carried out to develop new eco-friendly alternatives consequently, the essential oils (EOs) have acquired more interest due to their insecticidal activities, low harmfulness, and rapid degradation in the environment. Following this approach, herein we tried to improve the insecticidal activities of Pelargonium graveolens (G) through using the geranium oil in nano-emulsion (GN) form and in combination with sesame seed oil (SO). Different concentrations ranged from 0.313 to 10% were prepared from GN and the combination of G with S and tested for their larvicidal and pupicidal activities against Musca domestica and Culex pipiens, while their adulticidal activities were tested against red flour beetle Tribolium castaneum. The LC50 of G alone was 4.29% against house fly larvae. The values of LC50 decreased to 1.50% for GN and 0.32% for the combination of G+S. GO and GN form induced (pupal toxicity) 100% inhibition rate (PIR) in the treated housefly pupae at the concentration of 10%. Meanwhile, GO+SO combination showed 100% PIR at the concentration of 2.5%. Furthermore, the LC50 for GO, GN and GO+SO was 0.22, 0.19 and 0.079 % respectively against larvae of C. pipiens, while it was 1.04 % for sesame oil. Regarding the contact and fumigant assays against adult T. castaneum, the combination of G and S achieved the best results when compared with GO alone or GN form. All treatments exhibited inhibition in the activity of acetylcholinesterase enzyme in the house fly larvae 24h post application. In addition, all the treatments induced significant increase in the malondialdehyde activity. In conclusion, nanoemulsion tech and mixing GO+SO increased their insecticidal potency against house fly, C. pipiens and T. castenum. This is a useful method in the integrated pest management. [ABSTRACT FROM AUTHOR]