The Effect of intra egg injection of different levels of Thyme essential oil nanoemulsion on reproductive and blood parameters in Japanese quail

BACKGROUND: In recent years, injection of stimulant solutions into fertilized eggs has been considered to improve reproductive and functional parameters in birds. So far, much research has been conducted to improve embryonic development in birds by manipulating egg nutrients. In one study, injection of dietary supplements into the eggs of birds improved hatching rate, reduced mortality rate, shortened breeding time duration, increased growth rate, and increased weight gain at the end of the rearing period (Johnston et al., 1997). Egg injection technology is not only a way to vaccinate birds against certain diseases, but it is also a practical way of injecting some of the nutrients needed by the developing embryo (Foye et al., 2005 and Uni et al., 2005). Shirazi thyme (Zataria multiflora) is one of the most well-known medicinal plants. Essential oils (EOs) of shirazi thyme, that is a yellow or dark reddish brown liquid with a strong smell and a spicy and long-lasting, cooling flavour, extracted from the distillation of leaves and flowering shoots of this herb (Momeni and Shahrokhi, 1992). Essential oils comprise a complex mixture of volatile and non-volatile compounds produced by aromatic plants as secondary metabolites (Bakkali et al 2008). The main constituents of thyme EOs are flavonoide, glycosids, tannins, saponins, steroids (such as cytosterol), triterpenoids (such as oleanolic acid and ursolic acid), and volatile oils rich in monoterpenes (Martínez-Vázquez et al., 1996).Using nanoemulsions can be a great choice for the use of essential oils in foods (Jo et al., 2005). Changing the particle size to nanoparticles (size less than 100 nm) increases the surface-to-volume ratio and increases the reactivity, making it possible to use smaller amounts of these materials than materials with larger particles (Hernández-Sierra et al., 2008). The very small size of the synthesized nanoparticles can be effective in enhancing its antimicrobial effect (Krishna et al., 2011). OBJECTIVES: This study was conducted to investigate the effect of in-ova injection of different levels of nanoemulsion of thyme essential on reproductive (fertility, total hatchability, hatch of fertile eggs and embryonic mortality rates) and blood parameters (estrogen, testosterone, glucose, triglyceride, cholesterol, LDL, HDL, total protein) in Japanese quail. METHODS: The experiment was done by using 600 Japanese quail eggs in a completely randomized design with 5 treatments, 4 replications a