Arpášova H. et al./Scientific Papers: Animal Science and Biotechnologies, 2016, 49 (2) 10 The Effect of Propolis Extract on Internal Quality Parameters of Table Eggs Henrieta Arpášová * , Peter Haščík, Veronika Pistová, Martin Mellen, Branislav Gálik, Martin Fik Slovak University of Agriculture, 949 76 Nitra, Tr. A. Hlinku 2, Slovak Republic Abstract The aim of our experiment was to evaluate the influence of propolis extract on internal egg quality parameters of laying hens’ hybrid Hy-Line Brown. For housing hens (n=40) three storey enriched battery cage was used in which hens were divided in groups (n=10). In the control group of hens complete feed mixtures without any additions were fed. In the first experimental group complete feed mixture was enriched with propolis extract in a dose of 0.1 g.kg -1 . In the second experimental group propolis extract was added to the feed mixture at a dose of 0.25 g.kg -1 . The third experimental group was enriched with propolis extract in a dose of 0.4 g.kg -1 . All groups were fed ad libitum. Complete analysis of the table egg quality was used to evaluate quality parameters: egg weight (g), albumen weight (g), albumen index, Haugh Units (HU), yolk weight (g), yolk index, yolk colour (HLR). The results show that supplementation of feed mixture with propolis extract in a doses 0.25 g.kg -1 and 0.4 g.kg -1 significantly increased egg albumen index and Haugh Units (p0.05) (values of Haugh Units of albumen in the order of the groups (mean±S.D): 79.87±7.23, 80.58±7.60, 82.11±8.36, and 81.66±9.16 HU). However, the addition of propolis extract in a same doses significantly decreased yolk weight (p0.05). The values of the other eggs quality indicators were comparable with the control group (p>0.05). Keywords: egg quality, egg weight, laying hens, propolis extract 1. Introduction Propolis is a bee product with a characteristic smell and excellent disinfection effects. Propolis is collected by bees from flower buds, parts of trees and plants secretions. The basis of propolis is sticky resin (oil) from growing up buds of trees and flowers. Bees collect resin, processed and mixed with enzymes and wax to propolis [1]. Propolis is used in the pharmaceutical industry, in human and veterinary medicine [2]. Propolis is composed of 30% wax, 50% resin, 10% of essential oils, 5% pollen and other substances. It was shown to contain iron, calcium, copper, * Corresponding author: Arpášová Henrieta Email: henrieta.arpasova@uniag.sk magnesium, zinc, manganese, chromium, strontium, silicon. It contains flavonoids, phenolic acids and their esters, waxes, and fatty acids, essential oils, minerals and organic acids. It is a natural and well-balanced substance with significant antibiotic and immunomodulatory effects [3]. It also has the effects of anti- carcinogenic, antioxidant [4, 5], anti-inflammatory [6], antifungal [7], antihepatotoxic [8], and the antibacterial [9]. Propolis is a natural and well- balanced substance with significant antibiotic and immunomodulatory effects. Dias et al., 2012 [10] analyzed propolis and pollen collected from poplar, oak summer, mountain pine and chestnut. The results reported antimicrobial activity of propolis related to infection by Staphylococcus aureus methicillin-resistant (MRSA). The antimicrobial activity of propolis is associated with the physical structure. The composition of propolis depends on the type of wood from which