Characterisation of the Mycobiota on the Shell Surface of Table Eggs Acquired from Different Egg-Laying Hen Breeding Systems

Abstract

Microbial safety is an important factor contributing to the egg quality. During egg acquisition, there is significant risk of contamination of the eggshell surface with microscopic fungi. Mycelial hyphae may grow on the eggshell surface and penetrate into the egg content. However, there is no information on the populations of microscopic fungi on the eggshell surface and, consequently, on possible production of mycotoxins. Therefore, the aim of the study was to identify the species of microscopic fungi present on the eggshell surface acquired from different breeding systems and to measure the number of selected mycotoxins. The qualitative analysis resulted in the identification of 41 isolates on the surface of eggs. There were 7 isolates from the organic production system, 11 from the free-range production system, 14 from the deep litter indoor housing system and 9 from the cage farming production system. The research proved that the diversification in the population of mycobiota on the eggshells depended on the egg-laying hen breeding system. The microscopic fungi isolated from the eggshells included toxigenic and pathogenic species such as Fusarium culmorum and F. equiseti. As the egg storage time increased, fungi, including the pathogenic species, penetrated through the eggshells. In consequence, mycotoxins were identified in the egg whites. Type-A and type-B trichothecenes were found in the eggshell samples containing F. culmorum.

Cyclodepsipeptide Biosynthesis in Hypocreales Fungi and Sequence Divergence of The Non-Ribosomal Peptide Synthase Genes

“…The analyses of the ITS and tef -1α genes have been frequently employed in the phylogenetic studies of fungi belonging to the Hypocreales order [ 3 , 49 , 50 , 51 , 52 , 53 ]. However, based only on these conserved taxonomic markers, the determination of differences between closely related genotypes is often limited.…”

“…In order to analyze the sequences, amplicons were purified with exonuclease I (Thermo Scientific, Espoo, Finland) and FastAP shrimp alkaline phosphatase (Thermo Scientific, Espoo, Finland), afterwards they were labeled using forward primer and the BigDyeTerminator 3.1 kit (Applied Biosystems, Foster City, CA, USA). Finally, PCR-amplified DNA fragments were precipitated with 96% ethanol according to Tomczyk et al [ 49 ].…”

Use of reactive oxygen species (ozone, hydrogen peroxide) for disinfection of hatching eggs

“…This is due to the limited capacity of the nondisinfected shell to receive an additional number of bacterial cells. The elimination of the native microflora creates conditions for shell surface colonization by species manifesting a higher tolerance for adverse environmental conditions ( Tomczyk et al., 2018 ). The survivability of microorganisms is strictly correlated with their ability to survive and adapt to environmental changes.…”

Identification of Penicillium verrucosum, Penicillium commune, and Penicillium crustosum Isolated from Chicken Eggs

“…In the study of Neamatallah et al [35], 38% of the eggs examined were contaminated with spores of potentially toxinogenic Penicillium, Aspergillus, and Fusarium species. According to Tomczyk et al [36], fungi belonging to Alternaria, Penicillium, and Chaetomium spp. are the most common contaminants of the eggshell surface.…”