Microscopic fungi in eggs of ring-necked pheasants kept in aviaries.

Pheasant eggs of different colors differ with regard to physical properties. This study was conducted to ascertain the intensity of infestation by microscopic fungi based on egg color. Settling intensity by microscopic fungi of pheasant egg shells and the content of eggs of different color during a 7-d storage period was investigated. The content of ergosterol (ERG) was used as a quantitative indicator of microscopic fungi and yeasts in the egg. The highest ERG content was determined in blue- and light brown-shelled eggs, both nonstored (0 d) and stored (7 d). A similar tendency was observed when assessing ERG content in the egg white. The difference between blue- and light brown-shelled eggs and the remaining eggs amounted to approximately 0.95 mg/kg. Differences in the ERG content in the whites of eggs stored for 0 and 7 d were determined to be 0.80, 1.63, 1.91, and 0.85 mg/kg for blue-, olive-, light brown-, and dark brown-shelled eggs, respectively. The performed quality analysis of the mycoflora found on pheasant eggs indicated a considerable proportion of molds from the Aspergillus genus as well as the occurrence of single colonies from Penicillium and Rhizopus genera. The only yeasts determined on the egg surface of the examined eggs belonged to the Rhodotorula genus. The performed investigations demonstrated that microscopic fungi pose a potential hazard to pheasant embryos.

Ergosterol as an indicator of the presence of microscopic fungi in eggs for human consumption produced in different husbandry systems.

Ergosterol (ERG) content, being an indicator of fungal biomass, was analyzed in samples of eggshell, egg white, and egg yolk from eggs from farms with intensive management systems of layer hens (i.e., cage and litter housing). Moreover, analogous samples were analyzed from eggs from farms in the western central part of Poland, where layer hens were kept in the organic system. In all samples, the highest ERG concentration was found in shells and the lowest in egg white, whereas ERG was not found in egg yolk. When comparing investigated housing systems, a higher concentration of the analyzed metabolite was detected in eggs from litter housing than in eggs from cage housing. Concentrations of ERG in samples of eggs from organic husbandry were highly varied, ranging from 2.44 to 42.67 mg/kg in shells and from 0.28 to 16.11 mg/kg in egg white.