الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 128 |  |  |
| | | from | 128 | | |
Abstract
Three hundred and seventy five (375) random samples of eggs, represent 75 groups (five eggs each), were collected from Assiut city markets and poultry farms in summer and winter. The samples were dispatched to laboratory in sterile plastic bags for microbiological examination.
I- Microbiological examination :
A- Enumeration of different microorganisms :
The obtained results revealed that, the average values of total colony, yeast and mould and Enterococci counts recovered from shells of fresh egg samples collected in summer months were 4.4x105, 2.5x103 and 1.3x104/shell,resp-ectively. S. aureus organisms could not be detected in all of samples examined. In winter, the averages of total colony and Enterococci counts/shell were 3.9x105 and 6.1x103, respectively, while, yeast & mould and S. aureus organisms failed to recover from the examined samples.
The average counts of total colony, yeast & mould, Enterococci and S. aureus recovered from marketable egg shells collected in summer and winter were 3.3x109 & 3.2x107, 7.4x104 & 3.2x104, 1.9x105 & 2.1x104 and 1.3x102/ shell,respectively. No S. aureus organisms could be isolated from the examined egg samples collected in winter.
The averages of total colony and yeast & mould counts/ ml of fresh egg contents examined in summer were 32 and 2, respectively. Enterococci count was 20/ml. In case of samples collected in winter, the average of total colony count was L. 30/m1, while, Enterococci count was 10/ml.
Yeasts and moulds were not detected. S. aureus were not found in all fresh samples collected in both summer and winter.
The averages of total colony, yeast & mould and Enterococci counts recovered from contents of marketable egg samples collected in summer and winter/ml were,respect-ively,3.1x105 & 1.3x104 for total colony count, 9.8x10 &
1.1x102 for yeast & mould and 3.4x102 & 2.3x10 for Enterococci. S. aureus count was L. 10/m1 in egg samples collected in summer and could not be detected in egg samples collected in winter.
Coliforms and E. coli were detected in 7 (70%) and 2 (20%) of the examined fresh egg shell samples collected in summer,respectively, while in winter 5 (50%) and 1 (10%), respectively.In case of marketable egg shell samples collected in summer and winter, the Coliforms and E. coli were recovered from 24 (80%) & 5 (16.7%) and 11 (44%) & 3 (12%),respectively.
One (10%) sample of fresh eggs collected in summer contained Coliform in its content, while E. call could not be detected. In case of marketable eggs collected in summer, Coliforms and E. coli were found in 8 (26.7%) and 4 (13.3%) of the examined samples, respectively. In winter, all of the examined fresh and marketable eggs were negative for Coliforms and E. coli. B- Incidence and frequency distribution of different isolates :
The incidence of S. aureus, Staph. epidermidis, Micrococci, E. coli, Serratia spp., Klebsiella spp., Enterobacter spp., Proteus rettgeri, Proteus morganii, Providencia spp., and Arizona spp. recovered from fresh egg shell samples collected
in summer was respectively, while in winter, the incidence of these microorganisms . While in marketable egg samples collected in summer and winter, the incidence of S. aureus, Staph. epidermidis, Micrococci, E. coli, Serratia spp., Klebsiella spp., Enterobacter spp., Proteus rettgeri, Providencia spp., Arizona spp. and Shigella app.
Staph. epidermidis, Micrococci, Serratia spp., and Proteus morganii were recovered from contents of fresh egg samples collected in summer with an incidence of 10 , 20 , 20 and 10%,respectively. In winter, Staph. epidermidis was detected in 10% of the examined samples. S. aureus, Staph.
epidermidis, Micrococci, E. coli, Serratia spp., Enterobacter spp., Proteus rettgeri, Proteus vulgaris, Sal. tvphimurium, Sal. newport, Sal. ohio, Providencia spp., Arizona spp., Shigella app., and Edwardsielia spp. could be isolated from contents of marketable egg samples collected in summer with an incidence of reopectively. While, the incidence of S. aureus, Staph. epidermidis, Micrococci, Serratia spp., Enterobacter spp., Providencia spp. and Arizona spp. in the examined marketable egg samples collected in winter respectively.
II- Detection of inhibitory substances :
Inhibitory substances were detected in 10 and 2.9% of the examined samples collected in summer and winter, respectively.