The microbial burden load of eggshells from different poultry rearing systems in Ekosodin Village, Edo State, Nigeria

Abstract

Eggs are valuable source of food used throughout the world to feed the ever growing world population. Majority of freshly laid eggs are sterile, however, the shells soon become contaminated with litter droppings and dust present in the environment. In this study, the microbial load of egg shell from different poultry system in Ekosodin, Edo State was evaluated. The results obtained from the study revealed that eggshell samples from different poultry rearing systems (battery cage, deep litter and free-range chicken eggs) were contaminated with bacterial and fungal species of public health concern. Microbial species isolated from eggshells were Enterobacter aerogenes, Escherichia coli, Citrobacter freundii, Bacillus cereus, Enteroccocus faecalis and Proteus mirabillis for the bacterial isolates while the fungi isolates include Mucor sp., Rhizopus sp., Aspergillus sp., Fusarium sp. and Penicillium sp. The bacterial and fungal load of free-range chicken eggshell ranged from 9. 7 ± 0.7 x 10⁴ to 1. 27 ± 0.2 x 10⁵ and 7. 0 ± 0.5 x 10³ to 2. 2 ± 0.5 x 10⁴ cfu/g respectively. Bacterial and fungal counts were 3. 3 ± 0.8 x 10⁴  to 7. 4 ± 0.5 x 10⁴ and 1. 1 ± 0.1 x 10⁴ to 1. 6 ± 0.4 x 10⁴ cfu/g for battery cage eggshells and 6. 8 ± 0.9 x 10⁴ to 1. 38 ± 0.5 x 10⁵ and 2.0 ± 0.3 x 10⁴ to 3. 7 ± 0.5 x 10⁴ cfu/g for deep litter eggshells respectively. Statistically, the mean fungi count of deep litter egg shells samples differed significantly (P<0.05) from the mean fungal count of battery cage and free-range chicken eggshells. Also, the mean bacterial count of battery cage egg shells differed significantly from deep litter and free-range chicken eggshells (P<0.05). The presence of these microorganisms on eggshell might constitute a serious risk to consumers. Proper education to enlighten retailers and consumers by the government on microbial quality of table eggs is important. Proper sanitation and battery cage system of rearing eggs should be encouraged.

Keywords: Deep litter system, battery cage system, eggshell microbial load, microbial quality of table eggs