# Occurrence of Fungi on Duck Egg Shells and Drug Resistance Analysis of _Aspergillus_ spp. Isolates
## 4 Discussion  
The results obtained from this study showed that eggshell samples from different reproductive duck flocks presented various levels of fungal contamination. The contamination scale did not depend on the different breeding systems, which was observed in hen flocks [8; 16; 17], because ducks' parental flocks are kept in deep litter, and the eggs are laid in nests filled with straw. We suspect that various levels of eggshell contamination depended on the hygiene and the straw disinfection and its preservation on each farm. The commonly cultured fungal genera in this study were _Aspergillus_, _Alternaria_ and _Penicillium_. Polish research on table egg contamination showed the presence of fungi belonging to the _Alternaria_, _Penicillium_, _Chaetomium_ and _Aspergillus_ genera [9], which is consistent with our research. Not many data on the fungal contamination of duck eggs are available, but researchers from Egypt conducted a similar investigation, where _Penicillium_ \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{5}{c}{**MIC (\(\mathrm{\mu g}\)/mL)**} \\ \hline \multicolumn{1}{c}{\begin{tabular}{c} **Antimicrobial Agents** \\ \end{tabular} } & \multicolumn{1}{c}{\begin{tabular}{c} **MIC\({}_{\mathrm{50}}\)** \\ \end{tabular} } & \multicolumn{1}{c}{\begin{tabular}{c} **MIC\({}_{\mathrm{90}}\)** \\ \end{tabular} } & \multicolumn{1}{c}{\
\begin{tabular}{c} **Range** \\ \end{tabular} } & \multicolumn{1}{c}{
\begin{tabular}{c} **\% Resistance** \\ \end{tabular} } \\ \hline \multicolumn{1}{c}{AMB} & 1 & 32 & 0.94–32 & 47.4 \\ \hline \multicolumn{1}{c}{CAS} & 0.38 & 32 & 0.125–32 & 21.1 \\ \hline \multicolumn{1}{c}{ITC} & 1.5 & 32 & 0,19–32 & 68.4 \\ \hline \multicolumn{1}{c}{POS} & 0.5 & 8 & 0.047–12 & 73.7 \\ \hline \multicolumn{1}{c}{VOR} & 0.19 & 32 & 0.023–32 & 31.6 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: In vitro activity of 5 antifungal agents against _Aspergillus fumigatus_ isolates (\(n=19\)). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{1}{c}{\begin{tabular}{c} **Isolate Number** \\ **(\(n=19\))** \\ \end{tabular} } & \multicolumn{1}{c}{\begin{tabular}{c} **AMB** \\ \end{tabular} } & \multicolumn{1}{c}{\begin{tabular}{c} **CAS** \\ \end{tabular} } & \multicolumn{1}{c}{\begin{tabular}{c} **ITC** \\ \end{tabular} } & \multicolumn{1}{c}{\
\begin{tabular}{c} **POS** \\ \end{tabular} } & \multicolumn{1}{c}{
\begin{tabular}{c} **VOR** \\ \end{tabular} } \\ \hline \multicolumn{1}{c}{D1} & 0.75 & 0.38 & **3.0** & **0.38** & 0.125 \\ \multicolumn{1}{c}{D2} & 0.094 & \textgreater{}**32** & **>32** & **12** & **>32** \\ \multicolumn{1}{c}{D3} & 0.50 & \textgreater{}**32** & **1.5** & **0.5** & 0.19 \\ \multicolumn{1}{c}{D4} & 0.75 & 0.25 & 0.19 & 0.19 & 0.023 \\ \multicolumn{1}{c}{D5} & 1.0 & 0.38 & \textgreater{}**32** & **8** & **>32** \\ \multicolumn{1}{c}{D6} & \textgreater{}**32** & 0.25 & 0.38 & 0.19 & 0.047 \\ \hline \multicolumn{1}{c}{K1} & \textgreater{}**32** & **>32** & **1.5** & **2.0** & **>32** \\ \multicolumn{1}{c}{K2} & 0.75 & 0.38 & 0.19 & **0.5** & 0.19 \\ \multicolumn{1}{c}{K3} & \textgreater{}**32** & 0.25 & 0.38 & 0.19 & 0.047 \\ \multicolumn{1}{c}{K4} & 0.75 & \textgreater{}**32** & 0.19 & 0.19 & 0.5 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: _Cont._and _Aspergillus_ were the most prevalent on the eggshells, followed by _Cladosporium_, _Accmonium_, _Mucor_ and _Fusarium_[18; 19]. Our research shows that _Aspergillus_ contamination is not of a high level, and the dominating fungi were of other genera. The litter could be the main source of fungal spores, which was confirmed by researchers studying different types of litter which were contaminated with fungal genera such as _Aspergillus_, _Cladosporium_, _Penicillium_, _Stemphylium_, _Mucor_, _Rhizopus_, _Fusarium_, etc. [20; 21; 22; 23]. The investigations relating the type of litter with fungal contamination showed that the most contaminated type proved to be chopped straw, and flocks littered with sawdust and wood chips were the least contaminated by microscopic fungi [20].