## 3 Results and Discussion
### Method Validation
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Feed**} & \multicolumn{2}{c}{**Added Concentration**} & \multicolumn{2}{c}{**Recovery Rate**} & \multicolumn{2}{c}{**Intra Batch Coefficient of**} & \multicolumn{2}{c}{**Inter Batch Coefficient of**} \\  & \multicolumn{2}{c}{**(\(\mu\)g/g)**} & **(\%)** & **Variation (\%)** & **Variation (\%)** \\ \hline \multirow{2}{*}{\begin{tabular}{c} Chicken compound \\ feed \\ \end{tabular} } & 0.05 & 89.33 & 3.42 & 4.57 \\ \cline{2-5}  & 0.5 & 87.36 & 4.18 & 5.90 \\ \cline{2-5}  & 5.0 & 86.10 & 4.07 & 5.82 \\ \hline \multirow{2}{*}{\begin{tabular}{c} Concentrated \\ feed \\ \end{tabular} } & 0.1 & 91.52 & 8.46 & 9.26 \\ \cline{2-5}  & 1.0 & 87.77 & 3.70 & 4.51 \\ \cline{2-5}  & 10.0 & 90.45 & 7.85 & 7.95 \\ \hline \multirow{2}{*}{\begin{tabular}{c} Chicken \\ premix feed \\ \end{tabular} } & 0.5 & 89.08 & 7.17 & 8.62 \\ \cline{2-5}  & 5.0 & 93.26 & 5.63 & 6.38 \\ \cline{2-5}  & 50.0 & 95.36 & 4.85 & 6.07 \\ \hline \multirow{2}{*}{\begin{tabular}{c} Pig compound \\ feed \\ \end{tabular} } & 0.05 & 85.37 & 5.76 & 8.42 \\ \cline{2-5}  & 0.5 & 80.42 & 8.02 & 9.65 \\ \cline{2-5}  & 5.0 & 83.55 & 3.94 & 5.74 \\ \hline \multirow{2}{*}{\
\begin{tabular}{c} Concentrated \\ pig feed \\ \end{tabular} } & 0.1 & 82.73 & 10.11 & 11.66 \\ \cline{2-5}  & 1.0 & 80.96 & 7.05 & 8.09 \\ \cline{2-5}  & 10.0 & 85.77 & 7.29 & 8.75 \\ \hline \multirow{2}{*}{
\begin{tabular}{c} Pig premix \\ feed \\ \end{tabular} } & 0.5 & 96.64 & 11.33 & 10.93 \\ \cline{2-5}  & 5.0 & 95.28 & 5.82 & 7.80 \\ \cline{2-5}  & 50.0 & 90.78 & 6.78 & 9.48 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Recovery rate and coefficient of variation in avermectin B1a added to feed. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Feed**} & \multicolumn{2}{c}{**Added Concentration**} & \multicolumn{2}{c}{**Recovery Rate**} & \multicolumn{2}{c}{**Intra Batch Coefficient of**} & \multicolumn{2}{c}{**Inter Batch**} \\  & \multicolumn{2}{c}{**(\(\mu\)g/g)**} & **(\%)** & **Variation (\%)** & **Variation (\%)** \\ \hline \multirow{2}{*}{\begin{tabular}{c} Chicken compound \\ feed \\ \end{tabular} } & 0.05 & 87.13 & 4.95 & 5.17 \\ \cline{2-5}  & 0.5 & 82.75 & 4.67 & 4.85 \\ \cline{2-5}  & 5.0 & 85.48 & 2.88 & 4.66 \\ \hline \multirow{2}{*}{\begin{tabular}{c} Chicken \\ premix feed \\ \end{tabular} } & 0.1 & 81.17 & 9.97 & 8.74 \\ \cline{2-5}  & 1.0 & 83.76 & 4.85 & 11.76 \\ \cline{2-5}  & 10.0 & 88.45 & 5.72 & 9.28 \\ \hline \multirow{2}{*}{\begin{tabular}{c} Pig premix \\ feed \\ \end{tabular} } & 0.5 & 98.07 & 10.14 & 10.59 \\ \cline{2-5}  & 5.0 & 96.82 & 7.24 & 8.82 \\ \cline{2-5}  & 50.0 & 95.44 & 5.08 & 6.75 \\ \hline \multirow{2}{*}{\
\begin{tabular}{c} Vitamin \\ supplements \\ \end{tabular} } & 0.05 & 90.50 & 4.37 & 5.55 \\ \cline{2-5}  & 0.5 & 91.73 & 6.42 & 7.12 \\ \cline{2-5}  & 5.0 & 88.42 & 3.79 & 4.71 \\ \hline \multirow{2}{*}{
\begin{tabular}{c} Cattle \\ concentrate \\ \end{tabular} } & 0.1 & 85.78 & 7.90 & 10.76 \\ \cline{2-5}  & 1.0 & 83.12 & 11.26 & 12.55 \\ \cline{2-5}  & 10.0 & 81.94 & 9.97 & 10.87 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: _Cont._ \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Feed**} & \multicolumn{2}{c}{**Added Concentration (\(\mu\)g/g)**} & \multirow{2}{*}{**Recovery Rate (\%)**} & \multicolumn{2}{c}{**Intra Batch Coefficient of Variation (\%)**} & \multicolumn{1}{c}{**Inter Batch**} \\ \cline{3-5}  & & 0.05 & 87.72 & 5.46 & 6.75 \\ \cline{2-5} Vitamin & 0.5 & 86.66 & 7.39 & 8.82 \\ \cline{2-5} supplements & 5.0 & 84.53 & 4.74 & 5.46 \\ \hline \multirow{4}{*}{Cattle concentrate} & 0.1 & 83.18 & 8.29 & 9.73 \\ \cline{2-5}  & 1.0 & 80.07 & 10.78 & 11.16 \\ \cline{2-5}  & 10.0 & 80.22 & 10.32 & 11.49 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: _Cont._