## 4 Discussion
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Bacteria Species**} & \multicolumn{3}{c}{**Predictors**} \\ \cline{2-4}  & **Weight Contribution by** & **Weight Contribution by PH** & **Weight Contribution by Average** \\  & **Number of Days** & **Weight Contribution by PH** & **Daily Temperature** \\ \hline _Escherichia coli_ & 0.174 & 0.077 & \(-\)0.040 \\ _Salmonella_ sp. & 0.152 & 0.056 & \(-\)0.034 \\ _Campylobacter_ sp. & 0.109 & 0.101 & \(-\)0.028 \\ _Y. enterocolitita_ & 0.193 & 0.123 & 0.024 \\ _L. monocytogenes_ & 0.311 & 0.061 & 0.003 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Weight contribution of the predictors. in manure into water bodies relies on the actual number of the pathogens shed and the release rate of the pathogens from manure [41]. The release of the pathogens from manure is a crucial factor, as it determines the availability of the pathogen for transport into environmental matrices and relates to the manure composition [42]. Therefore, owing to the 90% reduction in the enteric bacteria, the potential of the co-digestate to reach humans via water contamination and subsequently cause infections has been lessened to a greater degree as it depends on the infective dose of each bacterium; the lowest infective dose differs from one pathogen to the next. More challenging is the viability and the survival of many of the enteric pathogens outside the host organisms [43]. Accordingly, [PERSON] et al. [27] emphasised that the management of pathogen load via either anaerobic digestion or composting is a potential route to reduce and prevent outbreaks of infection with _E. coli_, _Salmonella_, _Campylobacter_, and _Listeria_; however, such studies should be considered as region-specific because of the variable parameters affecting the pathogen content and the survival in manure. In addition, it is emphasized that a reduction of one logarithmic unit or the time during which viable counts of a population of microorganisms are reduced by 90% is termed the decimation reduction time (T\({}_{90}\)). [PERSON] [44] reiterated further that the time at T\({}_{90}\) can be measured in hours and days, which is consistent with thermophilic and mesophilic digestion, respectively, and designates the variations in inactivation of bacterial pathogens in anaerobic digestion. The T\({}_{90}\) values for _E. coli_, _Salmonella_ sp., _Y. enterocolitica_, _Campylobacter_ sp., and _L. monocytogenes_ were 77 days, 84 days, 98 days, 112 days, and 175 days, respectively. The time (days) related to the percentage of decay of the bacterium and the disparity in the number of days could be attributed to the differences in bacterial biology, nutrient availability, and characteristics of the biological process [18; 23]. The data showed that _L. monocytogenes_, a Gram-positive bacteria belonging to the phylum _Firmicutes_, displayed the longest survival period as opposed to the other four Gram-negative bacterial pathogens, which belong to the phylum _Proteobacteria_. This substantiates the findings of [PERSON] et al. [18], which indicated that the inactivation of Gram-negative bacteria occurred rapidly during psychrophilic anaerobic degradation of pig manure as opposed to Gram-positive bacteria. Clearly, the peptidoglycan cell wall of bacteria offers protection and resistance to stress and hostile environmental conditions; however, the bacteria belonging to the Gram-positive category are walled by several layers of peptidoglycan and are, therefore, much thicker than those available in Gram-negative bacteria and also consist of teichoic acids [23]. The manifestation of such tendency by _L. monocytogenes_ was also highlighted by [PERSON] and [PERSON] [45] who remarked on the potential of the bacterium to thrive in vast environmental conditions (pH, water, and temperature) resulting in a greater survival ability.