Assessment Of Microbial Diversity and Abundance in Selected Sections of The Abattoir in Ozoro, Delta State, Nigeria.

This study assessed the microbial diversity and abundance in selected sections of an abattoir in Ozoro, Delta State, Nigeria, with emphasis on the impact of abattoir waste on soil microbial communities. Soil samples were collected from blood-polluted, bone-polluted, and control (unpolluted) sites at depths of 0–15 cm and 15–30 cm. Standard microbiological techniques were employed for the isolation, enumeration, and identification of bacterial and fungal populations, while biochemical tests including IMViC and urease assays were used for bacterial characterization. The results showed that the control soil recorded the highest mean bacterial count (7.50 × 10⁷ ± 1.04 × 10⁷ CFU/g), compared to blood-polluted (4.73 × 10⁷ ± 6.36 × 10⁶ CFU/g) and bone-polluted (4.90 × 10⁷ ± 1.73 × 10⁶ CFU/g) soils; however, these differences were not statistically significant (p = 0.063). Identified bacterial genera included Bacillus spp., Pseudomonas spp., Staphylococcus spp., Escherichia coli, Lactobacillus spp., and Micrococcus spp., while fungal isolates comprised Aspergillus spp., Penicillium spp., Rhizopus spp., Cladosporium spp., and Fusarium spp. Gram-positive bacteria constituted 60% of the total isolates, while Gram-negative bacteria accounted for 40%. Notably, only Gram-positive bacteria were recovered from the control soil, whereas both Gram-positive and Gram-negative bacteria were present in the polluted sites. Micrococcus spp. was highly abundant (+++), particularly in blood-polluted soil at the 0–15 cm depth, indicating its dominance in that environment. The detection of fecal indicator organisms such as E. coli and Staphylococcus spp. provided clear evidence of contamination associated with abattoir activities. Despite this, the presence of resilient indigenous microorganisms, including Bacillus, Pseudomonas, and decomposer fungi, suggests adaptive microbial responses to organic waste pollution. Overall, the findings demonstrate that improper disposal of abattoir waste alters soil microbial composition, introduces potential pathogenic organisms, and poses significant environmental and public health risks.