Prevalence of bacterial pathogens and serotyping of E. coli isolates from diarrhoeic lambs in Sokoto state, Nigeria

A total of 127 fecal samples from diarrhoeac lambs was collected and bacteriologically cultured to determine the prevalence of pathogenic bacteria causing diarrhoea in those lambs. The samples were pre-enriched in peptone water overnight before inoculation on MacConkey agar at 37°C for 24h. The results revealed the presence of Escherichia coli 42 (36.84%), Salmonella sp 18 (15.79%), Klebsiella sp 15 (13.16%), Arcanobacterium pyogenes 11 (9.65%) in that order. Other isolates were Staphylococcus aureus 10 (8.77%), Shigella sp 8 (7.02%), Proteus vulgaris 6 (5.26%) and Streptococcus sp 4 (3.15%). The most prevalent isolate was serotyped to identify the strains of the isolate involved in diarrhoea. Serotyping of E. coli revealed the strains obtained to be 0157, 0118, 0111, 026, and 0103, with prevalence rates of 31.0%, 21.4%, 19.0%, 16.7% and 11.9% respectively. This data supports the assertion of E. coli as being the most important bacterial pathogen involved in neonatal diarrhoea or collibacillosis and have important public health implication due to the involvement of serotype O157. It was concluded that there is the need for further research to determine the presence of virulent factors of the various serotypes isolated.