Isolation and Identification of Pyogenic Bacteria from Cutaneous Abscesses in Goats

Abstract

Background: Cutaneous abscesses are common infections that seriously affect the quality and yield of goat breeding. The main pathogens that cause cutaneous abscesses are well understood; however, the associated microbial community remains relatively unknown. Aim:  This study showed that caprine cutaneous abscesses in the examined goats were associated with septic bacterial infection, occurring as both single and mixed infections. Methods: To determine the different types of microorganisms present in caprine cutaneous abscesses, 30 pus samples collected from different goat farms in the Jabalpur region, India, were subjected to isolation, identification and antibiotic sensitivity testing (ABST). Results: The microbial communities of each sample contained about 6-8 microbial species. Each sample contained different microorganisms or combinations of species, including Corynebacterium, Staphylococcus, Streptococcus, Pseudomonas, Klebsiella and E. coli. The bacteria were identified by their colony characteristics and microscopic examination, including Gram staining for bacteriological study and Giemsa staining for cytology. Out of 30 samples, 20 (66.67%) yielded single bacteria comprising three genera of Gram-positive bacteria (08 Corynebacterium spp., 05 Staphylococcus spp. and 02 Streptococcus spp.) and three genera of Gram-negative bacteria (02 Pseudomonas spp., 02 Klebsiella spp. and 01 Escherichia coli). In 10 goats (33.33%), multiple bacteria were obtained in different combinations. Based on Gram staining, the proportion of Gram-positive bacteria dominated over Gram-negative bacteria in both single and mixed isolates. The bacterial isolates were further subjected to biochemical tests (catalase, coagulase, oxidase, urease and IMViC). In antibiotic sensitivity testing, Corynebacterium spp. was sensitive to Amikacin, Ciprofloxacin, Enrofloxacin, Gentamicin, Amoxiclav, Erythromycin and Tetracycline, while Staphylococcus spp. was sensitive to Ceftriaxone, Gentamicin, Meropenem and Streptomycin. Conclusion: The prevalence of caprine cutaneous abscesses was determined as 12.56% during the seven-month study period. All caprine cutaneous abscesses were septic, with single or multiple bacterial infections. The most prevalent bacterium was Corynebacterium spp. (26.66%), followed by Staphylococcus spp. (16.66%). Tetracycline and Gentamicin were found to be most effective against Corynebacterium spp. and Staphylococcus spp., respectively. However, Meropenem was found to be sensitive against most of the isolated bacterial spp.