Gram-positive aerobic and microaerophilic microorganisms isolated from pathological processes and lesions of horses

Abstract

ABSTRACT:The aim of this study was to characterise the genera and species of Gram-positive aerobic and microaerophilic microorganisms isolated from pathological processes and lesions in horses. In the period 2009-2014, 449 clinical samples from horses were examined. Of these, 229 (51%) were collected from the respiratory tract, 121 (26.9%) from the skin, 40 (8.9%) from the gastrointestinal tract, 40 (8.9%) from the eyes, 8 (1.8%) from the urinary tract, 6 (1.3%) from the musculoskeletal system, 4 (0.9%) from the lymphatic system and 1 (0.2%) from milk. The isolates were presumptively identified phenotypically, and identification was confirmed by molecular phenotypic MALDI-TOF. The most frequently detected strains (n = 330) were Staphylococcus spp., Streptococcus spp., Corynebacterium spp. with prevalence rates of 37.2%, 23.4% and 7.6%, respectively. In addition, 24 other taxa were identified, including Enterococcus spp., Bacillus spp., Trueperella pyogenes, Aerococcus viridans, Dermatophilus congolensis, Lysinibacillus fusiformis, Nocardiopsis alba and Streptomyces spp. Most of these are described as opportunistic pathogens of animals, including horses. Antibiotic susceptibility was tested using the disc diffusion method. Florfenicol and amoxycillin with clavulanic acid were the most effective antibiotics. The susceptibility to florfenicol was 100% for tested strains of Bacillus spp., Lysinibacillus spp., Corynebacterium spp., Dermatophilus congolensis, Streptococcus spp., Enterococcus spp., Aerococcus spp., Nocardiopsis alba and Trueperella pyogenes. The susceptibilities of Staphylococcus aureus and other staphylococci to florfenicol were 96.2% and 98.5% in tested strains, respectively. Amoxycillin with clavulanic acid exhibited 100% effectiveness against Corynebacterium spp., Dermatophilus congolensis, Streptococcus spp., Aerococcus spp., Enterococcus spp., Streptomyces spp., Nocardiopsis alba and Trueperella pyogenes tested strains. The susceptibilities of Staphylococcus aureus, other staphylococci and Bacillus/Lysinibacillus spp. to amoxycillin with clavulanic acid were 89.8%, 98.8% and 20.0% of tested strains, respectively.

Safkan İngiliz ve Arap Yarış Atlarında Görülen Beta Hemolitik Streptococcus Türlerinin Sitolojik Bulgular Eşliğinde Çeşitli Vücut Bölgelerinden İzolasyonu ve Antibiyotik Duyarlılıkları

“…zooepidemicus probably causes more disease in the horse than any other infectious agent yet [6] . S. zooepidemicus was the most isolated microorganism (72.0%) followed by S. equisimilis (21.3%), S. equi (5.8%) and unidentified beta hemolytic streptococci (0.9%) in a previous study and in different studies such as 56.4% [1] and 87.2% [5] amongst beta hemolytic streptococci. The agent was isolated 81.0% and 84.2% from respiratory tract of adult horses and foals respectively in the same study [3] .…”

“…Ampicillin, gentamicin, neomycin, oxytetracycline, penicillin G, trimethoprim/sulfamethoxazole yielded 100%, 19%, 13%, 29%, 100% and 90% efficacy against beta hemolytic streptococcal isolates in a different study respectively [4] . Penicillin showed 100% efficacy against S. equisimilis, S. equi and S. zooepidemicus [1] . The efficacy of streptomycin were determined as 33.3%, 0%, and 10.0%, neomycin 50.0%, 0% and 23.5%, gentamicin 100%, 100% and 97.4%, tetracycline 47.1%, 60.0% and 60.0%, amoxicillin/clavulanic 100% against the three pathogens, while the efficacy of enrofloxacin was found to be 73.3%, 81.8% and 86.8% against S. equisimilis, S. equi and S. zooepidemicus respectively in the same study [1] .…”

“…Penicillin showed 100% efficacy against S. equisimilis, S. equi and S. zooepidemicus [1] . The efficacy of streptomycin were determined as 33.3%, 0%, and 10.0%, neomycin 50.0%, 0% and 23.5%, gentamicin 100%, 100% and 97.4%, tetracycline 47.1%, 60.0% and 60.0%, amoxicillin/clavulanic 100% against the three pathogens, while the efficacy of enrofloxacin was found to be 73.3%, 81.8% and 86.8% against S. equisimilis, S. equi and S. zooepidemicus respectively in the same study [1] . Erol et al [3] reported that gentamicin efficacy was 83.3%, 82.8% and 87.5% against S. equi, S. equisimilis and S. zooepidemicus respectively where penicillin efficacy was found to be 98.7%, 99.2%, 98.9%, tetracycline efficacy was found to be 98.8%, 50.9%, 44.0% and trimethoprim/sulfamethoxazole efficacy was found to be 50.2%, 94.4%, 30.9% against the same agents respectively.…”

“…Beta hemolytic Streptococcus spp., which produce complete clearing of blood agar medium due to lysis of erythrocytes in media, are the most important and widespread agents causing infectious diseases in horses [1] . Of the beta hemolytic streptococci species Streptococcus equi subsp.…”

“…S. equi was also isolated from intra-uterine swabs (3.2%) [4] , lower respiratory tract of foals (6.3%), adult horses (6.2%), lymph node abscess of foals (41.9%), adults (49.6%) and total isolation rate was found to be 6.3% in the same study [3] . S. equi was isolated 15.5% [1] and 12.8% [5] from various body sites of the horses in different studies.…”