Etiology and antibiotic susceptibility of bacteria causing cervical Lymphadenitis in clinically ill breeding Guinea Pigs (Cavia porcellus)

Lymphadenitis in Guinea Pig –GP– (Cavia porcellus) is of clinical importance, but its etiology and therapeutic treatments remain insufficient in the field of Veterinary Medicine, therefore the etiology and antibiotic susceptibility of bacteria causing cervical lymphadenitis (CL) in clinically ill breeding GP was investigated. It was worked with 50 Peru breed GP, clinically affected by this disease (25 with external abscesses and 25 with internal abscesses). Twentyfive independent lymph node aspiration samples were taken from each group. The samples were cultured in ABS, TSA, BHI media, supplemented with alpaca blood, enriched with FTM broth and incubated at 37 °C for 48 hours. The identification of the bacteria was done through morphological and microscopic characterization, Camp’s test and biochemistry. Antibiotic susceptibility was evaluated using the Kirby-Bauer method using six common antibiotics on the Veterinary market. High frequencies of Streptobacillus moniliformis (100 and 96%), Streptococcus pyogenes (96 and 100%), Streptococcus zooepidemicus (96 and 92%) were found, with a close association between the three bacteria for external and internal abscesses and with the presence of multiple antibiotic resistance to more than three antibiotics (Ampicillin, Oxytetracycline, Amoxicillin, Chloramphenicol), with sensitivity response to Penicillin (26-29%) and Gentamicin (23-26%) as possible therapeutic success. External and internal subcutaneous abscesses with CL in C showed predominance of Gram-negative bacteria S. moniliformis, S. pyogenes and multidrugresistant S. zooepidemicus with high frequencies.