Agentes patógenos y resistencia bacteriana en dermatopatías de canis lupus familiaris atendidos en clínicas veterinarias de la ciudad de Machala

Abstract

The skin of canines is exposed to various pathogens that can cause different lesions that produce an imbalance that affects the normal structure of the skin, presenting dermatopathies that are very common in the field of Veterinary Medicine. That is why different diagnostic methods must be performed to discover the cause of the disease, among which we have: trichogram, scrapings, swabs, cultures. This research work aims to diagnose pathogens and study the bacterial resistance of dermatopathies that occur in canines, for which different diagnostic methods were used, laboratory tests were carried out in order to identify bacteria and measure sensitivity and / or resistance thereof. To start with the investigative work, samples were taken in dogs with recurrences attended at the different veterinary clinics in the city of Machala, to which the necessary materials were taken to collect the sample and a dermatological file for each patient who presented skin lesions. Once the samples were collected, they were transferred and processed in the laboratory of the Faculty of Agricultural Sciences of the Technical University of Machala (in Microbiology laboratory 2) using the different diagnostic tests. Subsequently, samples of hair were analyzed for the trichogram and the cultivation of fungi, scrapings were also performed to identify the presence of mites and swabs for the cultivation of bacteria. The samples of deep scrapings were observed under the microscope obtaining few positive results for mites, in the analysis of the trichogram we observed hairs broken due to the itching and a large number of hairs in the telogenic phase of which it was seeded to determine the presence of pathogenic dermatophytes, obtaining negative results since when carrying out the microscopic observation of the fungi that grew in the culture media, these were environmental fungi. Blood agar and chocolate agar were used in the bacterial cultures, of which hemolytic and non-hemolytic bacteria were observed. Then the catalase test was carried out to differentiate the samples of Staphylococcus and Streptococcus bacteria, being this positive for Staphylococcus, immediately the Gram stain was done in order to confirm the presence of Staphylococcus by microscopic observation and identify if these were Gram positive o Gram negative. When seeding on mannitol agar, Staphylococcus aureus was identified since a change in color of the medium from red to yellow was observed and Staphylococcus pseudintermedius maintained the color of the medium. Once the bacteria were identified and isolated, the antibiogram was carried out taking into account the patients with recurrences. Of all the dogs evaluated, 4 still maintained the dermatological problem. Prior to this, a suspension was prepared with the bacterial colonies at a concentration of 0.5 on the Mc Farland scale. Cefoxitin and oxacillin disks were used for the antibiogram; for S. aureus the cefoxitin disc and for S. pseudintermedius the oxacillin disc. Resistance was obtained in two samples representing 7.69% of all samples in which there was bacterial growth.