Comparative transcriptome analysis of Peromyscus leucopus and C3H mice infected with the Lyme disease pathogen.

Lyme disease (LD), the most prevalent tick-borne disease of humans in the Northern Hemisphere, is caused by the spirochetal bacterium of Borreliella burgdorferi (Bb) sensu lato complex. In nature, Bb spirochetes are continuously transmitted between Ixodes ticks and mammalian or avian reservoir hosts. Peromyscus leucopus mice are considered the primary mammalian reservoir of Bb in the United States. Earlier studies demonstrated that experimentally infected P. leucopus mice do not develop disease. In contrast, C3H mice, a widely used laboratory strain of Mus musculus in the LD field, develop severe Lyme arthritis. To date, the exact tolerance mechanism of P. leucopus mice to Bb-induced infection remains unknown. To address this knowledge gap, the present study has compared spleen transcriptomes of P. leucopus and C3H/HeJ mice infected with Bb strain 297 with those of their respective uninfected controls. Overall, the data showed that the spleen transcriptome of Bb-infected P. leucopus mice was much more quiescent compared to that of the infected C3H mice. To date, the current investigation is one of the few that have examined the transcriptome response of natural reservoir hosts to Borreliella infection. Although the experimental design of this study significantly differed from those of two previous investigations, the collective results of the current and published studies have consistently demonstrated very limited transcriptomic responses of different reservoir hosts to the persistent infection of LD pathogens. Importance: The bacterium Borreliella burgdorferi (Bb) causes Lyme disease, which is one of the emerging and highly debilitating human diseases in countries of the Northern Hemisphere. In nature, Bb spirochetes are maintained between hard ticks of Ixodes spp. and mammals or birds. In the United States, the white-footed mouse, Peromyscus leucopus, is one of the main Bb reservoirs. In contrast to humans and laboratory mice (e.g., C3H mice), white-footed mice rarely develop clinical signs (disease) despite being (persistently) infected with Bb. How the white-footed mouse tolerates Bb infection is the question that the present study has attempted to address. Comparisons of genetic responses between Bb-infected and uninfected mice demonstrated that, during a long-term Bb infection, C3H mice reacted much stronger, whereas P. leucopus mice were relatively unresponsive.

Influence of closed glove exchange on bacterial contamination of the hands of the surgical team.

OBJECTIVE: To determine if closed glove exchange (CGE) increases hand contamination. STUDY DESIGN: Prospective experimental study. SAMPLE POPULATION: Surgical teams participating in 65 individual surgical procedures were included, resulting in 200 individual enrollments. METHODS: At the completion of surgery, gloves were removed and hands were swabbed. The inside of the gown cuff was swabbed. Each participant regloved, using a closed gloving technique. The new gloves were removed, and hands were swabbed for culture a second time. Swabs underwent standard bacterial culture. RESULTS: Before glove exchange, or baseline, contamination was found on 17/200 dominant hands and 13/200 nondominant hands. After performing CGE, contamination was found on 14/200 and 15/200 dominant and nondominant hands, respectively. No difference was detected between the number of CFUs cultured from a surgeon's hands before CGE and the number of CFUs cultured from a surgeon's hands post-CGE (one sided sign test, p = .61). Twelve (12) different bacterial species were identified, the most common were Staphylococcus spp. (97/154; 63%). CONCLUSION: Closed glove exchange did not increase bacterial hand contamination over baseline levels. CLINICAL SIGNIFICANCE: We found no evidence to support discontinuing CGE.

Are multiple blood cultures advantageous for canine patients?

Successful treatment of bacteremic patients depends largely on timely detection of blood-borne pathogens. Failure to detect an infection and/or contamination of blood samples can substantially delay the proper treatment. To increase the detection rate of blood-borne pathogens, well-established guidelines on blood collection and processing have been practiced in human medicine. Investigations involving human blood cultures have shown that the multiple blood sample approach significantly improves the detection rate of bacterial pathogens in the blood. Unfortunately, veterinary-specific blood culture guidelines have not been defined. Therefore, we compared detection rates of blood-borne pathogens between single and multiple blood culture approaches in a retrospective study of the clinical data from canine blood culture cases. We analyzed the data that had been collected over ~6 y and 8 mo from 177 dogs admitted to a veterinary medical teaching hospital. The triple blood culture approach increased the detection rate of blood-borne pathogens by 19.5% compared to single sampling. The optimal timing between multiple sample collections remains to be determined.

Testing Raman spectroscopy as a diagnostic approach for Lyme disease patients.

Lyme disease (LD), the leading tick-borne disease in the Northern hemisphere, is caused by spirochetes of several genospecies of the Borreliella burgdorferi sensu lato complex. LD is a multi-systemic and highly debilitating illness that is notoriously challenging to diagnose. The main drawbacks of the two-tiered serology, the only approved diagnostic test in the United States, include poor sensitivity, background seropositivity, and cross-reactivity. Recently, Raman spectroscopy (RS) was examined for its LD diagnostic utility by our earlier proof-of-concept study. The previous investigation analyzed the blood from mice that were infected with 297 and B31 strains of Borreliella burgdorferi sensu stricto (s.s.). The selected strains represented two out of the three major clades of B. burgdorferi s.s. isolates found in the United States. The obtained results were encouraging and prompted us to further investigate the RS diagnostic capacity for LD in this study. The present investigation has analyzed blood of mice infected with European genospecies, Borreliella afzelii or Borreliella garinii, or B. burgdorferi N40, a strain of the third major class of B. burgdorferi s.s. in the United States. Moreover, 90 human serum samples that originated from LD-confirmed, LD-negative, and LD-probable human patients were also analyzed by RS. The overall results demonstrated that blood samples from Borreliella-infected mice were identified with 96% accuracy, 94% sensitivity, and 100% specificity. Furthermore, human blood samples were analyzed with 88% accuracy, 85% sensitivity, and 90% specificity. Together, the current data indicate that RS should be further explored as a potential diagnostic test for LD patients.

The Microbiota of Ixodes ricinus and Dermacentor reticulatus Ticks Collected from a Highly Populated City of Eastern Europe.

Recent investigations have examined, through sequencing the V6 region of 16S rRNA gene, the microbiota of questing Ixodes ricinus and Dermacentor reticulatus ticks collected from rural areas of Central (Dnipropetrovs'k (region D) and Poltava (region P)) and Northeastern (Kharkiv (region K)) Ukraine. In addition to defining the bacterial microbiota of both tick species, the previous investigations also revealed a high degree of inter-sex and inter-regional variations in the tick microbiota. As a continuation of the two studies, the present investigation has analyzed individual microbiota of questing I. ricinus (n = 50) and D. reticulatus (n = 50) ticks originating from Kyiv, the largest city of Ukraine. The Kyiv tick microbiota were compared between males and females for each tick species. Additionally, a cross-regional analysis was performed to compare the microbiota of Kyiv ticks to those from regions D, K, and P. Numerous statistically significant inter-sex and inter-regional variations were detected when alpha diversity, beta diversity, the bacterial relative and differential abundances were assessed. The overall results demonstrated that the microbiota of Kyiv ticks were statistically different compared to the ticks of the other three regions. Besides existing climatic and geographical differences between the four regions, the authors hypothesize that various anthropogenic factors of the megapolis (e.g., animal species translocation, land management, ecology) could have contributed to the distinct microbiota of Kyiv ticks observed in this study.

Comparison of bacteriologic culture results for skin wound swabs and skin wound biopsy specimens.

OBJECTIVE: To compare bacteriologic culture results for superficial swab and tissue biopsy specimens obtained from dogs with open skin wounds. ANIMALS: 52 client-owned dogs. PROCEDURES: For each dog, 1 wound underwent routine preparation prior to collection of 2 specimens, 1 by superficial swab (Levine) technique and 1 by tissue biopsy. Specimens were processed for bacteriologic culture. Two observers determined whether any detected difference in culture results for the 2 types of specimen would have resulted in differing treatment plans. RESULTS: Culture results of swab and tissue biopsy specimens were identical in 11/52 (21.2%) cases. Tissue biopsy specimen and swab cultures yielded positive results for 44 (84.6%) and 40 (76.9%) wounds, respectively. With regard to mean recovery rates of bacteria from wounds with positive culture results, both the biopsy specimens and swabs yielded 3.4 bacterial species/wound. All wounds for which swab cultures yielded no growth also had negative culture results for biopsy specimens. Biopsy specimen and swab culture results were in agreement with regard to the most common bacteria cultured. In 7/52 (13%) wounds, the observers would have treated the patient differently on the basis of the results of the 2 cultures. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that culture of a swab collected by the Levine technique is an appropriate noninvasive alternative to culture of a tissue biopsy specimen. A negative result obtained from culture of a swab is likely to be reliable. Disagreement between the results of swab and tissue biopsy specimen cultures is likely of low clinical importance.

Stray Mexico origin cattle captured crossing into Southern Texas carry Babesia bovis and other tick-borne pathogens.

Cattle fever ticks, Rhipicephalus microplus and R. annulatus have been eradicated from the United States and inspectors from the U.S. Department of Agriculture (USDA), Animal Plant Health Inspection Service (APHIS), Cattle Fever Tick Eradication Program (CFTEP) monitor the quarantine zone along the Texas border to prevent the introduction of livestock carrying cattle fever ticks from Mexico. Stray livestock apprehended by CFTEP in the zone are checked for ticks and tested for infectious disease-causing pathogens but are not evaluated for evidence of infection with tick-borne pathogens. We tested blood samples collected from stray cattle by CFTEP inspectors for evidence of infection with tick-borne pathogens. As a comparison group representing U.S. resident cattle, we tested blood samples that had been sent to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for unrelated testing. Both sets of blood samples were evaluated using the same specific and broad-spectrum PCR assays. For the border cattle the overall prevalence of infection with one or more tick-borne pathogen was 58.5 % (79/135) with many co-infections, including 30 cattle positive for Babesia bovis and/or Babesia bigemina (22.2 %) and 77 cattle positive for Anaplasma marginale (57 %), three of these animals were also positive for Borrelia theileri. No resident cattle represented by the TVMDL samples were infected with either of the Babesia spp., or with Borrelia theileri, but three were positive for Theileria orientalis and 7.3 % (7/96) were positive for A. marginale. These data show that cattle originating in Mexico have a higher prevalence of infection with tick-borne pathogens relative to resident U.S. cattle and specifically, a proportion are infected with bovine Babesia, which is absent from U.S. cattle populations. Consequently, these stray cattle may be a reservoir of tick-borne pathogens and if populations of Boophilus ticks become reestablished in areas where they had previously been eradicated, could pose a significant risk to the U.S. Cattle industry.

Extensive sex-specific and regional variations observed in the microbiome of Dermacentor reticulatus.

Recent progress in DNA sequencing technologies and advanced bioinformatic tools have enabled researchers to rapidly decipher the tick microbiome. To date, however, a number of microbiome studies performed on Dermacentor reticulatus ticks is still quite limited. Despite the importance of this ixodid tick for veterinary and human medicine, only two investigations have examined its microbiome. Moreover, these studies analyzed only a limited number of ticks/tick pools. Given the scarcity of microbiome data for D. reticulatus in general and the lack of microbiome studies on tick species from Eastern Europe in particular, the objective of the current investigation was to analyze the microbiome of D. reticulatus ticks collected from three geographical regions of Ukraine. A total of 88 individual tick microbiomes were analyzed by sequencing the V6 region of 16S rRNA. As a result, numerous significant differences in the bacterial relative abundance were detected between males and females of D. reticulatus for each region. The alpha diversity measures indicate that microbiomes were significantly different between females of D. reticulatus inter-regionally. In contrast, the collective results for male ticks are more suggestive of inter-regional microbiome homogeneity. The overall findings indicate that the composition and diversity of the D. reticulatus microbiome can be impacted by geographical and sex-related factors.

Metagenomic analysis of individually analyzed ticks from Eastern Europe demonstrates regional and sex-dependent differences in the microbiota of Ixodes ricinus.

Understanding the microbial ecology of disease vectors may be useful for development of novel strategies aimed at preventing transmission of vector-borne pathogens. Although Ixodes ricinus is one of the most important tick vectors, the microbiota of this tick has been examined for only limited parts of the globe. To date, the microbiota of I. ricinus ticks collected from Eastern Europe has not been defined. The objective of this study was to compare microbiota of I. ricinus ticks within (males vs. females) and between collection sites that represented three administrative regions of Ukraine, Dnipropetrovs'k (D), Kharkiv (K), and Poltava (P). A total of 89 questing I. ricinus adults were collected from region D (number of ticks, n = 29; 14 males and 15 females), region K (n = 30; 15 males and 15 females) and region P (n = 30; 15 males and 15 females). Each tick was subjected to metagenomic analysis by targeting the V6 region of 16S rRNA gene through the Illumina 4000 Hiseq sequencing. The alpha diversity analysis demonstrated that, regardless of tick sex, patterns of bacterial diversity in ticks from regions K and P were similar, whereas the microbiota of region D ticks was quite distinct. A number of inter-regional differences were detected by most beta diversity metrics for both males and females. The inter-regional variations were also supported by the principal coordinate analysis based on the unweighted UniFrac metrics with three region-specific clusters of female ticks and one distinct cluster of region D males. Lastly, numerous region- and sex-specific differences were also identified in the relative abundance of various bacterial taxa. Collectively, the present findings demonstrate that the microbiota of the I. ricinus tick can exhibit a high degree of variation between tick sexes and geographical regions.

The First Immunocompetent Mouse Model of Strictly Human Pathogen, Borrelia recurrentis.

The spirochetal bacterium Borrelia recurrentis causes louse-borne relapsing fever (LBRF). B. recurrentis is unique because, as opposed to other Borrelia spirochetes, this strictly human pathogen is transmitted by lice. Despite the high mortality and historically proven epidemic potential and current outbreaks in African countries and Western Europe, research on LBRF has been obstructed by the lack of suitable animal models. The previously used grivet monkey model is associated with ethical concerns, among other issues. An existing immunodeficient mouse model does not limit bacteremia due to its impaired immune system. In this study, we used genetically diverse Collaborative Cross (CC) lines to develop the first LBRF immunocompetent mouse model. Out of 12 CC lines tested, CC046 mice consistently developed B. recurrentis-induced spirochetemia during the first 3 days postchallenge as concordantly detected by dark-field microscopy, culture, and quantitative PCR. However, spirochetemia was not detected from day 4 through day 10 postchallenge. The high-level spirochetemia (>107 cells/ml of blood) observed in CC046 mice was similar to that recorded in LBRF patients as well as immunocompetent mouse strains experimentally infected by tick-borne relapsing fever (RF) spirochetes, Borrelia hermsii and Borrelia persica. In contrast to the Old World and New World RF spirochetes, which develop multiple relapses (n = 3 to 9), B. recurrentis produced only single culture-detectable spirochetemia in CC046 mice. The lack of relapses may not be surprising, as LBRF patients and the grivet monkey model usually develop no or only 1 to 2 spirochetemic relapses. The novel model will now allow scientists to study B. recurrentis in the context of intact immunity.

Serological Surveillance of Hospitalized Patients for Lyme Borreliosis in Ukraine.

Objectives: Although in Ukraine the incidence of Lyme borreliosis (LB) has been surging up over the past decades, seroepidemiologic data are not available to date. The objective of this report was to perform preliminary serological survey of hospitalized population for LB. Methods: Sera were collected from 203 patients of a hospital located in Western Ukraine. Most patients showed clinical signs that were compatible with LB such as arthritis (n = 29), neurological signs (n = 35), and erythema migrans (EM)-like lesions (n = 60) or unrelated to LB (n = 79). The specimens were tested by enzyme-linked immunosorbent assay and Western blot for anti-Borrelia antibodies. Results: LB was confirmed in 8.6%, 34.5%, and 50% of the patients, who exhibited neurological signs, arthritis, or EM-like lesions, respectively. Anti-Borrelia antibodies were also detected in 6.3% of the patients with pulmonary tuberculosis. Conclusions: This study provides the first preliminary data on the seroprevalence of LB in Ukraine. Future studies are warranted to investigate more subsets of the Ukrainian population for this emerging tick-borne disease.

Phylogenetic analysis of tick-borne encephalitis virus strains found in an engorged tick and traveler returning from Russia.

Although travel-related tick-borne encephalitis (TBE) cases have been increasingly registered worldwide, very few published case studies are available to date. The present report describes a travel-related TBE case and provides genotypic characterization of two viral isolates. Laboratory diagnostics were based on complement fixation test and virus isolation. This report is unique because the TBE case was first confirmed by virus isolation from the engorged tick and only later from the patient's blood. Moreover, this case demonstrated a successful prophylaxis performed on day 8 post tick exposure although it is generally recommended that anti-TBEV immunoglobulins should be administered not later than on day 4 after tick bite. Sequences of E protein gene fragments were used to phylogenetically characterize the two isolates. The results demonstrated that both viral isolates belonged to clusteron 3A (Zausaev group) of the Asian lineage of the TBEV Siberian subtype. The synonymous nucleotide substitution, C351 T, was identified in E protein gene fragments of TBEV 88 and TBEV 89, which could have been induced by virus transmission. A few important take-home messages can be gleaned from the reported case. First, travelers should be aware of TBE endemic areas that they plan to visit and be proactive when exposed to Ixodes ticks. Second, medical practitioners should always consider travel history and potential tick exposure of patients. Lastly, engorged Ixodes spp. ticks removed from the patients, who have arrived from endemic areas, should be tested for TBEV even in the absence of TBE clinical signs.

Exploring a possibility of using Raman spectroscopy for detection of Lyme disease.

Lyme disease (LD), one of the most prevalent tick-borne diseases in the United States (US), is caused by Borreliella burgdorferi sensu stricto (Bb). To date, in the US, LD diagnostics is primarily based on validated two-tiered serological testing, which overall exhibits low sensitivity among other drawbacks. In the present study, a potential of Raman spectroscopy (RS) to detect Bb infection in mice has been explored. For that, C3H mice were infected with wild-type Bb strains, 297, B31, or B31-derived mutant, ∆vlsE. Blood samples taken prior to and post Bb infection were subjected to RS. The data demonstrated that RS did not directly detect Bb spirochetes in blood, but rather sensed biochemical changes associated with Bb infection. Despite Bb infection-associated blood changes detectable by RS were very limited, the partial least square discriminant analysis showed that the average true positive rates were 86% for 297 and 89% for B31 and ∆vlsE.

Prevalence of Borrelia burgdorferi and Anaplasma phagocytophilum in Ixodid Ticks from Southeastern Ukraine.

Objectives: Tick-borne diseases have emerged as an increasing medical problem in the world. Being the most prevalent ixodid ticks in Europe, Ixodes ricinus and Dermacentor reticulatus are responsible for transmission of numerous zoonotic pathogens (e.g., human granulocytic anaplasmosis and Lyme borreliosis). Despite their public health significance, studies on the prevalence of tick-borne agents are scare for Eastern Europe. The objective of this study was to examine the prevalence of Anaplasma phagocytophilum, Ehrlichia chaffeensis, and Borrelia burgdorferi sensu lato (B. burgdorferi s. l.) in ixodid ticks from Southeastern Ukraine. Methods: Over a 5-year period (2014-2018), 358 questing and 389 engorged ixodid ticks were collected from Southeastern Ukraine (Zaporizhzhya region). The ticks were identified as Dermacentor marginatus, D. reticulatus, I. ricinus, and Rhipicephalus rossicus. Nucleic acid samples extracted from tick pools were subjected to RT-PCR analyses for A. phagocytophilum, E. chaffeensis, and B. burgdorferi s. l. Results: The examined ixodid ticks tested negative for the aforementioned pathogens with the exception of I. ricinus ticks. For questing I. ricinus ticks, minimum infection rates of A. phagocytophilum and B. burgdorferi s. l. were, respectively, 4.2-7.7% and 8.6-12.7%. Conclusions: These findings will be valuable for medical and veterinary practitioners when risks associated with tick-borne diseases are assessed for southeastern regions of Ukraine.

Detection of pathogens in ixodid ticks collected from animals and vegetation in five regions of Ukraine.

The distribution and prevalence of zoonotic pathogens infecting ixodid ticks in Western Europe have been extensively examined. However, data on ticks and tick-borne pathogens in Eastern Europe, particularly Ukraine are scarce. The objective of the current study was, therefore, to investigate the prevalence of Anaplasma phagocytophilum, Anaplasmataceae, Rickettsia spp., Babesia spp., Bartonella spp., and Borrelia burgdorferi sensu lato in engorged and questing ixodid ticks collected from five administrative regions (oblasts) of Ukraine, namely Chernivtsi, Khmelnytskyi, Kyiv, Ternopil, and Vinnytsia. The ticks were collected from both wild and domestic animals and from vegetation. Of 524 ixodid ticks collected, 3, 99, and 422 ticks were identified as Ixodes hexagonus, Ixodes ricinus, and Dermacentor reticulatus, respectively. DNA samples individually extracted from 168 questing and 354 engorged adult ticks were subjected to pathogen-specific PCR analyses. The mean prevalence in I. ricinus and D. reticulatus were, respectively: 10 % (10/97) and 3 % (12/422) for A. phagocytophilum; 69 % (67/97) and 52 % (220/422) for members of the Anaplasmataceae family; 25 % (24/97) and 28 % (117/422) for Rickettsia spp.; 3 % (3/97) and 1 % (6/422) for Babesia spp.; and 9 % (9/97) and 5 % (20/422) for Bartonella spp. Overall, between the five cities, there was no significant difference in the prevalence of any of the pathogens for the respective ticks (p > 0.05). The prevalence of B. burgdorferi s. l. in the questing and engorged I. ricinus varied from 0 to 27 % and 14-44%, respectively, with no statistical significance identified between the five cities (p > 0.05). In addition to reporting the updated data for Kyiv and Ternopil, this study is the first to provide the prevalences of the tick-borne pathogens for Chernivtsi, Khmelnytskyi, and Vinnytsia. This investigation is also the first to detect Neoehrlichia mikurensis in ixodid ticks from Ukraine. These new data will be useful for medical and veterinary practitioners as well as public health officials when diagnosing infections and when implementing measures to combat tick-borne diseases in Ukraine.

Serological prevalence of six vector-borne pathogens in dogs presented for elective ovariohysterectomy or castration in the South central region of Texas.

BACKGROUND: Most vector-borne pathogens cause zoonotic diseases. These zoonoses often have wild animal reservoirs that play a significant role in disease epidemiology. However, pet animals have also been implicated in transmission of zoonotic agents to humans. To exemplify, dogs are competent reservoir hosts for several zoonotic vector-borne bacteria and protozoa. Despite that vector-borne diseases can be life-threatening for both pets and humans, studies on pathogen seroprevalence are very limited. Therefore, the objective of this study was to determine the serological prevalence of six zoonotic vector-borne agents in dogs from the South Central region of Texas (US). Electronic medical records of dogs, presenting over 2014-2019 for elective ovariohysterectomy or castration at a high volume spay and neuter clinic, were reviewed for serological testing. Sera from 418 dogs were tested for the Dirofilaria immitis antigen, and antibodies to Anaplasma phagocytophilum, Anaplasma platys, Borrelia burgdorferi, Ehrlichia canis, and Ehrlichia ewingi, using a commonly available commercial test kit. Descriptive statistics were computed to characterize the respective seroprevalence rates of the dog population. The study involved 192 (46%) male and 226 (54%) female dogs. RESULTS: Overall, 85 (20%) dogs tested positive for at least one of the 6 pathogens investigated. The highest seroprevalence rate averaged over the 6-year period was 11.7% for D. immitis followed by 8.4% for E. canis and/or E. ewingii, 4.3% for A. phagocytophilum and/or A. platys, and 0.2% for B. burgdorferi. The co-exposure or co-infection was only detected in 3.8% of the dog population. CONCLUSIONS: Together, opportunistic testing of dogs presenting for elective surgical procedures may provide an effective way of assessing seroprevalence and/or risk factors for common vector-borne diseases within a geographic region of concern.

Antimicrobial Susceptibility of Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli Isolated from Mastitic Dairy Cattle in Ukraine.

Bovine mastitis is the predominant cause for antimicrobial use on dairy farms and is a major source of economic losses in the dairy industry. In this study, the antimicrobial susceptibility profiles of common mastitis-causing pathogens, Staphylococcus aureus (n = 62), Streptococcus agalactiae (n = 46), and Escherichia coli (n = 129), were determined for dairy cattle with mastitis across 142 Ukrainian farms. The results showed that there were more gentamicin resistant S. aureus isolates (16.95%) identified in this study than previously reported for Ukrainian dairy cattle. Moreover, low levels of amoxicillin susceptibly (13.51%) were observed for St. agalactiae, which contrasted a previous study showing susceptibility levels of >50%. St. agalactiae resistance to tetracycline was observed in 80% of the isolates. Cephalosporin use was most ineffective against E. coli, with 43.27-56% of the isolates exhibiting this resistant trait. Overall, this study performed a preliminary analysis of antimicrobial resistance on mastitis isolates from Ukrainian farms. However, given the limited numbers of the isolates tested in this study and that the publications on antimicrobial resistance in animal husbandry of Ukraine are very few, more extensive investigations are needed to comprehensively examine susceptibility patterns of mastitis-causing pathogens in dairy cattle in Ukraine.