A one-year descriptive epidemiology of zoonotic abortifacient pathogen bacteria in farm animals in Turkey.

This study aimed to investigate the epidemiology of 10 suspicious pathogenic bacteria in 250 stomach contents of aborted calf, lamb, and goat foetuses in 2019. The 155 positive samples obtained from PCR consisted of 53 (58.88 %) bacteria from 90 lamb samples, 10 (43.47 %) bacteria from 23 goat samples, and 92 (67.15 %) bacteria from 137 calf samples. The five most common bacteria associated with abortions were Brucella melitensis, 52 (20.9 %); B. abortus, 13 (5.2 %); Leptospira spp., 34 (13.6 %); Campylobacter fetus, 52 (20.9 %); and Coxiella burnetii, 4 (1.6 %). The highest rate of B. melitensis (65.4 %), B. abortus (69.2 %), Leptospira spp. (67.6 %), and C. fetus (50 %) was detected in the aborted calf samples. The highest individual rate was that of C. fetus (5.2 %). The flock-herd rates of B. melitensis, B. abortus, Leptospira spp., C. fetus, and C. burnetii infections in the 29 farms studied were 34.48 %, 20.69 %, 62.06 %, 82.75 %, and 3.44 %, respectively, with a confidence level and interval of 95 %. The frequency of abortions caused by Leptospira spp. and Campylobacter fetus may be related to increasing in B. melitensis. The rates of aborted calf, lamb, and goat foetuses among the various sampling periods and regions were significantly (P < 0.01) different. In conclusion, precautions should be applied to reduce the spread of these bacterial agents in high-risk areas and to eliminate the risk of harbouring these zoonotic infections in humans. Therefore, these results must be taken into account in the development of control and protection strategies against abortions in animals.

Evaluation of Boron's Adjuvant Activity in Inactive Bacterin Vaccines Using the Mice Model.

Vaccination is the most effective, reliable, and economical way of preventing or reducing the effect of infectious diseases. When preparing inactive vaccines, a range of additives called adjuvants are necessary to enhance the magnitude of the immune response. Boron has a wide range of industrial and medical applications, and its positive effects on distinct functions have been described in plants, humans, and animals. However, no studies exist about the possible adjuvant activities of boron compounds in vaccines. Hence, in this study, the potential adjuvant effect of boric acid was explored and compared with common veterinary adjuvants in a mice model. Staphylococcus aureus (S. aureus) used as vaccine antigen was isolated from dairy cows with bovine mastitis. Vaccines adjuvanted with boric acid, aluminum hydroxide, Montanide ISA 50 and ISA 206, and Montanide + boric acid combinations were prepared. The efficacy of vaccines was evaluated according to local reactions at the injection site, C-reactive protein, total Ig G, total Ig M, and anti-S. aureus antibody levels in mice. Boric acid reduced local inflammatory reactions induced by the Montanide adjuvants. Moreover, mice vaccinated with boric acid-adjuvanted vaccine had higher levels of anti-S. aureus antibody than those in the controls (P < 0.05) and were similar to the levels found in mice sensitized with aluminum hydroxide. Total Ig G and Ig M results were, however, unsuitable for the assessment of adjuvant activity for this study. In conclusion, this study revealed that boric acid has an adjuvant potential in inactive bacterin vaccines, but further target animal studies are needed.

Evaluation of random amplified polymorphic DNA and multiple-locus variable number tandem repeat analyses for Mycoplasma cynos.

Mycoplasma spp. can cause diseases of the respiratory system as well as urogenital infections, infertility, and anemia. The members of this genus have a low G + C content compared to other bacteria. Because primers used in the random amplified polymorphic DNA (RAPD) technique are only 10 bp long and have high GC content, this method can be inadequate for genotyping Mycoplasma spp. isolates. The aim of this study was to develop and evaluate multiple-locus variable number tandem repeat analysis (MLVA) and two-primer RAPD (TP-RAPD) procedures for subtyping Mycoplasma cynos isolates. A total of 55 M. cynos isolates obtained from 162 bronchoalveolar lavage fluid samples from shelter and pet dogs were used in this study. Seventy-four tandem repeat regions were detected in the M. cynos genome, and two of these loci were determined to be suitable and used for development of the MLVA scheme. The results of variable number tandem repeat (VNTR) analysis and TP-RAPD-PCR were compared with RAPD-PCR. The discriminatory power of TP-RAPD-PCR (Hunter-Gaston diversity index [HGDI] = 0.84) was higher than those of RAPD-PCR (HGDI = 0.727), VNTR1 (HGDI = 0.8), and VNTR3 (HGDI = 0.757). We observed that the TP-RAPD-PCR and MLVA methods provide clearer data and are more successful in determining genetic diversity, in contrast to the RAPD-PCR method for this species.

Comparison of five methods for isolation of DNA from Mycoplasma cynos.

Extraction of DNA from Mycoplasma cultured on agar medium is difficult because the plasticity of these microorganisms enables agar penetration. This eventually causes cell loss during harvesting of colonies from the agar surface. Here, we used the GenElute™ gel extraction kit, which is usually used to purify polymerase chain reaction products, for extracting DNA from Mycoplasma. We compared the DNA extraction efficiency of the GenElute™ gel extraction kit from Mycoplasma cynos cultured in agar medium with four other DNA extraction methods. The results were evaluated based on the purity and amount of DNA obtained from one Mycoplasma colony. Eight strains of Mycoplasma cynos isolated from the broncho-alveolar lavage fluid of dogs were used. The GenElute™ gel extraction protocol was the most efficient among all the methods tested in this study as it yielded the highest amount and the purest quality of DNA (199.3±0.744ng/µl) from a single colony. Among the methods tested, the GenElute™ gel extraction method is the most rapid, sensitive, and simple method for DNA extraction from Mycoplasma. This procedure may also prove useful for extracting DNA from other Mycoplasma species.

Antibacterial and Antibiofilm Effects of Boron on Different Bacteria.

Boron (B) compounds are used in many fields ranging from medicine to industry. In this study, boric acid (BA) and disodium octaborate tetrahydrate (DOT) were evaluated for their antibacterial effects and antibiofilm capacities on selected strains of clinical and type cultures that are of veterinary concern (Staphylococcus aureus ATCC 25923, Aeromonas hydrophila ATCC 19570, Pseudomonas aeruginosa ATCC 27853, Brucella melitensis Rev1 and field isolates of Vibrio anguillarum, Aeromonas hydrophila, Yersinia ruckeri, Pseudomonas aeruginosa, Lactococcus garvieae, and Brucella abortus). Also, the inhibition of biofilm was monitored by scanning electron microscopy. The lowest MIC values of BA and DOT were measured, by broth method using microdilution, from Pseudomonas aeruginosa ATCC 27853, and were 0.385 and 0.644 mg/ml, respectively. Staphylococcus aureus was the most resistant to both BA and DOT. Using the microplate method, we observed that the strongest positivities for biofilm production were presented by Pseudomonas aeruginosa ATCC 27853 and also a clinical isolate of Lactococcus garviea. Lower values in the MIC scores for both B compounds were tested by measuring the inhibitory effect on biofilm production. We found that all the bacterial strains inhibited biofilm formation with the exception of the Pseudomonas aeruginosa strains for BA only and an isolate of Lactococcus garviea for DOT only. Such effects by BA and DOT are worth discussing in order to find novel approaches for different functions in medicine and industry using the bacteria tested.

The effectiveness of anti-R. equi hyperimmune plasma against R. equi challenge in thoroughbred Arabian foals of mares vaccinated with R. equi vaccine.

This study aimed to determine the effectiveness of a pregnant mare immunization of a Rhodococcus equi (R. equi) vaccine candidate containing a water-based nanoparticle mineral oil adjuvanted (Montanide IMS 3012) inactive bacterin and virulence-associated protein A (VapA), as well as the administration of anti-R. equi hyperimmune (HI) plasma against R. equi challenge in the mares' foals. The efficacy of passive immunizations (colostral passive immunity by mare vaccination and artificial passive immunity by HI plasma administration) was evaluated based on clinical signs, complete blood count, blood gas analysis, serological response (ELISA), interleukin-4 (IL-4) and interferon gamma (IFN- γ ), total cell count of the bronchoalveolar lavage fluids (BALF) samples, reisolation rate of R. equi from BALF samples (CFU/mL), lung samples (CFU/gr), and lesion scores of the organs and tissue according to pathological findings after necropsy in the foals. The vaccination of pregnant mares and HI plasma administration in the foals reduced the severity of R. equi pneumonia and lesion scores of the organs and tissue by 3.54-fold compared to the control foals. This study thus indicates that immunization of pregnant mares with R. equi vaccine candidate and administration of HI plasma in mares' foals effectively protect foals against R. equi challenge.