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Veterinary World Sep 2023Infectious bovine keratoconjunctivitis (IBK) causes a significant economic loss to cattle industries in many countries, including Kazakhstan. Although is recognized as...
BACKGROUND AND AIM
Infectious bovine keratoconjunctivitis (IBK) causes a significant economic loss to cattle industries in many countries, including Kazakhstan. Although is recognized as an etiologic agent of IBK, other bacterial and viral agents have been suspected to play a role in the pathogenesis of this disease. This study aimed to evaluate samples collected from the eyes of IBK-affected cattle in Eastern Kazakhstan at different stages of IBK for the presence of , , , , and Bovine Herpes Virus Type 1 (BHV-1) and to characterize gene sequence diversity from positive samples.
MATERIALS AND METHODS
Individual ocular swabs (n = 168) were collected from cattle that had clinical signs of IBK during the summer of 2022 on farms in the Abay region of Kazakhstan. Eye lesion scores (1, 2, and 3) were assigned depending on the degree of ocular damage. Infectious bovine keratoconjunctivitis-associated organisms were detected using a multiplex real-time polymerase chain reaction assay. The gene was sequenced from positive samples.
RESULTS
and BHV-1 were not detected in any of the collected samples. was identified in the majority of samples overall, usually in mixed infection with spp. was detected in 76.2% of animals and predominated in animals with eye lesion scores 2 and 3. was detected only in association with and/or in animals with eye lesion scores 2 and 3. was found in 57.7% of animals and was always identified in association with another organism. Sequencing of the gene in 96 samples from positive samples identified five PilA groups. The majority belonged to PilA group A. However, three new PilA groups were identified and designated PilA groups N, O, and P.
CONCLUSION
The results indicate a high prevalence of and in eyes of cattle with IBK on livestock farms in Eastern Kazakhstan. Additional novel PilA groups were identified.
PubMed: 37859972
DOI: 10.14202/vetworld.2023.1833-1839 -
Microbial Pathogenesis May 2023Infectious bovine keratoconjunctivitis (IBK) is the most important eye disease in ruminants worldwide. Moraxella bovis and Moraxella bovoculi can form biofilm and are...
Infectious bovine keratoconjunctivitis (IBK) is the most important eye disease in ruminants worldwide. Moraxella bovis and Moraxella bovoculi can form biofilm and are frequently isolated from affected animals. Antimicrobials are used worldwide to treat clinical cases of IBK, although they have limited success in clearing the infection. Therefore, photodynamic therapy using porphyrins as photosensitizing molecules is an alternative method to eliminate microorganisms, including biofilms. We evaluated the antibacterial activity of a zinc(II) metalloporphyrin (ZnTMeP) against M. bovis and M. bovoculi biofilms since this compound can efficiently inactivate planktonic Moraxella spp. This study was carried out with two reference strains of Moraxella spp. (M. bovis: ATCC® 10900 and M. bovoculli: ATCC® BAA1259). The antibacterial activity of 4.0 μM of the ZnTMeP porphyrin was evaluated on forming and consolidate biofilms with three 30-min cycles of white-light exposure for three days. The ZnTMeP porphyrin reduced M. bovis and M. bovoculi biofilm formation. In addition, ZnTMeP partially destroyed consolidated M. bovoculi biofilms in the second white-light irradiation cycle, although the porphyrin had no effect against the consolidated biofilm of M. bovis. Despite the biofilm still not being completely inactivated, our findings are promising and encourage further experiments using the phototherapy protocol.
Topics: Cattle; Animals; Porphyrins; Keratoconjunctivitis, Infectious; Cattle Diseases; Moraxella; Anti-Bacterial Agents; Moraxellaceae Infections; Biofilms; Photochemotherapy
PubMed: 36948363
DOI: 10.1016/j.micpath.2023.106081 -
Journal of Infection in Developing... Sep 2015Infectious bovine keratoconjunctivitis (IBK) is an important ocular disease which affects cattle worldwide. To advance towards IBK effective prevention and treatment...
INTRODUCTION
Infectious bovine keratoconjunctivitis (IBK) is an important ocular disease which affects cattle worldwide. To advance towards IBK effective prevention and treatment strategies, it is important to define the distribution and genetic diversity of potential virulence factors present in M. bovis and M. bovoculi. The objective of this work was to identify and to analyze Moraxella spp. potential virulence factor genes in a collection of clinical isolates.
METHODOLOGY
The presence and diversity of virulence factors in a collection of Moraxella spp. strains isolated since 1983 to 2009 in Uruguay was analyzed by PCR using primers for partial amplification of tolC, omp79, plb, fur and mbxA. The selection criterion of these genes was based on the fact that they encode virulence factors which could be present and conserved within strains, an important issue for the development of vaccines.
RESULTS
Differences in PCR amplification were observed within tolC (84%), omp79 (80%), plb (76%) and fur (44%) in M. bovis strains, whereas mbxA was amplified in all M. bovis and M. bovoculi strains. Regarding genetic diversity, the tolC nucleotide sequences were the less diverse within all M. bovis and mbxA were the less diverse within all M. bovis and M. bovoculi strains.
CONCLUSIONS
PCR amplifications suggest the occurrence of differences between both Moraxella species, related to evaluated genes within Moraxella spp. strains and suggests that both species may have different pathogenic attributes. MbxA and the outer membrane protein TolC might be considered for future studies to develop new vaccines against IBK.
Topics: Animals; Cattle; Cattle Diseases; DNA, Bacterial; Genetic Variation; Keratoconjunctivitis, Infectious; Moraxella; Polymerase Chain Reaction; Uruguay; Virulence Factors
PubMed: 26409746
DOI: 10.3855/jidc.6222 -
The Veterinary Clinics of North... Jul 2021Infectious bovine keratoconjunctivitis (IBK) involves multiple factors and opportunistic pathogens, including members of the genus Moraxella, specifically M bovis. The... (Review)
Review
Infectious bovine keratoconjunctivitis (IBK) involves multiple factors and opportunistic pathogens, including members of the genus Moraxella, specifically M bovis. The causal role of M bovis is clear, where the presence of virulence factors that facilitate colonization (pili) and host cytotoxicity (RTX toxins) are well characterized, and IBK has been reproduced in many models. Experimental infection with M bovoculi has failed to reproduce IBK-typical lesions in cattle thus far. However, recent work using genomics and mass spectrometry have found genomic diversity and recombination within these species, making species differentiation complex and challenging the ability to assign IBK causality to these organisms.
Topics: Animals; Cattle; Cattle Diseases; Keratoconjunctivitis, Infectious; Moraxella; Moraxellaceae Infections
PubMed: 34049659
DOI: 10.1016/j.cvfa.2021.03.004 -
Animal : An International Journal of... Jun 2021Infectious bovine keratoconjunctivitis (IBK) is a common ocular disease in cattle that causes economic losses to producers and negatively impacts animal welfare. In a... (Review)
Review
Infectious bovine keratoconjunctivitis (IBK) is a common ocular disease in cattle that causes economic losses to producers and negatively impacts animal welfare. In a 2016 survey of cow-calf producers in California, IBK was identified as the disease for which antimicrobials are most frequently used. The presented scoping review examined the available literature for methods to prevent IBK and for alternatives to antimicrobials to treat the disease that can be applied in cow-calf operations. Online databases were searched for publications about IBK in cattle populations that were reported from 1950 to 2020. Citations were systematically evaluated in a multi-stage approach using commercial software and summarized in a scoping review format. For the studies included in the review, most research (n = 50) has focused on the development of vaccines for the prevention of IBK. Although the quality of publications has improved over time, there is a lack of consistent evidence for vaccine efficacy against IBK in post-2000 experimental and conventional vaccine trials. A systematic analysis of vaccine studies is warranted. A limited number (n = 6) of studies evaluated the prevention of IBK through fly control, where most have found efficacy of this control measure. Several treatment options (n = 5) that do not include the use of antimicrobials have been investigated but remain at the preliminary stage of testing. Differences in breed susceptibility has been demonstrated with breeds belonging to the Bos indicus subspecies less frequently affected compared to those belonging to the Bos taurus subspecies. Hereford cattle and those lacking pigmentation around the eyelid margin are more frequently affected than other breeds. At present, there are few evidence-based measures that producers can utilize to reduce the burden of IBK in their herds and more research into the efficacy of fly control measures, non-antimicrobial treatment options, the continued search for a viable vaccine, as well as identifying genetic markers associated with traits that confer resistance to the disease are needed.
Topics: Animals; Cattle; Cattle Diseases; Female; Keratoconjunctivitis; Moraxellaceae Infections; Phenotype
PubMed: 34062463
DOI: 10.1016/j.animal.2021.100245 -
Animal Health Research Reviews Jun 2016Infectious bovine keratoconjunctivitis (IBK) is a common and important disease of calves. Without effective vaccines, antibiotic therapy is often implemented to minimize... (Meta-Analysis)
Meta-Analysis Review
Infectious bovine keratoconjunctivitis (IBK) is a common and important disease of calves. Without effective vaccines, antibiotic therapy is often implemented to minimize the impact of IBK. This review updates a previously published systematic review regarding comparative efficacy for antibiotic treatments of IBK. Available years of Centre for Biosciences and Agriculture International and MEDLINE databases were searched, including non-English results. Also searched were the American Association of Bovine Practitioners and World Buiatrics Congress conference proceedings from 1996 to 2016, reviews since 2013, reference lists from relevant trials, and U.S. Food and Drug Administration New Animal Drug Application summaries. Eligible studies assessed antibiotic treatment of naturally-occurring IBK in calves randomly allocated to group at the individual level. Outcomes of interest were clinical score, healing time, unhealed ulcer risk, and ulcer surface area. A mixed-effects model comparing active drug with placebo was employed for all outcomes. Heterogeneity was assessed visually and using Cochran's Q-test. Thirteen trials assessing nine treatments were included. Compared with placebo, most antibiotic treatments were effective. There was evidence that the treatment effect differed by day of outcome measurement. Visually, the largest differences were observed 7-14 days post-treatment. These results indicate improved IBK healing with many antibiotics and suggest the need for randomized trials comparing different antibiotic treatments.
Topics: Animals; Anti-Bacterial Agents; Bias; Cattle; Cattle Diseases; Keratoconjunctivitis, Infectious; Moraxella bovis; Moraxellaceae Infections
PubMed: 27427193
DOI: 10.1017/S1466252316000050 -
Vaccines Jun 2022A randomized control trial was performed over a five-year period to assess the efficacy and antibody response induced by autogenous and commercial vaccine formulations...
A Five Year Randomized Controlled Trial to Assess the Efficacy and Antibody Responses to a Commercial and Autogenous Vaccine for the Prevention of Infectious Bovine Keratoconjunctivitis.
A randomized control trial was performed over a five-year period to assess the efficacy and antibody response induced by autogenous and commercial vaccine formulations against infectious bovine keratoconjunctivitis (IBK). Calves were randomly assigned each year to one of three arms: an autogenous vaccine treatment that included (), , and antigens, a commercial vaccine treatment, or a sham vaccine treatment that consisted only of adjuvant. A total of 1198 calves were enrolled in the study. Calves were administered the respective vaccines approximately 21 days apart, just prior to turnout on summer pastures. Treatment effects were analyzed for IBK incidence, retreatment incidence, 205-day adjusted weaning weights, and antibody response to the type IV pilus protein (pili) of as measured by a novel indirect enzyme-linked immunosorbent screening assay (ELISA). Calves vaccinated with the autogenous formulation experienced a decreased cumulative incidence of IBK over the entire study compared to those vaccinated with the commercial and sham formulations (24.5% vs. 30.06% vs. 30.3%, respectively, = 0.25), and had less IBK cases that required retreatment compared to the commercial and sham formulations (21.4% vs. 27.9% vs. 34.3%, respectively, = 0.15), but these differences were not significant. The autogenous formulation induced a significantly stronger antibody response than the commercial ( = 0.022) and sham formulations ( = 0.001), but antibody levels were not significantly correlated with IBK protection ( = 0.37).
PubMed: 35746524
DOI: 10.3390/vaccines10060916 -
World Journal of Microbiology &... May 2022Infectious bovine keratoconjunctivitis (IBK) is an ocular disease affecting bovine herds worldwide, and it causes significant economic loss. The etiologic agent of IBK...
Infectious bovine keratoconjunctivitis (IBK) is an ocular disease affecting bovine herds worldwide, and it causes significant economic loss. The etiologic agent of IBK is considered to be Moraxella bovis, but M. ovis and M. bovoculi are frequently recovered of animals presenting clinical signs of IBK. The therapeutic measures available for its control have limited efficacy. Antimicrobial photodynamic therapy (aPDT) using porphyrins as photosensitizing molecules is an alternative method that can be used to reduce microbial growth. We evaluated the antibacterial activity of aPDT using two water-soluble tetra-cationic porphyrins (HTMeP and ZnTMeP) against 22 clinical isolates and standard strains of Moraxella spp. in vitro and in an ex vivo model. For the in vitro assay, 4.0 µM of porphyrin was incubated with approximately 1.0 × 10 CFU/mL of each Moraxella sp. isolate and exposed to artificial light for 0, 2.5, 5, and 7.5 min. Next, 50 µL of this solution was plated and incubated for 24 h until CFU measurement. For the ex vivo assay, corneas excised from the eyeballs of slaughtered cattle were irrigated with Moraxella spp. culture, followed by the addition of zinc(II) porphyrin ZnTMeP (4.0 μM). The corneal samples were irradiated for 0, 7.5, and 30 min, followed by swab collection, plating, and CFU count. The results demonstrated the in vitro inactivation of the strains and clinical isolates of Moraxella spp. after 2.5 min of irradiation using ZnTMeP, reaching complete inactivation until 7.5 min. In the ex vivo experiment, the use of ZnTMeP resulted in the most significant reduction in bacterial concentration after 30 min of irradiation. These results encourage future in vivo experiments to investigate the role of metalloporphyrin ZnTMeP in the inactivation of Moraxella spp. isolates causing IBK.
Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Cattle; Cattle Diseases; Keratoconjunctivitis; Keratoconjunctivitis, Infectious; Moraxella; Moraxellaceae Infections; Photochemotherapy; Porphyrins; Sheep
PubMed: 35501420
DOI: 10.1007/s11274-022-03291-8 -
Journal of the American Veterinary... Aug 2017OBJECTIVE To assess the association between a commercially available vaccine against Moraxella bovis and cumulative incidence of infectious bovine keratoconjunctivitis... (Randomized Controlled Trial)
Randomized Controlled Trial
Randomized blinded controlled trial to assess the association between a commercial vaccine against Moraxella bovis and the cumulative incidence of infectious bovine keratoconjunctivitis in beef calves.
OBJECTIVE To assess the association between a commercially available vaccine against Moraxella bovis and cumulative incidence of infectious bovine keratoconjunctivitis (IBK) from processing to weaning (primary objective) and body weight at weaning (secondary objective). DESIGN Randomized blinded controlled trial. ANIMALS 214 calves (≥ 2 months of age) born in the spring of 2015 at an Iowa State University cow-calf research unit with no visible lesions or scars on either eye. PROCEDURES Calves were randomly allocated to receive SC administration of a single dose of a commercial vaccine against M bovis (112 enrolled and 110 analyzed) or saline (0.9% NaCl) solution (111 enrolled and 104 analyzed). Calves were monitored for signs of IBK from treatment to weaning, and body weight at weaning was recorded. People involved in calf enrollment and outcome assessment were blinded to treatment group assignment. Cumulative incidence of IBK and weaning weight were compared between vaccinated and unvaccinated calves; the effect measure was the risk ratio and mean difference, respectively. RESULTS IBK was detected in 65 (59.1%) vaccinated calves and 62 (59.6%) unvaccinated calves (unadjusted risk ratio, 0.99; 95% confidence interval, 0.79 to 1.24) during the study period. No significant difference in weaning weights was identified between vaccinated and unvaccinated calves (unadjusted effect size, 4.40 kg [9.68 lb]; 95% confidence interval, -3.46 to 12.25 kg [-7.61 to 26.95 lb]). CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the commercially available M bovis vaccine was not effective in reducing the cumulative incidence of IBK or increasing weaning weight in beef calves.
Topics: Animals; Bacterial Vaccines; Cattle; Cattle Diseases; Female; Incidence; Iowa; Keratoconjunctivitis, Infectious; Moraxella bovis; Moraxellaceae Infections
PubMed: 28703672
DOI: 10.2460/javma.251.3.345 -
Veterinary World Dec 2023Infectious bovine keratoconjunctivitis (IBK) is a prevalent ocular disease that affects livestock, leading to substantial economic losses due to reduced production and...
BACKGROUND AND AIM
Infectious bovine keratoconjunctivitis (IBK) is a prevalent ocular disease that affects livestock, leading to substantial economic losses due to reduced production and culling of infected animals. spp. is common bacterial pathogens that can cause keratoconjunctivitis in livestock. Therefore, rapid and accurate diagnosis is crucial for effective treatment and disease control. This study aimed to develop a multiplex real-time polymerase chain reaction (mRT-PCR) assay for the detection and differentiation of , , and .
MATERIALS AND METHODS
Three reference strains of as positive controls and 36 lacrimal swab samples collected from cattle were used to evaluate the developed mRT-PCR assay DNA extraction that was performed using the RIBO-sorb DNA/RNA extraction kit. Primers and probes were designed using the SpeciesPrimer pipeline. The annealing temperature, primer and probe concentrations, and sensitivity and specificity of the assay were optimized.
RESULTS
An mRT-PCR assay was developed to detect pathogens associated with IBK in cattle on the basis of optimized parameters. The specificity and sensitivity of this assay were confirmed using samples containing individual pathogens (O - , B - , and BO - ), combinations of two pathogens (O-B, B-BO, and O-BO), and when the DNA of all three pathogens was present in a single reaction (O-B-BO). The analytical sensitivity of mRT-PCR for detecting and DNA was 21 copies or 50 fg per reaction, whereas that for . was 210 copies or 500 fg per reaction. In addition, this assay has been tested on samples isolated from the affected eyes of cattle in the Akmola region of the Republic of Kazakhstan.
CONCLUSION
For the first time in the Republic of Kazakhstan, the proposed mRT-PCR assay for the simultaneous detection of three spp. pathogens has been developed. This assay exhibits the required specificity and high sensitivity for m RT-PCR, facilitating the timely implementation of effective measures for disease control and the prevention of economic losses. These losses are linked to a reduction in livestock breeding value, a reduction in meat and milk production, a reduction in the reproductive performance of heifers, resulting in fewer offspring, as well as costs related to the treatment of affected animals.
PubMed: 38328358
DOI: 10.14202/vetworld.2023.2526-2532