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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 -
EFSA Journal. European Food Safety... Dec 2021In this opinion, the antimicrobial resistant bacteria responsible for transmissible diseases that constitute a threat to the health of cattle have been assessed. The...
In this opinion, the antimicrobial resistant bacteria responsible for transmissible diseases that constitute a threat to the health of cattle have been assessed. The assessment has been performed following a methodology based on information collected by an extensive literature review and expert judgement. Details of the methodology used for this assessment are explained in a separate opinion. A global state of play on antimicrobial resistance in clinical isolates of (non-VTEC) and is provided. Among those bacteria, EFSA identified and with ≥ 66% certainty as being the most relevant antimicrobial resistant bacteria in cattle in the EU based on the available evidence. The animal health impact of these most relevant bacteria, as well as their eligibility for being listed and categorised within the animal health law framework will be assessed in separate scientific opinions.
PubMed: 34938371
DOI: 10.2903/j.efsa.2021.6955 -
Veterinary World May 2021Infectious bovine keratoconjunctivitis (IBK; conjunctivitis) is a widespread eye disease in cattle. In 1960, the Gram-negative bacillus was discovered as one of IBK's...
BACKGROUND AND AIM
Infectious bovine keratoconjunctivitis (IBK; conjunctivitis) is a widespread eye disease in cattle. In 1960, the Gram-negative bacillus was discovered as one of IBK's etiological causal agents. This study aimed to clarify the epidemiological (epizootic) situation of cattle moraxellosis in the Republic of Kazakhstan. The study also maps the quantitative and qualitative indicators of the epidemiological (epizootic) process to develop more effective antiepizootic measures.
MATERIALS AND METHODS
We clinically examined both imported and local cattle species based on existing epidemiological (epizootological) units of economic entities in Kazakhstan. Then, we selected biomaterials for laboratory tests to screen for moraxellosis.
RESULTS
We clarified the epizootic situation for moraxellosis of cattle in Kazakhstan using data from the Meat Union of Kazakhstan, veterinary reports from the Veterinary Control and Surveillance Committee of the Ministry of Agriculture, Kazakhstan, and our results, obtained during visits to farms in the various regions of the republic.
CONCLUSION
Based on the data of the conducted studies, we developed epizootic visualization maps with quantitative indicators of the cattle moraxellosis epizootic-transfer processes within various regions of Kazakhstan for 2019. The data obtained from studies of the properties of the isolated cultures compared with the characteristics of reference strains gave grounds to classify them as belonging to the genus.
PubMed: 34220144
DOI: 10.14202/vetworld.2021.1380-1388 -
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 -
The Veterinary Clinics of North... Jul 2021Pili and cytotoxins are important virulence factors and antigens for Moraxella spp. Local and systemic immunity may play a role in the body's response to infectious... (Review)
Review
Pili and cytotoxins are important virulence factors and antigens for Moraxella spp. Local and systemic immunity may play a role in the body's response to infectious bovine keratoconjunctivitis (IBK). No evidence exists that eliminating the carrier state for IBK is possible or beneficial. Evidence for efficacious transfer of passive immunity from dams to calves is conflicting. Autogenous vaccines and commercial vaccines for putative pathogens for IBK have not yet shown efficacy in blinded randomized field trials. Study design features, such as randomization, blinding, diagnostic criteria, and use of a placebo, reduce the risk of bias in vaccine studies for IBK.
Topics: Animals; Bacterial Vaccines; Cattle; Cattle Diseases; Keratoconjunctivitis, Infectious; Vaccination
PubMed: 34049664
DOI: 10.1016/j.cvfa.2021.03.009 -
The Veterinary Clinics of North... Jul 2021Environmental factors that contribute to the pathogenesis of infectious bovine keratoconjunctivitis (IBK) include face flies, ultraviolet (UV) radiation, and mechanical... (Review)
Review
Environmental factors that contribute to the pathogenesis of infectious bovine keratoconjunctivitis (IBK) include face flies, ultraviolet (UV) radiation, and mechanical irritation from plant awns or dust. Limited research has shown face fly control to be associated with lower incidence of IBK. UV radiation is known to cause corneal irritation and damage in mammalian species. The increased formation of corneal dark cells has been observed following UV radiation in exposed calves. Moraxella bovis preferentially binds to corneal dark cells where it can be found in pits, which may be formed due to bacterial contact. Little is known about the efficacy of management of pasture plants on the prevention of IBK.
Topics: Animal Husbandry; Animals; Cattle; Cattle Diseases; Diptera; Eye Foreign Bodies; Keratoconjunctivitis, Infectious; Ultraviolet Rays
PubMed: 34049661
DOI: 10.1016/j.cvfa.2021.03.006 -
The Veterinary Clinics of North... Jul 2021Infectious bovine keratoconjunctivitis (IBK) is a multifactorial disease complex caused by opportunistic pathogens, classically those members of the genus Moraxella.... (Review)
Review
Infectious bovine keratoconjunctivitis (IBK) is a multifactorial disease complex caused by opportunistic pathogens, classically those members of the genus Moraxella. However, IBK in some situations is associated with other potentially pathogenic agents, which include Mycoplasma bovoculi, Mycoplasma bovis, Ureaplasma diversum, bovine herpesviruses, and Chlamydia sp. Ocular infections that may resemble IBK are also caused by Listeria monocytogenes. These agents and their association with IBK are reviewed in this article.
Topics: Animals; Bacteria; Cattle; Cattle Diseases; Keratoconjunctivitis, Infectious; Moraxella; Virulence Factors
PubMed: 34049660
DOI: 10.1016/j.cvfa.2021.03.005 -
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 -
The Veterinary Clinics of North... Jul 2021Establishing causation, otherwise known as causal assessment, is a difficult task, made more difficult by the variety of causal assessment frameworks available to... (Review)
Review
Establishing causation, otherwise known as causal assessment, is a difficult task, made more difficult by the variety of causal assessment frameworks available to consider. In this article, Bradford Hill viewpoints are used to discuss the evidence base for Moraxella bovis and Moraxella bovoculi being component causes of infectious bovine keratoconjunctivitis. Each of the nine Bradford Hill viewpoints are introduced and explained: strength, consistency, specificity, temporality, biologic gradient, plausibility, coherence, experiment, and analogy. Examples of how the viewpoints have been applied for other causal relations are provided, and then the evidence base for M bovis and M bovoculi is discussed.
Topics: Animals; Cattle; Cattle Diseases; Keratoconjunctivitis, Infectious; Moraxella; Moraxella bovis; Moraxellaceae Infections
PubMed: 34049658
DOI: 10.1016/j.cvfa.2021.03.003 -
The Veterinary Clinics of North... Jul 2021Studies have sought to develop effective vaccines against infectious bovine keratoconjunctivitis (IBK). Most research has focused on parenterally administered vaccines... (Review)
Review
Studies have sought to develop effective vaccines against infectious bovine keratoconjunctivitis (IBK). Most research has focused on parenterally administered vaccines against Moraxella bovis antigens; however, researchers have also included Moraxella bovoculi antigens in vaccines to prevent IBK. Critical knowledge gaps remain as to which Moraxella spp antigens might be completely protective, and whether systemic, mucosal, or both types of immune responses are required for protection against IBK associated with Moraxella spp. Immune responses to commensal Moraxella spp residing in the upper respiratory tract and eye have not been analyzed to determine if these responses control colonization or contribute to IBK.
Topics: Animals; Bacterial Vaccines; Cattle; Cattle Diseases; Keratoconjunctivitis, Infectious; Moraxella; Moraxella bovis; Moraxellaceae Infections
PubMed: 34049657
DOI: 10.1016/j.cvfa.2021.03.002