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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 -
Scientific Reports Oct 2022Many proteins of the Repeats in Toxins (RTX) protein family are toxins of Gram-negative pathogens including hemolysin A (HlyA) of uropathogenic E. coli. RTX proteins are...
Many proteins of the Repeats in Toxins (RTX) protein family are toxins of Gram-negative pathogens including hemolysin A (HlyA) of uropathogenic E. coli. RTX proteins are secreted via Type I secretion systems (T1SS) and adopt their native conformation in the Ca-rich extracellular environment. Here we employed the E. coli HlyA T1SS as a heterologous surrogate system for the RTX toxin MbxA from the bovine pathogen Moraxella bovis. In E. coli the HlyA system successfully activates the heterologous MbxA substrate by acylation and secretes the precursor proMbxA and active MbxA allowing purification of both species in quantities sufficient for a variety of investigations. The activating E. coli acyltransferase HlyC recognizes the acylation sites in MbxA, but unexpectedly in a different acylation pattern as for its endogenous substrate HlyA. HlyC-activated MbxA shows host species-independent activity including a so-far unknown toxicity against human lymphocytes and epithelial cells. Using live-cell imaging, we show an immediate MbxA-mediated permeabilization and a rapidly developing blebbing of the plasma membrane in epithelial cells, which is associated with immediate cell death.
Topics: Humans; Acyltransferases; Bacterial Proteins; Escherichia coli; Escherichia coli Proteins; Hemolysin Proteins; Moraxella bovis; Type I Secretion Systems
PubMed: 36280777
DOI: 10.1038/s41598-022-22480-x -
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 -
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 -
Vaccine: X Dec 2023Infectious bovine keratoconjunctivitis (IBK; pinkeye) is generally considered to be caused by corneal infections with . Previous studies demonstrated that...
BACKGROUND
Infectious bovine keratoconjunctivitis (IBK; pinkeye) is generally considered to be caused by corneal infections with . Previous studies demonstrated that cytotoxin-specific mucosal immune responses in the bovine eye can be stimulated by intranasal vaccination with a recombinant cytotoxin subunit adjuvanted with polyacrylic acid.
METHODS
A randomized controlled field trial (two-arm parallel design with blinding) was conducted in beef steers in Northern California to determine if this vaccine could prevent naturally occurring IBK and/or reduce morbidity rates associated with this disease. Beef steers were vaccinated intranasally on days 0 and 21 with either a recombinant cytotoxin subunit adjuvanted with polyacrylic acid (Vaccine group) or adjuvant alone (Control group). Eye examinations were performed on all steers every 7 days for 16 weeks to document the occurrence of IBK and to determine sizes of corneal ulcers. Serum and tear samples were collected on days 0, 42, and 112 from a subset of animals to measure changes in systemic and ocular immune responses to cytotoxin.
RESULTS
The cumulative proportion of steers that developed IBK after 16 weeks did not differ between groups. Variables related to disease severity were numerically lower in steers that received the experimental vaccine. IBK-affected Vaccine group steers had a significantly lower number of observation weeks with severe ulcers versus Control group steers. Cytotoxin-specific tear IgA was significantly higher in Vaccine group compared to Control group steers on day 112. Although the proportion of animals that developed corneal ulcers associated with IBK did not differ between groups, the lowered metrics of disease severity in vaccinated steers suggests that intranasal vaccination with recombinant cytotoxin can reduce the severity of IBK in cattle.
PubMed: 37693844
DOI: 10.1016/j.jvacx.2023.100378 -
International Journal of Systematic and... Feb 2024A novel species of the genus was isolated from an ocular swab from a cow with infectious bovine keratoconjunctivitis. 16S rRNA gene sequencing suggested this species...
A novel species of the genus was isolated from an ocular swab from a cow with infectious bovine keratoconjunctivitis. 16S rRNA gene sequencing suggested this species was (99.59 % nucleotide identity). Average nucleotide identity was calculated using a draft whole genome sequence of this strain compared with type strains of closely related species and results established that it represents a new species. The genome size was 2 006 474 nucleotides and the G+C content was 42.51 mol%. The species could not be identified by matrix assisted laser desorption/ionization-time of flight mass spectrometry using a commercial database, confirming the novelty of the strain. We propose the name sp. nov. for this new species. The type strain is Tifton1 and has been deposited into the American Type Culture Collection (TSD-373) and the National Collection of Type Cultures (NCTC), UK Health Security Agency (NCTC 14942).
Topics: Cattle; Animals; Moraxella; RNA, Ribosomal, 16S; Keratoconjunctivitis, Infectious; Phylogeny; Cattle Diseases; DNA, Bacterial; Bacterial Typing Techniques; Base Composition; Sequence Analysis, DNA; Fatty Acids; Keratoconjunctivitis; Moraxellaceae Infections; Nucleotides
PubMed: 38415687
DOI: 10.1099/ijsem.0.006281 -
Journal of Veterinary Diagnostic... Jan 2024Infectious bovine keratoconjunctivitis (IBK) is associated with 2 species of and . A third novel spp., designated tentatively as , has been identified from the eyes of...
Infectious bovine keratoconjunctivitis (IBK) is associated with 2 species of and . A third novel spp., designated tentatively as , has been identified from the eyes of cattle with and without pinkeye. These 3 spp. can be found in various combinations within the same clinical sample, making speciation of this genus directly from a sample impossible with Sanger sequencing. Assessing diversity found in IBK- and non-IBK-affected cattle eyes, independent of culture, may provide additional information about IBK by avoiding the selectivity bias of culturing. We developed a targeted NGS panel to detect and speciate these 3 spp. directly from bovine ocular swabs. Our targeted panel amplifies bacterial essential genes and the 16S-23S ribosomal RNA intergenic spacer region (ITS) of the 3 spp. and speciates based on these sequences. Our panel was able to differentiate the 3 species directly from DNA extracted from 13 swabs (6 from healthy animals, 7 from animals with IBK), and every swab except one (clinically healthy eye) had the 3 spp. Targeted NGS with sequencing of spp. housekeeping genes appears to be a suitable method for speciation of directly from ocular swabs.
Topics: Cattle; Animals; Moraxella; Keratoconjunctivitis, Infectious; Mycoplasma Infections; Moraxellaceae Infections; Cattle Diseases; High-Throughput Nucleotide Sequencing
PubMed: 38018659
DOI: 10.1177/10406387231216698 -
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 -
Veterinary Microbiology Jul 2023Infectious bovine keratoconjunctivitis (IBK), commonly known as pinkeye, has a marked negative impact on the economy of the cattle industry. Moraxella species, including...
Infectious bovine keratoconjunctivitis (IBK), commonly known as pinkeye, has a marked negative impact on the economy of the cattle industry. Moraxella species, including Mor. bovis and Mor. bovoculi, which have been associated with this disease, colonize clinically healthy eyes as well, suggesting that there are intrinsic changes that may occur to the ocular microbiota or the involvement of additional unrecognized organisms that contribute to IBK. To evaluate this, 104 ocular swabs collected from eyes with IBK or clinically healthy eyes from 16 different cattle herds were subjected to 16 S rRNA gene PCR and next generation sequencing (NGS) analysis. Organisms detected were similar across the herds and there was no difference in the total number of bacterial groups detected among IBK cases and controls. However, the percentages of the different organisms detected varied between the two groups, including Moraxella spp., with more Moraxella spp. in eyes with IBK than controls. Further, using culture and whole genome NGS, a new species of Moraxella (suggested name Mor. oculobovii) was detected from the eyes of cattle from two farms. This strain is non-hemolytic on blood agar, is missing the RTX operon, and is likely a non-pathogenic strain of the bovine ocular microbiome. Alteration of the ocular microbiota composition may have a predisposing role, enhancing bacterial infection and the occurrence of clinical IBK. Future studies are required to evaluate if these changes are permanent or if there is a shift in the microbiome following recovery from the infection and how antibiotics might affect the microbiome.
Topics: Animals; Cattle; High-Throughput Nucleotide Sequencing; Keratoconjunctivitis, Infectious; Keratoconjunctivitis; Conjunctivitis, Bacterial; Moraxella; Mycoplasma Infections; Moraxellaceae Infections; Cattle Diseases
PubMed: 37104939
DOI: 10.1016/j.vetmic.2023.109752 -
Journal of Medical Entomology Nov 2023House flies (Musca domestica Linnaeus) are vectors of human and animal pathogens at livestock operations. Microbial communities in flies are acquired from, and correlate...
House flies (Musca domestica Linnaeus) are vectors of human and animal pathogens at livestock operations. Microbial communities in flies are acquired from, and correlate with, their local environment. However, variation among microbial communities carried by flies from farms in different geographical areas is not well understood. We characterized bacterial communities of female house flies collected from beef and dairy farms in Oklahoma, Kansas, and Nebraska using 16S rDNA amplicon sequencing and PCR. Bacterial community composition in house flies was affected by farm type and location. While the shared number of taxa between flies from beef or dairy farms was low, those taxa accounted >97% of the total bacterial community abundance. Bacterial species richness was 4% greater in flies collected from beef than in those collected from dairy farms and varied by farm type within states. Several potential pathogenic taxa were highly prevalent, comprising a core bacterial community in house flies from cattle farms. Prevalence of the pathogens Moraxella bovis and Moraxella bovoculi was greater in flies from beef farms relative to those collected on dairy cattle farms. House flies also carried bacteria with multiple tetracycline and florfenicol resistance genes. This study suggests that the house flies are significant reservoirs and disseminators of microbial threats to human and cattle health.
Topics: Humans; Cattle; Female; Animals; Diptera; Muscidae; Houseflies; Farms; Anti-Bacterial Agents; Prevalence; Bacteria; Drug Resistance, Microbial
PubMed: 37612042
DOI: 10.1093/jme/tjad112