Background: Chlamydia abortus is the etiological agent of ovine enzootic abortion (OEA), a worldwide disease that significantly impacts to cattle, sheep, and goat production. This bacterium causes abortions during the last third of gestation and its zoonotic. The lack of prior symptoms before an abortive event complicates the clinical diagnosis of OEA and its differentiation from other infections, highlighting the need for an effective diagnostic tool. Some conventional diagnostic methods could be accurate, but in some cases require expensive equipment and highly trained personnel, limiting their field application. Under this context, the loop-mediated isothermal amplification (LAMP) emerges as an accessible and efficient alternative, capable of operating at a constant temperature and simplifying the interpretation of results visually through colorimetry. Objective: To validate a new LAMP assay using colorimetry for the visual detection of Chlamydia abortus in domestic ruminants. Method: Fifty-six DNA samples collected from ruminants with abortion history were used as biologic control of reference. LAMP specific primers were designed for the TARP gene of C. abortus. A colorimetric assay was validated for the LAMP test of C. abortus (crLAMP-Chla). The concordance (K), sensibility (Se) and specificity (Sp) parameters of crLAMP-Chla were calculated considering real time PCR as reference. Results: The crLAMP-Chla detected the pathogen from 15 minutes at 65 °C, even at low DNA concentrations. The K, Se and Sp values were 1, 100% and 100% (P=0.05) respectively. Conclusion: This methodology represents a significant advancement for the control of C. abortus in ruminants, providing an accessible and efficient diagnostic tool to improve public and animal health.

Background: Bovine trichomoniasis is a venereal disease caused by Tritrichomonas foetus (T. foetus) that significantly impairs the reproductive health of cattle. While bulls are asymptomatic carriers of this protozoan, cows infected with T. foetus exhibit embryonic deaths, abortions, reproductive tract infections or infertility. In México, the first report of T. foetus was made more than 60 years ago and, despite of the importance of trichomoniasis in cattle, efforts to control it through surveillance, diagnosis and adequate characterization have been scarce. Objective: To confirm the presence of T. foetus in animals from northwest México via molecular detection, sequencing, and phylogenetic analyses. Methods: Forty biological samples (smegma and mucopurulent vaginal secretion) were collected and analyzed by PCR technique to identify T. foetus using specific primers. Utilizing samples positive for T. foetus, sequencing and phylogenetic analyses were performed over the molecular structure of the generated amplicons to verify their homology and genetic relationships. Results: The PCR technique identified T. foetus in smegma and in clinical cases of metritis. Sequences obtained from PCR products revealed a 99.65% of similarity and a bootstrap of 99% with isolates of T. foetus reported in China, Spain, and USA. Based on the sequencing results, five new Mexican isolates of T. foetus were published in NCBI. Conclusion: This is the first report confirming the presence of T. foetus in México using sequencing and phylogenetic analyses from positive cattle samples. Our research effort represents the basis for developing alternative and accurate tests to diagnose T. foetus as part of the strategy to epidemiologically control bovine trichomoniasis in the country

The interaction between Pneumocystis jirovecii and systemic inflammation has emerged as a potential modulator of cardiovascular risk. This review describes the potential of β-glucans to contribute to atherogenic inflammation. A narrative review was developed on the PubMed/MEDLINE, Scopus, Web of Science and Google Scholar databases. The inflammatory pathways induced by β-glucans from P. jirovecii contrast with the immunometabolic effects of dietary β-glucans. The relevance of serum (1→3)-β-D-glucans as a marker of systemic exposure was also described, although it is not specific to P. jirovecii. P. jirovecii β-glucans activate Syk–CARD9–NFκB, MAPK and STAT3 signalling pathways. This signalling promotes proinflammatory monocyte/macrophage polarization and a systemic microenvironment of low-grade inflammation with proatherogenic potential. The serum persistence of (1→3)-β-D-glucan indicates prolonged exposure, even in the absence of overt clinical manifestations of colonization. Conversely, dietary β-glucans have been observed to elicit regulatory effects facilitated by microbiota and metabolism. In experimental setting, a causal link has been established between fungal β-glucans and atherosclerosis. P. jirovecii β-glucans act as immunological mediators capable of amplifying pulmonary and systemic inflammation, constituting a possible modulator of cardiovascular risk. Distinguishing between fungal and dietary β-glucans is imperative for comprehending emerging mechanisms of vascular inflammation.

Introduction: Rickettsia is an intracellular, Gram-negative, zoonotic bacterium that is transmitted by arthropods, such as ticks, fleas and lice. Rickettsioses have been reported in Mexico since the 1930s, with a higher prevalence in the northern states. Infections affect both dogs and humans in marginalized areas, with Rickettsia rickettsii being the most pathogenic species and associated with high mortality rates. Methodology: This study aimed to detect R. rickettsii in dogs from Ciudad Obregón, Sonora, using the ompA gene PCR. Between July and August 2024, 110 EDTA whole blood samples were collected: 95 from dogs with a presumptive clinical diagnosis of rickettsiosis, and 15 from stray dogs with active tick infestations. DNA extraction, PCR amplification and product purification were performed at the Veterinary Molecular Biology Laboratory of the Instituto Tecnológico de Sonora. Sanger sequencing, Snap Gene Viewer, and BLASTn against GenBank were used to confirm the identity of the sequences. Results: Sequencing of the ompA fragment confirmed 99–100% homology with R. rickettsii. One positive case (6.7%) was detected, corresponding to a stray dog from a disadvantaged area of the municipality of Cajeme, indicating the presence of the pathogen in a localized area. Conclusions: The detection of R. rickettsii in a stray dog in Ciudad Obregón confirms the presence of the pathogen in the area, highlighting the importance of free-roaming canines and environmental conditions in sustaining vectors. Early diagnosis and control of ectoparasites are critical to reducing zoonotic transmission, underlining the importance of continuous molecular surveillance in public health.

Listeria monocytogenes is often found in pork intestines and can contaminate pork production, posing a risk to consumers. This study aimed to characterize 16 L. monocytogenes isolates from fresh and packaged pork loin, identify their serotypes, and assess antibiotic resistance. To evaluate chitosan susceptibility as a potential strategy to control L. monocytogenes in the pork industry and to determine its effectiveness in a eukaryotic model to demonstrate pathogenicity. Among the 16 isolates examined, 2 were identified as 1/2a, 12 as 1/2b, 2 as 4b, and 2 could not be assigned a serotype. Variations were observed in their pathogenicity factors. Some isolates were lacking in some virulence factors. In the antibiotic assays, all isolates demonstrated resistance to at least three antibiotics, and one of them exhibited resistance to as many as ten antimicrobial agents. To propose an alternative in the food industry as a decontamination agent, a low-molecular-weight chitosan was evaluated. It was shown that chitosan inhibits the growth of L. monocytogenes in a concentration of 0.25% in 45 min, resulting in a viable alternative against this pathogen, but in this work, one isolate exhibited resistance to chitosan (isolate Lm 1.2). Regarding infection in eukaryotic models, all isolates had the capacity to infect chicken embryos, except for isolate 1.2, which exhibited attenuated pathogenicity. These findings highlight the potential public health risk L. monocytogenes poses in pork and the need for continued research to develop effective control strategies.

Listeria monocytogenes is often found in pork intestines and can contaminate pork production, posing a risk to consumers. This study aimed to characterize 16 L. monocytogenes isolates from fresh and packaged pork loin, identify their serotypes, and assess antibiotic resistance. To evaluate chitosan susceptibility as a potential strategy to control L. monocytogenes in the pork industry and to determine its effectiveness in a eukaryotic model to demonstrate pathogenicity. Sixteen isolates were evaluated, and two were determined as serotype 1/2a, twelve were 1/2b, and none were serotype 4b. Variations were observed in their pathogenicity factors. All isolates could infect chicken embryos except isolate 1.2, which displayed attenuated pathogenicity. The isolates also demonstrated strong biofilm-forming abilities. It was shown that chitosan inhibits the growth of L. monocytogenes, resulting in a viable alternative against this pathogen, but in this work, one isolate exhibited resistance to chitosan. L. monocytogenes strains present in pork meat represent a public health risk. This study characterized L. monocytogenes isolates from pork, revealing diverse serotypes (1/2a, 1/2b) and strong biofilm-forming abilities. While chitosan exhibited antimicrobial activity against most isolates, resistance was observed in one strain. These findings highlight the potential public health risk L. monocytogenes poses in pork and the need for continued research to develop effective control strategies.