Artículos Científicos

URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/14635

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Protective effect of synbiotic supplementation against Salmonella Typhimurium infection in young broiler chickens
(MDPI, 2026-05-05) Rivera-Perez, Walter; Barquero-Calvo, Elías; Chaves Hernández, Aida; Salas Duran, Catalina
Salmonella infection in poultry remains a major concern due to its economic impact and public health risks. Synbiotics have emerged as a natural strategy to improve gut health and resistance to enteric pathogens. This study evaluated the immune response and early protective effects of a synbiotic in broiler chickens using a reduced in vivo model of Salmonella Typhimurium infection. A total of 44 broiler chickens were randomly assigned to four dietary reatments: control (CT), control plus synbiotic (CT + Syn), challenged (ST), and challenged plus synbiotic (ST + Syn). Birds were challenged at 7 days of age and uthanized at day 12 for sample collection. Synbiotic supplementation reduced bacterial colonization and adhesion in the ileum, as assessed by intestinal content solation and immunofluorescence analysis. Additionally, the synbiotics mitigated lesion severity in the intestine, liver, and heart, increased anti-inflammatory IL-10 expression, and reduced pro-inflammatory cytokines IL-1β and TNF-α. Ileal histomorphometry showed increased epithelial height in the ST + Syn birds, while intestinal permeability was not affected. Improved body weight was also observed compared to the challenged birds without supplementation. In conclusion, synbiotic supplementation provided early protection against S. Typhimurium infection by modulating immune responses, preserving intestinal morphology, and supporting weight gain in broiler chickens
Diagnostic Performance of Rose Bengal, Competitive ELISA, and Native Hapten (NH) Assays in S19 Mass-Vaccinated Cattle in an Endemic Brucellosis Environment
(Universidad Nacional, Costa Rica, 2026-03-26) Bonilla-Machado, Wilson; Aguilar-Chavarría, Andrés; Chacón-Díaz, Carlos; BARQUERO-CALVO, ELIAS; Chaves-Olarte, Esteban; Guzmán Verri, Caterina; Sandí-Muñoz, Alexis; Moriyon, Ignacio; Blasco, Jose-María; Moreno, Edgardo; Hernández-Mora, Gabriela
Vaccination with S19 is the best alternative to control bovine brucellosis, but depending on the immunization protocol, it may induce long-lasting antibodies interfering with diagnostic tests. Conjunctival vaccinated brucellosis-free heifers (Farm 1) produced antibodies detected in RBT and cELISA that disappeared <50 days after immunization. In contrast, heifers of Farm 1 subcutaneously vaccinated with S19 reduced dose produced antibodies detected in 10% of the bovines for up to one year. Sera of brucellosis-free vaccinated heifers did not immunoprecipitate native hapten polysaccharide (NH). In contrast, sera of Brucella-infected bovines readily immunoprecipitated NH. A Brucella abortus infected herd (Farm 2), previously vaccinated with RB51 and subjected to regular tests and slaughter until reaching negative serology, was mass vaccinated with S19 through either the conjunctival or subcutaneous routes with reduced and complete doses. Bovines of Farm 2 displayed sustained and increasing RBT and cELISA positive reactions for a protracted period, with ~5% bovines reacting against NH, indicating an anamnestic response upon contact with field Brucella. After an abortion and isolation of field B. abortus at day 225 in one cow of Farm 2, a significantly higher ratio of cELISA/RBT reactors was detected (2.5±1.6%) than in preceding days (0.9±0.2). Previous vaccination with RB51 did not modify the herd brucellosis situation or the serological results of S19-vaccinated bovines. We conclude that serial testing of RBT-positive animals with cELISA is not an adequate diagnostic strategy and that the NH immunoprecipitation test helps identify actively infected cows in herds submitted to mass vaccination with S19.
Trypanosomatids in Costa Rican Bats: First Molecular Evidence of the Leishmania (Viannia) guyanensis Complex and Evidence of a Broader Host Association for Trypanosoma minasense
(Springer, 2026-03-19) Rubí-Chacón, Randall; Urbina-Villalobos, Andrea; Sibaja-Morales, Karen Daniela; Zuniga-Moya, María José; Dolz, Gaby
Purpose Molecular data on wildlife trypanosomatids in Central America remain limited, constraining our understanding of host associations and sylvatic transmission cycles in the region. We characterized Leishmania and Trypanosoma infections in Costa Rican bats and assessed contemporary circulation of Trypanosoma minasense in howler monkeys within a comparative phylogenetic framework. Methods Whole blood from 98 bats across 11 Costa Rican localities (2013–2014) was screened by PCR for Leishmania kDNA (120 bp), ITS-1 (~ 330 bp), and Trypanosoma 18 S SSU rRNA (nested PCR) with species-level identification based on sequence-confirmed amplicons. ITS-1 and 18 S amplicons were Sanger-sequenced and assigned by BLAST. For context, 18 S sequences from howler monkeys (Alouatta palliata) sampled in Costa Rica (2011–2025), including 20 animals from 2025, were included in phylogenetic analyses. Results Leishmania kDNA was detected in 4/98 bats (4.1%), but only one (Sturnira parvidens) yielded ITS-1 and clustered within the Leishmania (Viannia) guyanensis complex. Trypanosoma DNA was detected in 9/98 bats (9.2%): T. cruzi (n = 3), T. minasense (n = 3), and undetermined Trypanosoma spp. (n = 3). In 2025, 17/20 howler monkeys were PCR-positive for T. minasense; two were successfully sequenced and clustered within the Costa Rican T. minasense clade alongside bat-derived sequences. Conclusion We report the first ITS-1- confirmed molecular evidence of the L. (V.) guyanensis complex in Costa Rican bats, supporting evidence of a broader host association and long-term local persistence of T. minasense across bats and primates.
Diversidad de culícidos y análisis molecular de arbovirus en larvas de Aedes spp. de Costa Rica
(UNED Research Journal, 2025) Flores-Núñez, Sonia; Beltré-Núñez, Edwin; Argüello-Vargas, Silvia; Jiménez-Rocha, Ana Eugenia; Dolz, Gaby
ABSTRACT. “Diversity of culicids and molecular analysis of arboviruses in Aedes spp. larvae from Costa Rica”. Introduction: Understanding mosquito diversity, monitoring new species, and recognizing the role of vertical transmission are crucial to effective vector-borne disease management. Objective: To estimate culicid diversity and detect dengue, chikungunya, and Zika viruses in Aedes spp. larvae across 19 districts in Costa Rica. Methods: From August through November 2021, we collected 5 036 mosquito larvae in 26 localities, identified them taxonomically, analyzed them for diversity indices, and used real-time Polymerase Chain Reaction to detect viral RNA in Aedes spp. larvae. Results: We identified eight species of Culicidae, with Aedes aegypti being the most abundant (63.3%), followed by Aedes albopictus (13.9%), which is reported for the first time for Punta Morales. None of the 97 larval pools tested positive for dengue, chikungunya, or Zika. Conclusion: The larval composition exhibited low ecological diversity and no viral infection, indicating limited vertical transmission during the study period, while underscoring the need for sustained entomological surveillance.
Parvovirosis in a margay (Leopardus wiedii)
(Brazilian Journal of Veterinary Pathology, 2025-08-25) Hidalgo Dittel, Juan Diego; Such Basiana, Roger; Bass, Laura G.; Dolz, Gaby; Solórzano Morales, Antony; Olivares, Roberto W. I.
Clinical History: Multiple tissue samples from various organs of a juvenile margay (Leopardus wiedii) were collected during necropsy. Before death, the animal exhibited severe weakness, vomiting, diarrhea, dehydration, abdominal discomfort, and marked leukopenia.
Seroprevalencia de Besnoitia besnoiti, Coxiella burnetii y Chlamydia abortus en hatos bovinos lecheros de la zona norte de Costa Rica
(Universidad Nacional, Costa Rica, 2025) Fallas Elizondo, Daisy Elena; Jiménez Rocha, Ana Eugenia; Romero Zúñiga, Juan José; Dolz, Gaby
Besnoitia besnoiti y los agentes zoonóticos Coxiella burnetii y Chlamydia abortus ocasionan enfermedad reproductiva en bovinos. En Costa Rica no se cuenta con reportes de prevalencia de B. besnoiti y C. burnetii. El objetivo de este estudio fue determinar la seroprevalencia y distribución de estos tres agentes en fincas de lechería especializada y de doble propósito de la zona Huetar Norte de Costa Rica. Se realizó un estudio transversal descriptivo. Fueron estudiados 600 animales de 40 fincas (15 por finca), ubicadas en los distritos de Aguas Zarcas (5), Ciudad Quesada (9), Fortuna (4), Monterrey (2), Muelle (3), Venecia (5) y Zarcero (12). El análisis serológico se realizó mediante los ensayos inmunoenzimáticos comerciales de la compañía ID.VET (Montpellier, Francia). La seroprevalencia determinada para B. besnoiti fue alta (27,3%). Animales seropositivos se encontraron en un 80% de las fincas y en todos los distritos analizados, menos en la Fortuna, con las mayores prevalencias en Aguas Zarcas (64%), Venecia (36,6 %) y Zarcero (33,3 %). La seroprevalencia de C. burnetii fue 16,8 %, los animales positivos se encontraron en un 70 % de las fincas y distribuidos en todos los distritos, en especial Zarcero (24,6 %), Ciudad Quesada (19,2 %) y Aguas Zarcas (17,7 %). Con respecto a C. abortus, se determinó una seroprevalencia de 1,3 %, los animales seropositivos se encontraron solamente en un 17,5 % de fincas en tres distritos: Aguas Zarcas (3,3 %), Monterrey (3,3 %) y Ciudad Quesada (2,9 %). Se recomienda alertar a los grupos productores veterinarios y autoridades, para que tomen las medidas de prevención y control necesarias, en particular para C. burnetii y C. abortus, por su potencial zoonótico y realizar investigaciones para confirmar la presencia de estos agentes mediante aislamiento o diagnóstico molecular.
First report of Paragonimus mexicanus infection in a domestic cat from Costa Rica
(British Veterinary Association, 2026-01-06) Achi-Castro, Laura; García, Ricardo; Zúñiga-Moya, María; Dolz, Gaby; Arguedas, Randall
Paragonimus is the only genus in the family Troglotrematidae. Dogs, cats and other mammals may become infected by consuming crabs or shrimp harbouring metacercariae. A 1.11-year-old cat was presented with chronic coughing episodes. Thoracic radiography and ultrasonography suggested diffuse pneumonia. Cytology from a pulmonary granuloma and faecal examination revealed numerous trematode eggs (50–100 µm) consistent with Paragonimus spp. Molecular analysis of faecal DNA confirmed 100% nucleotide identity with Paragonimus mexicanus metacercariae previously reported from freshwater crabs in Puntarenas, Costa Rica. Antiparasitic therapy combining praziquantel, pyrantel and mebendazole resolved clinical signs. This case highlights the importance of including paragonimiasis in the differential diagnosis of cats with chronic respiratory disease in Central America, where aquatic intermediate hosts and wild reservoirs are abundant, even in peri-urban settings.
Combining RNAScope and RCA reveals a novel epitheliotropic bovine xipapillomavirus in udder papillomas
(Elsevier, 2025-11-01) Alfaro-Mora, Ramsés; ZOBBA, Rosanna; Cacciotto, Carla; ANTUOFERMO, Elisabetta; Pietro Burrai, Giovanni; Polinas, Marta; Rodríguez Barahona, Julia; Anfossi, Antonio; Dolz, Gaby; Alberti, Alberto
The diversity of papillomaviruses (PVs) remains largely unexplored, with many viral types still unidentified among mammalian hosts. Data on PV presence is particularly scarce in several regions of the world, including Central America. In this study, we report the identification and characterization of a novel Xipapillomavirus detected in udder papillomas from two dairy cows in Costa Rica. A combination of histopathology, RNA in situ hybridization (RNAScope), rolling circle amplification (RCA), and sequencing confirmed the viral presence, enabling genetic characterization and assessment of its cellular tropism. Based on our findings, we propose classifying this novel PV as a new type within the Bovine papillomavirus species, designated BPV45. Results revealed that BPV45 is an epitheliotropic virus closely related to BPV12 and belongs to the species Xipapillomavirus 1. Further research is needed to confirm the viral tropism for bovine udder tissue and to evaluate the potential economic impact on milk production and lactation performance.
Health assessment of Golden-Mantled Howler Monkeys (Alouatta Palliata Palliata) in dry forest from the North Pacific Coast, Costa Rica
(American Association of Zoo Veterinarians, 2025-03-14) Nodolf, Shannon B.; Smith, Joseph A.; Volle, Kurt A.; Bernal-Valle, Sofía; Dolz, Gaby; Russell, Mariah
The golden-mantled howler monkey (Alouatta palliata palliata) represents an excellent sentinel species for use in One Health modeling because of its extensive natural range, regular contact with humans and domestic animals, and susceptibility to zoonotic diseases. The purpose of this research is to establish baseline health assessments for free ranging golden-mantled howler monkeys in Marino Las Baulas National Park, Costa Rica. In April 2013, seven free ranging golden-mantled howler monkeys were anesthetized for physical examinations and biological sample collection, including blood for hematology and blood gas analysis. All seven howler monkeys studied appeared in good overall health. On physical exams, 4/7 (57%) had some level of dental disease, most notably crown fractures. Fecal samples for endoparasite evaluation were collected from the seven anesthetized animals as well as an additional three animals that were anesthetized but remained in the trees out of reach for full physical exams. Feces were collected from the rectum or collected from the ground immediately after defecation. Fecal analysis showed 9/10 (90%) had one or more species of intestinal parasites, and one animal tested positive for Giardia spp. Hematologic values showed a mild monocytosis and eosinophilia compared to other Alouatta spp. Trypanosoma spp. were present in the blood smear of one animal. Additional vector-borne disease testing found one individual PCR positive to Plasmodium spp., and one individual PCR positive to Venezuelan equine encephalitis virus. Antibodies for West Nile virus were found in 5/7 (71%) of the animals; however, PCR testing for West Nile virus and dengue virus was negative for all samples. This represents the first published health assessments for howler monkeys in this region.
Serosurvey of Arboviruses in Free-Ranging Mantled Howler Monkeys (Alouatta palliata) in Costa Rica
(Wildlife Disease Association, 2025-02-03) Larsen, R Scott; Moresco, Anneke; Karabatsos, Nick; Dolz, Gaby; Glander, Kenneth E.
We investigated the prevalence of arthropod-borne viral diseases in a population of free-ranging mantled howler monkeys (Alouatta palliata) in Costa Rica in 1998. Blood samples were opportunistically collected from monkeys anesthetized for another study. Serology was performed on 64 individuals to assess exposure of this population to vesicular stomatitis virus, equine encephalitis viruses, Mayaro virus, St. Louis encephalitis virus, yellow fever virus, and dengue virus. The New Jersey serotype of vesicular stomatitis (VSV-NJ) was the only pathogen for which the population tested positive (44% [28/64]). This is the first report of antibodies against VSV-NJ in nonhuman primates in Costa Rica.
Identification of Paragonimus mexicanus and P. caliensis in freshwater crabs from Costa Rica: evidence of zoonotic lung fluke diversity in Central America
(PLOS Neglected Tropical Diseases, 2026-01-13) Wehrtmann, Ingo S.; Hernández-Chea, Roderico; Magalhães, Célio; Dolz, Gaby; Zuniga Moya, María José; Romero-Chaves, Raquel; Villalobos-Rojas, Fresia
Paragonimus spp. are foodborne trematodes with complex life cycles involving freshwater snails and decapod crustaceans. In Central America, Paragonimus mexicanus is a known zoonotic agent, whereas the public health significance of P. caliensis remains unclear. Between 2015 and 2016, we surveyed freshwater crabs across 51 sites in 15 river basins spanning three major climatic regions in Costa Rica. A total of 419 crabs (10 species) were examined for metacercariae; male crabs were identified morphologically, and infected females were identified to species by 16S rRNA and COI sequencing. Metacercariae were detected in six crab species, three of which represent new hosts of Paragonimus. The highest prevalence in male crabs occurred in Ptychophallus uncinatus (55.6%, 25/45). Molecular analyses confirmed the presence of two Paragonimus species in crabs: P. mexicanus and P. caliensis. A binomial GLM showed that males had higher odds of infection than females (p = 0.0059). Most infections occurred in areas along the Caribbean coast and in the Northern Region, which drains into Lake Nicaragua and Río San Juan. A binomial GLM revealed that the probability of Paragonimus infection varied significantly across climatic regions. Crabs from the Caribbean slope had the highest odds of infection, followed by the Northern Region. In contrast, crabs from the Pacific slope were significantly less likely to be infected. These patterns support the existence of geographic clusters of transmission within Costa Rica. We provide the first species-level, molecular confirmation of infected female crabs in Costa Rica and identify three freshwater crab species as newly recognized second intermediate hosts. These findings expand the known host range and distribution of Paragonimus in Costa Rica and highlight the need for public health education about the risks of consuming undercooked freshwater crabs.
Molecular detection of vector-borne and hemotropic pathogens in raccoons (Procyon lotor) from a tropical ecotourism area in Costa Rica
(Elsevier Ltd on behalf of Australian Society for Parasitology, 2026-01-03) Calderon-Bailey, Jennifer; Rojas-Sanchez, Ernesto; Mata-Masís, María; Jiménez-Soto, Mauricio; Solorzano-Morales, Antony; Zúñiga-Moya, María José; Varela-Amador, Javier; Vega-Benavides, Karen; Dolz, Gaby
Interactions between wildlife, domestic animals, and humans in ecotourism settings could facilitate the circulation of pathogens with zoonotic potential. Raccoons Procyon lotor), due to their synanthropic behavior and adaptability, may serve as hosts for several infectious agents at these interfaces. This study aimed to investigate the presence of vector-borne and hemotropic pathogens in free-ranging raccoons inhabiting Manuel Antonio National Park (MANP) and its surrounding communities, a major tourist destination in Costa Rica. Between 2021 and 2022, nineteen raccoons were captured using Tomahawk traps, anesthetized, clinically examined, and sampled for hematological and molecular analyses. DNA extracted from blood was screened using real-time and conventional PCR assays targeting Anaplasma spp., Ehrlichia spp., Rickettsia spp., Trypanosoma spp., Mycoplasma spp., and canine protoparvovirus 1 (CPPV-1). Of the individuals tested, 6/19 (31.6 %) were positive for Anaplasmataceae, 4/14 (28.6 %) for Mycoplasma spp., and 6/14 (42.9 %) for CPPV-1. One raccoon was confirmed to carry Mycoplasma haemocanis (99 % nucleotide identity with GenBank accession MN294708), representing the first molecular identification of this species in raccoons worldwide. Coinfections were detected in five animals. No raccoons tested positive for Rickettsia spp. or Trypanosoma spp. Hematological profiles were largely within reference ranges; however, mild leukogram variations and occasional hyperglobulinemia were observed, with no consistent infection-associated pattern. These findings provide molecular evidence of pathogen presence in raccoons from a high-tourism area and highlight their potential epidemiological relevance at the wildlife-human interface. The results underscore the need for sustained One Health surveillance to better assess pathogen transmission risks in tropical ecotourism settings.
Nutrition management, nitrogen efficiency, and income over feed cost on dairy farms in Costa Rica
(American Dairy Science Association, 1998) Baars, R. M. T.
Twenty-two dairy farms in two ecologically different zones were visited repeatedly during the dry and wet seasons of 1995 to evaluate nutrition and pasture management, N efficiency on the farm, and income over feed costs with the use of a management support program. Excessive amounts of concentrates were fed, and no differences in amounts were detected between seasons. Utilization of forage was consequently low and even negligible on some farms. The amount of crude protein in the diet was generally too high. The removal of N from the farms via milk and culling represented 27 and 31% of the total N input for the two regions, respectively. The income over feed costs per cow ($3.04 and $1.84/d, respectively) was considered reasonable despite the high amount of concentrates.
Mannose-resistant hemagglutination, enzyme-linked immunosorbent assay, and immune electron microscopy for detection of k99 fimbrial antigen in escherichia coli from calves
(American Society for Microbiology, 1989) Hernández, Francisco; Caballero, Magaly; Rivera, Patricia
Mannose-resistant hemagglutination (MRHA) was evaluated for identification of Escherichia coli with K99 fimbriae. The sensitivity and specificity of MRHA, relative to the enzyme-linked immunosorbent assay, were 21 and 79%v, respectively. Disagreement between the tests may have been due in part to separation of pili from the ceUls, with resultant enzyme-linked immunosorbent assay-positive, MRHA-negative tests. MRHA was not useful as the sole means for the identification of E. coli with K99 fimbriae.
Immunodiffusion test for serodiagnosing subcutaneous zygomycosis
(American Society for Microbiology, 1990-09) Kaufman, Leo; Mendoza, Leonel; Standard, Paul G.
Los antígenos de filtrado de cultivo de Basidiobolus ranarum y Conidiobolus coronatus se analizaron por inmunodifusión (ID) con antisueros homólogos de conejo. Se encontró que B. ranarum y C. coronatus tenían cinco antígenos específicos cada uno. Los resultados de las pruebas con antisueros heterólogos indicaron que todas las especies compartían al menos un antígeno. Se desarrollaron pruebas de ID que incorporan las bandas de precipitina específicas como referencias para la detección de basidiobolomicosis y conidiobolomicosis. Estas pruebas se realizaron con sueros de humanos y caballos con basidiobolomicosis y conidiobolomicosis comprobadas, así como con sueros de control de humanos y animales con y sin infecciones micóticas y oomicóticas heterólogas. Solo los sueros de casos de basidiobolomicosis y conidiobolomicosis produjeron líneas de identidad con los precipitados de referencia de B. ranarum y C. coronatus, respectivamente. Se encontró que las pruebas de ID eran completamente sensibles y específicas para determinar la etiología de la zigomicosis causada por estas dos especies. Además, resultaron útiles para supervisar la resolución de las infecciones.
Rapid detection of vesicular stomatitis virus New Jersey serotype in clinical samples by using polymerase chain reaction
(American Society for Microbiology, 1993) Rodriguez, Luis L.; Letchworth, Geoffrey J; Spiropoulou, Christina F.; Nichol, Stuart T.
El virus de la estomatitis vesicular del serotipo Nueva Jersey (VSV-NJ) causa enfermedad vesicular en bovinos, cerdos y caballos en todo el continente americano. La enfermedad vesicular es clínicamente indistinguible de la fiebre aftosa (FA). Por lo tanto, los brotes de enfermedad vesicular en zonas libres de FA deben diagnosticarse rápidamente mediante métodos de laboratorio y las granjas afectadas deben permanecer en cuarentena hasta que los resultados de laboratorio confirmen la ausencia de FA. El diagnóstico se realiza actualmente en laboratorios de alta contención (nivel 3 de bioseguridad) mediante fijación del complemento y aislamiento del virus en cultivo de tejidos. Describimos aquí un método alternativo para la detección del ARN del VSV-NJ en muestras clínicas. Este método incluye un procedimiento rápido de extracción de ARN con guanidina-fenol ácido, junto con una reacción en cadena de la polimerasa (PCR) en un solo tubo con transcriptasa inversa. Mediante esta prueba, pudimos detectar el mayor número de muestras positivas (53 de 58), seguidas de la detección del complemento (48 de 58) y el aislamiento en cultivo de tejidos (43 de 58). Los cebadores seleccionados para este ensayo amplifican una región de 642 nucleótidos del gen de la fosfoproteína de VSV-NJ, pero no de VSV-IN. La secuenciación del producto de PCR permite la tipificación genética de aislados virales y estudios epidemiológicos. Dado que no se requieren materiales infecciosos para realizar esta prueba y que cualquier virus infeccioso presente en muestras clínicas se destruye mediante el tratamiento con guanidina ácida-fenol, el diagnóstico puede realizarse con seguridad en laboratorios de diagnóstico convencionales.
Detection of bovine trichomoniasis with a specific dna Probe and PCR amplification system
(American Society for Microbiology, 1994) Ho, Michael S. Y.; Conrad, Patricia A.; Conrad, Phillip J.; Lefebvre, Rance B.; Perez, Enrique; Bondurante, Roberto H.
Trichomoniasis is a widespread, economically important venereal disease of cattle which causes infertility and abortion. Effective control of trichomoniasis has been impeded by the insensitivity of traditional diagnostic procedures, which require the isolation and cultivation of the parasite, 7Titrichomonasfoetus, from infected cattle. We developed a 0.85-kb T.foetus DNA probe by identifying conserved sequences in DNAs from T.foetus that were isolated from cattle in California, Idaho, Nevada, and Costa Rica. The probe hybridized specifically to DNAs of T. foetus isolates from different geographic areas but not to DNA preparations of Trichomonas vaginalis, bovine cells, or a variety of bacteria from cattle. The probe detected DNA from a minimum of i05 T. foetus organisms. To improve sensitivity, a partial sequence of the probe was used to identify oligonucleotide primers (TF1 and TF2) which could be used to amplify a 162-bp product from T. foetus DNAs by PCR. A chemiluminescent internal T. foetus sequence probe was hybridized to Southern blots of the amplification product. This system detected as few as one T. foetus organism in culture media or 10 parasites in samples containing bovine preputial smegma. Analysis of 52 clinical samples showed that 47 (90.4%) of the 52 samples were correctly identified, with no false-positive reactions. In comparison, the traditional cultivation method detected 44 (84.6%) of the 52 samples from T. foetus-infected and uninfected bulls. These results indicate that the PCR-based amplification system could be a useful alternative method for the diagnosis of bovine trichomoniasis.
Brucella abortus 16s rRNA and lipid a reveal a phylogenetic relationship with members of the Alpha-2 subdivision of the class proteobacteria
(American Society for Microbiology, 1990-07) Moreno, Edgardo; Stackebrandt, Erko; Dorsch, Matthias; Wolters, Jörn; Mayer, Hubert; Busch, Michael
On the basis of ribosomal 16S sequence comparison, Brucella abortus has been found to be a member of the alpha-2 subdivision of the class Proteobacteria (formerly named purple photosynthetic bacteria and their nonphototrophic relatives). Within the alpha-2 subgroup, brucellae are specifically related to rickettsiae, agrobacteria, and rhizobiae, organisms that also have the faculty or the obligation of living in close association to eucaryotic cells. The composition of Brucella lipid A suggests a close phylogenetical relationship with members of the alpha-2 group. The chemical analysis of the lipid A fraction revealed that Brucella species contain both glucosamine and diaminoglucose, thus suggesting the presence of a so-called mixed lipid A type. The serological analysis with polyclonal and monoclonal antibodies is in agreement with the existence of mixe lipid A type in B. abortus. The amide-linked fatty acid present as acyl-oxyacyl residues were 3-O-C(16:o)l2:0o 3-O-C(16:o)l3:0o 3O0 C(16:o)l4:O0 and 3-0-C(l8:O)l4:O. The only amide-linked unsubstituted fatty acid detected was 3-OH-C16:0O The ester-linked fatty acids are 3-OH-C16:0, 3-OH-C18:0, C16:0, C17:0, and C18:0. Significant amounts of the large-chain 27-OH-C28: were detected together with traces of 25-OH-C26:0 and 29-OH-C30:0. Comparison of the Brucella lipid composition with that of the other Proteobacteria also suggests a close phylogenetical relationship with members of the alpha-2 subdivision. The genealogical grouping of Brucella species with pericellular and intracellular plant and animal pathogens as well as with intracellular plant symbionts suggests a possible evolution of Brucella species from plant-arthropod-associated bacteria.
Human ascariasis, an evolutionary complex relationship between host and parasite
(Universidad Nacional, Costa Rica, 2022) Baldi, Mario; Baldi, Norberto
Ascariasis is a debilitating parasitic disease that has decimated the health of hundreds of thousands of human beings, especially in developing countries. The lack of adequate prophylaxis of the parasite associated with an increased risk of immunological disease is a challenge mainly in developed countries where the prevalence of this parasite is very low. The evolutionary relationship and mechanisms by which the parasite was able to colonize and establish itself in human hosts have not yet been unraveled. In addition, the host immune response mechanisms to eliminate or control the parasite are not fully understood. Understanding these immunological mechanisms (proximates) will allow establishing better medical treatments for diseases related to the positive effects of parasitosis, thus also avoiding the undesirable effects of the parasitosis itself.
Anatomical and radiographic study on the appendicular skeleton of the Tamandua mexicana
(Universidad Nacional, Costa Rica, 2022-01) Calvo Varela, Ariana; Hernández Valerio, Mauren; Villalobos Morales, Dominique; Fernández Mesén, Alison; Alpizar Moreno, Katherina; Salas Zamora, Dennis; Miranda Fernández, Daniel; Chaverri Esquivel, Laura; Passos Pequeno, Andréia
Tamandua mexicana species has an important role in the natural ecosystem as a pest controller, feeding on insects such as termites. One of the main anatomical adaptations that this species has undergone has been to its thoracic extremities. Having detailed knowledge regarding the osteology of the thoracic limbs of T. mexicana provides a strong base for its application in clinical-surgical practice. In addition to collaborating with the greater understanding of animal physiology and behavior. Because there was a lack of description about the appendicular skeleton anatomy of this species, the objective of this investigation was to describe the osteology and the radiographic anatomy of the appendicular skeleton of the T. mexicana. The bones used belonging to the appendicular skeleton of two specimens of T. mexicana were properly cleaned using standard boiling and maceration techniques. The morphometry of the bones was performed using a measuring tape, pachymeter, and radiographies. With this study, it was possible to identify and describe the anatomical peculiarities such as the presence of the double scapular spine that shapes the caudolateral fossa, and at the end of the humerus, the supratrochlear foramen, in addition to a markedly prominent medial epicondyle. In addition, a difference was observed between metacarpal bones and the phalanges of the third digit compared to the other ones, as it is significantly thicker. These findings reinforced the evidence that a certain degree of anatomical specialization is a result of an adaptation of this species to its environment and diet. The knowledge provided by research like this contributes to the improvement of surgical techniques and diagnostic approach in the species.

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