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1.
J Dairy Sci ; 107(4): 2099-2110, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37949405

RESUMEN

Previously, we used secondary electrospray ionization-mass spectrometry (SESI-MS) to investigate the diurnal patterns and signal intensities of exhaled (EX) volatile fatty acids (VFA) of dairy cows. The current study aimed to validate the potential of an exhalomics approach for evaluating rumen fermentation. The experiment was conducted in a switchback design, with 3 periods of 9 d each, including 7 d for adaptation and 2 d for sampling. Four rumen-cannulated original Swiss Brown (Braunvieh) cows were randomly assigned to 1 of 2 diet sequences (ABA or BAB): (A) low starch (LS; 6.31% starch on a dry matter basis) and (B) high starch (HS; 16.2% starch on a dry matter basis). Feeding was once per day at 0830 h. Exhalome (with the GreenFeed System), and rumen samples were collected 8 times to represent every 3 h of a day, and EX-VFA and ruminal (RM)-VFA were analyzed using SESI-MS and HPLC, respectively. Furthermore, the VFA concentration in the gas phase (HR-VFA) was predicted based on RM-VFA and Henry's Law (HR) constants. No interactions were identified between the types of diets (HS vs. LS) and the measurement methods on daily average VFA profiles (RM vs. EX or HR vs. EX), suggesting a consistent performance among the methods. Additionally, when the 3-h interval VFA data from HS and LS diets were analyzed separately, no interactions were observed between methods and time of day, indicating that the relative daily pattern of VFA molar proportions was similar regardless of the VFA measurement method used. The results revealed that the levels of acetate sharply increased immediately after feeding, trailed by an increase in the acetate:propionate ratio and a steady increase for propionate (2 h after feeding the HS diet, 4 h for LS), and butyrate. This change was more pronounced for the HS diet than the LS diet. However, there was no overall diet effect on the VFA molar proportions, although the measurement methods affected the molar proportions. Furthermore, we observed a strong positive correlation between the levels of RM and EX acetate for both diets (HS: r = 0.84; LS: r = 0.85), RM and EX propionate (r = 0.74), and RM and EX acetate:propionate ratio (r = 0.80). Both EX-VFA and RM-VFA exhibited similar responses to feeding and dietary treatments, suggesting that EX-VFA could serve as a useful proxy for characterizing RM-VFA molar proportions to evaluate rumen fermentation. Similar relationships were observed between RM-VFA and HR-VFA. In conclusion, this study underscores the potential of exhalomics as a reliable approach for assessing rumen fermentation. Moving forward, research should further explore the depth of exhalomics in ruminant studies to provide a comprehensive insight into rumen fermentation metabolites, especially across diverse dietary conditions.


Asunto(s)
Lactancia , Leche , Femenino , Bovinos , Animales , Leche/química , Lactancia/fisiología , Propionatos/metabolismo , Fermentación , Rumen/metabolismo , Digestión/fisiología , Dieta/veterinaria , Ácidos Grasos Volátiles/metabolismo , Almidón/metabolismo , Acetatos/análisis , Alimentación Animal/análisis
2.
Prev Vet Med ; 218: 105995, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37625212

RESUMEN

Quantitative risk assessment was used to estimate the risk of introducing foot-and-mouth disease (FMD) through bone-in beef from Argentina (FMD-free with vaccination status) into other FMD-free countries. A stochastic model was built to characterize all the steps from primary production to bone-in beef export and introduction into an FMD-free country. The probability that bone-in beef from at least one animal infected with the FMD virus (FMDV) was exported during a year was 5.27 × 10-3 (95% CI <10-10 - 5.19 x 10-2) or in other words one case in 190 years. The risk of FMDV introduction was sensitive to the probability of an outbreak occurring in Argentina (r [Spearman´s rank correlation] = 0.99) and the number of herds affected during an outbreak (r = 0.10). Additionally, the probability that susceptible animals in the importing country came into contact with infective material (bones) and generated an outbreak was 6.16 × 10-4 (95% CI <10-10 - 6.20 ×10-3) or one FMD outbreak every 1623 years on average. Based on the quantitative risk assessment results, the probability of FMDV introduction into a FMD-free country where vaccination is not practiced from a FMD-free country where vaccination is practiced associated with bone-in beef trade from Argentina was negligible. The risk of an FMD outbreak caused by the potential introduction of the FMDV was associated with the existing conditions in the country. Thus, maintaining the FMD-free status with or without vaccination would not be relevant.


Asunto(s)
Enfermedades de los Bovinos , Virus de la Fiebre Aftosa , Fiebre Aftosa , Animales , Bovinos , Fiebre Aftosa/epidemiología , Fiebre Aftosa/prevención & control , Argentina/epidemiología , Medición de Riesgo , Vacunación/veterinaria , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/prevención & control
3.
Regen Eng Transl Med ; 4(2): 92-103, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30288396

RESUMEN

To examine how the chemotactic agent stromal cell-derived factor-1alpha (SDF-1α) modulates the unique cellular milieu within rotator cuff muscle following tendon injury, we developed an injectable, heparin-based microparticle platform to locally present SDF-1α within the supraspinatus muscle following severe rotator cuff injury. SDF-1α loaded, degradable, N-desulfated heparin-based microparticles were fabricated, injected into a rat model of severe rotator cuff injury, and were retained for up to 7 days at the site. The resultant inflammatory cell and mesenchymal stem cell populations were analyzed compared to uninjured contralateral controls and, after 7 days, the fold-change in anti-inflammatory, M2-like macrophages (CD11b+CD68+CD163+, 4.3X fold-change) and mesenchymal stem cells (CD29+CD44+CD90+, 3.0X, respectively) was significantly greater in muscles treated with SDF-1α loaded microparticles than unloaded microparticles or injury alone. Our results indicate that SDF-1α loaded microparticles may be a novel approach to shift the cellular composition within the supraspinatus muscle and create a more pro-regenerative milieu, which may provide a platform to improve muscle repair following rotator cuff injury in the future.

4.
Rev Sci Tech ; 34(3): 985-92, 977-84, 2015 Dec.
Artículo en Inglés, Español | MEDLINE | ID: mdl-27044166

RESUMEN

The organisation and structure of the official Veterinary Services (OVS) are designed to meet a specific aim--the health certification of animal health, welfare and food safety in the production and processing stage. Disease prevention and control calls for programmes and projects that, depending on the characteristics of each disease, may involve any branch of the OVS, from the laboratory to field activities. For the purpose of this work, the model used is that of a country that is 'free from foot and mouth disease with vaccination' in accordance with the conditions stipulated in Chapter 8.8. of the World Organisation for Animal Health Terrestrial Animal Health Code. These conditions state that, to maintain this health status, a programme of monitoring and continuous control of the relevant variables must be implemented. This is achieved by applying good practice and identifying the critical control points in all processes, using a checklist that simplifies the task. The system that is developed can also serve as a guide for internal or external programme audits.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Fiebre Aftosa/prevención & control , Análisis de Peligros y Puntos de Control Críticos/métodos , Animales , Comercio , Internacionalidad , Vigilancia de la Población , Transportes , Vacunación , Vacunas Virales/administración & dosificación , Vacunas Virales/inmunología
8.
Rev Sci Tech ; 26(3): 657-68, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18293614

RESUMEN

The bovine spongiform encephalopathy (BSE) crisis clearly demonstrated the need to keep animal transmissible spongiform encephalopathies (TSE) under control in order to protect animal and human health. Scrapie is the most widespread TSE of livestock in the world. For this reason, health authorities in different countries have elaborated plans that aim towards scrapie eradication. The unusual nature of the scrapie agent and the fragmented status of scientific knowledge about it, along with the limitations of currently available diagnostic tools, make it unlikely that the objective of eradication will be achieved in the near future. Scientific research is focused on acquiring the knowledge that will improve the efficiency of these efforts.


Asunto(s)
Encefalopatía Espongiforme Bovina/prevención & control , Scrapie/prevención & control , Animales , Bovinos , Encefalopatía Espongiforme Bovina/diagnóstico , Encefalopatía Espongiforme Bovina/epidemiología , Encefalopatía Espongiforme Bovina/transmisión , Predisposición Genética a la Enfermedad , Cabras , Investigación , Medición de Riesgo , Scrapie/diagnóstico , Scrapie/epidemiología , Scrapie/transmisión , Ovinos , Especificidad de la Especie , Zoonosis
9.
Rev Sci Tech ; 25(1): 163-72, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16796046

RESUMEN

Preventing the spread of disease through international movements is one of the key objectives of the World Organisation for Animal Health (OIE). One of the ways it seeks to achieve this is by publishing international standards and guidelines aimed at, inter alia, preventing the importation of pathogens that are dangerous for animals and humans and strengthening Veterinary Services so that they can improve their surveillance and response systems. The OIE works in close partnership with the Food and Agriculture Organization of the United Nations (FAO), and together the two organisations have developed a joint initiative - the Global Framework for the Progressive Control of Transboundary Animal Diseases (GF-TADs). Member Countries of these organisations could increase their capacity to manage the risks of disease occurrences, whether natural or deliberately introduced, if they would all strictly implement existing OIE international standards. Compliance with these standards greatly depends on the political willingness of national policy-makers and on a successful transfer of resources to developing countries in support of good governance and appropriate policy implementation. A United Nations Resolution obliging its Member Countries to implement OIE standards could prove invaluable in this respect.


Asunto(s)
Enfermedades de los Animales/prevención & control , Comercio/normas , Planificación en Desastres/organización & administración , Cooperación Internacional , Formulación de Políticas , Enfermedades de los Animales/epidemiología , Animales , Salud Global , Humanos , Política Pública , Naciones Unidas
11.
Rev Sci Tech ; 24(3): 1095-104, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16642778

RESUMEN

In order to carry out the translation into Spanish of the Manual of diagnostic tests and vaccines for terrestrial animals (mammals, birds and bees) ensuring full scientific and linguistic accuracy, its authors relied on coordination between three types of experts: linguistic, translational and veterinary. In this paper the planning, execution and quality control of such work, which was undertaken with the support and guarantee of the World Organisation for Animal Health (OIE), is reported. In the conclusions the authors describe what they view as necessary guidelines for the OIE to apply in the future regarding its linguistic policy. The working methodology reported in connection with the translation of the Terrestrial Manual into Spanish will be useful for the translation of the Terrestrial Manual or other texts into languages other than Spanish, whether or not they are among the official languages of the OIE.


Asunto(s)
Enfermedades de los Animales/diagnóstico , Técnicas de Laboratorio Clínico/normas , Pruebas Diagnósticas de Rutina/veterinaria , Lenguaje , Animales , Pruebas Diagnósticas de Rutina/normas , Guías como Asunto , Humanos , Control de Calidad
12.
Vet Ital ; 40(4): 676-81, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-20422611

RESUMEN

Preventing the spread of disease through international trade is one of the primary objectives of the Office International des Epizooties (OIE), the World Organisation for Animal Health. This is accomplished by establishing international standards that facilitate trade while minimising the risk of introducing diseases such as bluetongue (BT). The OIE standards for BT are contained in the Terrestrial animal health code (Code) and the Manual of diagnostic tests and vaccines for terrestrial animals (Manual). These standards include procedures for prompt reporting of BT outbreaks; requirements that should be met for a country or zone to be defined as free of bluetongue virus (BTV); recommendations for the safe importation of live animals, semen and embryos into a BTV-free country or zone; and the general provisions that countries should meet to reduce the risk of spread of BTV through trade. The Manual describes in detail the various tests for the diagnosis of BT. It provides a list of prescribed tests; these are the tests that are required by the Code for the testing of animals in connection with international trade. There are 24 serotypes of BTV and infected countries have the right to restrict imports from countries that have different types of BTV. However, this should only be done if a surveillance and monitoring programme has confirmed that the other types are not present. Zoning for an arbovirus is difficult to apply but zoning for vectors is practicable. Some countries have demonstrated that there is no evidence of infection in their country or parts of their country even though there has been unrestricted animal movement between endemic zones and free zones. This freedom is due to the absence of vectors in the free zone. Based on this observation, free countries and zones can be established if an appropriate surveillance and monitoring programme is in place to define their boundaries. Consequently, there have been extensive changes in the Code to allow the establishment of BTV-free countries and zones and seasonally free countries and zones to provide the basis for safe trade, while minimising the risk of the introduction of BTV.

13.
Vet Ital ; 40(3): 29-30, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-20429130
14.
Rev Sci Tech ; 22(1): 227-36, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12793781

RESUMEN

Bovine spongiform encephalopathy (BSE) is a neurodegenerative disease of cattle caused by prions that was first described in the United Kingdom (UK) in 1986. The BSE epizootic that commenced in the UK in the 1980s has since spread into other countries in Europe and Asia through exports of contaminated meat-and-bone meal or infected cattle. Over the past few years, other emerging or reemerging diseases have spread into previously free countries or regions through international trade. This negative effect of globalisation means that to implement successful preventive and strategic programmes to safeguard animal health, such programmes must, as a priority, take a regional approach. Global thinking, regional planning and local performance constitute the key factors for the successful control of animal diseases. In South America, initial preventive actions against BSE were adopted in 1989. Further measures adopted since then and based on new scientific and technical findings, have led to the demonstration that the region is free of BSE. These early preventive actions have reliably protected the region from importing BSE-infected material. An integral part of the project to determine the BSE status of South America was the training of personnel, the incorporation of technology and the provision of updated information through close relationships with international organisations and prominent international researcher workers. Regional activities aimed at harmonising BSE prevention programmes, producing objective and transparent data on the equivalence of regional BSE status and facilitating regional and international trade have recently been launched. Maintaining the BSE-free status of the region must be given high priority by the beef agro-industrial sectors.


Asunto(s)
Enfermedades Transmisibles Emergentes/veterinaria , Encefalopatía Espongiforme Bovina/prevención & control , Animales , Bovinos , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/prevención & control , Encefalopatía Espongiforme Bovina/epidemiología , Salud Global , Humanos , Medición de Riesgo , Factores de Riesgo , América del Sur/epidemiología
15.
Artículo en Inglés | MEDLINE | ID: mdl-11765807

RESUMEN

Group A rotavirus (RV) and coronavirus (CV) are common viral pathogens associated with neonatal diarrhoea in numerous animal species. The purpose of this work was to investigate the presence of these viral agents in two farm populations of captured guanacos (Lama guanicoe) in the Argentinean Patagonia region, that developed severe diarrhoea outbreaks. Stool and serum samples were analysed for RV and bovine CV antigen and antibody enzyme-linked immunosorbent assay. Rotavirus was detected in faeces from two new-born guanacos with acute diarrhoea, one in each farm. After electrophoretic analysis, each isolated strain, showed a distinctive long dsRNA electropherotype characteristic of group A rotaviruses (4:2:3:2). In addition, 95% (38 of 40) of the sampled animals were positive for RV antibodies, suggesting a high prevalence of RV infection in the populations tested. No evidence of CV circulation by antigen or antibody analysis was observed. To our knowledge, this is the first report of the detection and isolation of RV associated with neonatal diarrhoea in Lama guanicoe.


Asunto(s)
Camélidos del Nuevo Mundo , Diarrea/veterinaria , Infecciones por Rotavirus/veterinaria , Rotavirus/aislamiento & purificación , Animales , Animales Recién Nacidos , Anticuerpos Antivirales/sangre , Argentina/epidemiología , Diarrea/epidemiología , Diarrea/virología , Heces/virología , Rotavirus/inmunología , Rotavirus/ultraestructura , Infecciones por Rotavirus/epidemiología
16.
Rev Argent Microbiol ; 32(1): 27-32, 2000.
Artículo en Español | MEDLINE | ID: mdl-10785940

RESUMEN

Fetal bovine serum (FBS) used in cell culture may be contaminated with viruses, among them bovine viral diarrhea virus (BVDV) affecting the production of biological reagents and the results of diagnosis. The filtration process used in the preparation of commercial FBS abrogates most viral agents that may be present in raw FBS, but BVDV may pass through the filters because of its small size and its pleomorphism. While detection of bovine herpes virus-1 and parainfluenza-3 (PI-3) is determined by observation of the cytopathic effect, and also by hemadsorption in the case of PI-3, the most frequently isolated BVDV is non cytopathic, and infects cells without morphological alterations, inducing problems that arise after several cell generations. Batches of raw and processed FBS were analyzed. Frequencies of BVDV detection in raw serum in Argentina were similar to those published for USA. By conventional methods for BVDV detection, only 2 of 20 commercial batches of FBS had BVDV. Using cell cultures maintained with high concentrations of the serum under study for at least 2 weeks, with detection of viral antigen by indirect immunofluorescence, the percentage of BVDV detection was 80%. This method shows that most lots of commercial FBS contain BVDV. RT-PCR allows faster detection of the viral genome, but it must be validated, as it does not show viral replication. To eliminate the problem of BVDV contamination in FBS, only gamma irradiated FBS is used in our laboratory.


Asunto(s)
Sangre/virología , Virus de la Diarrea Viral Bovina/aislamiento & purificación , Animales , Bovinos , Medios de Cultivo
17.
Rev. argent. microbiol ; 32(1): 27-32, ene.-mar. 2000.
Artículo en Español | LILACS | ID: lil-332541

RESUMEN

Fetal bovine serum (FBS) used in cell culture may be contaminated with viruses, among them bovine viral diarrhea virus (BVDV) affecting the production of biological reagents and the results of diagnosis. The filtration process used in the preparation of commercial FBS abrogates most viral agents that may be present in raw FBS, but BVDV may pass through the filters because of its small size and its pleomorphism. While detection of bovine herpes virus-1 and parainfluenza-3 (PI-3) is determined by observation of the cytopathic effect, and also by hemadsorption in the case of PI-3, the most frequently isolated BVDV is non cytopathic, and infects cells without morphological alterations, inducing problems that arise after several cell generations. Batches of raw and processed FBS were analyzed. Frequencies of BVDV detection in raw serum in Argentina were similar to those published for USA. By conventional methods for BVDV detection, only 2 of 20 commercial batches of FBS had BVDV. Using cell cultures maintained with high concentrations of the serum under study for at least 2 weeks, with detection of viral antigen by indirect immunofluorescence, the percentage of BVDV detection was 80. This method shows that most lots of commercial FBS contain BVDV. RT-PCR allows faster detection of the viral genome, but it must be validated, as it does not show viral replication. To eliminate the problem of BVDV contamination in FBS, only gamma irradiated FBS is used in our laboratory.


Asunto(s)
Animales , Bovinos , Sangre , Virus de la Diarrea Viral Bovina/aislamiento & purificación , Medios de Cultivo
18.
Zentralbl Veterinarmed B ; 46(3): 157-61, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10337237

RESUMEN

This study analysed sera from 390 llamas (Lama glama) from nine farms located in three different Argentine provinces: Buenos Aires, Cordoba and Jujuy. The samples were tested for antibodies against 8 virus known to infect cattle: bovine herpesvirus type 1 (BHV-1), bovine viral diarrhea virus (BVDV), bovine adenovirus (BAdV III), bovine enterovirus (BEV), bovine rotavirus (BRV), bluetongue virus (BTV), bovine leukaemia virus (BLV), and foot-and-mouth virus (FMDV) by conventional methods such as seroneutralization, immunoperoxidase staining, and agar gel immunodiffusion. The antibody prevalences detected in llamas were: BHV-1 in 0.77% (3/390), BVDV in 2.05% (8/390), BAdV III in 5.13% (20/390), BEV in 4.10% (16/390), BRV in 87.69% (342/390). No antibodies against BTV, BLV and VIAA (FMDV infection associated antigen) were detected.


Asunto(s)
Anticuerpos Antivirales/sangre , Camélidos del Nuevo Mundo/inmunología , Virosis/veterinaria , Animales , Argentina , Camélidos del Nuevo Mundo/sangre , Bovinos , Enfermedades de los Bovinos/virología , Línea Celular , Pruebas Serológicas , Virosis/diagnóstico , Virosis/inmunología , Virus/crecimiento & desarrollo , Virus/inmunología , Virus/aislamiento & purificación
19.
Rev Sci Tech ; 18(1): 104-21, 1999 Apr.
Artículo en Español | MEDLINE | ID: mdl-10190208

RESUMEN

The authors review the policies designed to prevent and deal with animal health emergencies which have been implemented in countries of South America. They describe the evolution of the epidemiological situation of the continent, the new arrangements for international trade in animals and products of animal origin arising from the creation of the World Trade Organization (WTO), and the consequences of such developments for livestock production in South America. Veterinary systems used to prevent and deal with emergencies in the eleven OIE Member Countries on the continent are described, together with emerging problems which confront the Veterinary Services of the continent, namely: exotic diseases, abnormal occurrence of endemic diseases subject to control programmes, faults in food-safety mechanisms, diseases which have an environmental impact, and problems connected with animal welfare. The emergencies which present the greatest risk to South America are foot and mouth diseases, transmissible spongiform encephalopathies, the porcine reproductive and respiratory syndrome, food poisoning, Newcastle disease and fowl plague. Other problems are the appearance of new strains of existing agents, and the presence of resistant individuals among species of bacteria or harmful arthropods. The authors emphasise the need to co-ordinate the prevention of emergencies with development work at the international level, particularly regional and international agreements, harmonization of procedures, progress in animal health and public health, risk analysis, etc. These systems and methods of prevention have a contribution to make in enhancing the potential of animal production in South America, and the adoption of stricter health and quality standards, according to criteria established by the WTO Agreement on the Application of Sanitary and Phytosanitary Measures.


Asunto(s)
Enfermedades de los Animales/prevención & control , Animales Domésticos , Brotes de Enfermedades/veterinaria , Enfermedades de los Animales/epidemiología , Animales , Brotes de Enfermedades/prevención & control , Urgencias Médicas/veterinaria , América del Sur/epidemiología
20.
Prev Vet Med ; 33(1-4): 283-96, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9500182

RESUMEN

The development of a liquid-phase blocking sandwich ELISA (LPBE) to measure antibodies (Ab) produced in cattle with the O, A and C foot-and-mouth disease virus (FMDV) types of commercial vaccines used in Argentina is described. The test was specific: 99% of naïve cattle sera (n = 130) gave titres below log10 = 1.2, and none had a titre above log10 = 1.5. Comparative studies with serum neutralization test (SNT) using sera from cattle which received one or more vaccine doses is reported. The overall rank correlation coefficient (Spearman's rho, rs) between SNT and LPBE were highly significant (rs > 0.67, P < 0.0001) for all vaccine strains. LBPE Ab titres on sera collected 90 days post vaccination were compared with results of cattle protection tests by applying a logistic regression. The minimum Ab titres at which 85% and 75% of the cattle were protected for each FMDV type were determined in order to interpret field Ab data in terms of protection. Application of this method allows large scale serological examinations to monitor antibody levels in vaccinated animals as an indirect indicator of the FMD control program status in the field. Its use in the evaluation of commercial batches of FMD vaccine is discussed.


Asunto(s)
Anticuerpos Antivirales/sangre , Aphthovirus/inmunología , Enfermedades de los Bovinos/prevención & control , Fiebre Aftosa/prevención & control , Vacunas Virales/inmunología , Animales , Argentina/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/inmunología , Brotes de Enfermedades/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Fiebre Aftosa/epidemiología , Fiebre Aftosa/inmunología , Modelos Logísticos , Pruebas de Neutralización/veterinaria , Conejos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Vacunación/veterinaria
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