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201.
Use of touch-down polymerase chain reaction to enhance the sensitivity of Mycobacterium bovis detection. 总被引:4,自引:0,他引:4
Martín J Zumárraga Virginia Meikle Amelia Bernardelli Alejandro Abdala Hector Tarabla María I Romano Angel Cataldi 《Journal of veterinary diagnostic investigation》2005,17(3):232-238
The confirmatory diagnosis of Mycobacterium bovis (M. bovis) in animal samples is carried out by culture in Stonebrink media. However, culture is very slow because of the extremely long duplication time of the bacillus and difficult because of the scarcity of bacilli in diagnostic samples. This study describes the development of a single-tube touch-down polymerase chain reaction (PCR) protocol for the detection of M. bovis using primers that target the IS6110 element. Spiked water and milk as well as routine diagnostic samples (milk and nasal swabs) from M. bovis-positive cattle were tested. This protocol allows the rapid and sensitive detection of M. bovis in bovine samples by enhancing the sensitivity of standard PCR amplification. 相似文献
202.
B Peris V García E Blas P Segura J Martínez J M Corpa 《Journal of veterinary diagnostic investigation》2005,17(3):256-258
Pneumatosis cystoides intestinalis (PCI) is an infrequent condition of animals characterized by the existence of numerous thin-walled, gas-filled cystic structures within the intestinal wall and adjacent lymph nodes. Microscopically, the cystic structures appear to be dilated lymphatics located in the lamina propria, submucosa, muscularis, subserosa, mesentery, and mesenteric lymph nodes. This report describes a case of pneumatosis cystoides intestinalis in a rabbit doe from an organic farm where 20 rabbit does were fed ad libitum with a natural diet consisting of whole barley, pea beans, alfalfa hay, and a pelleted vitamin-mineral blend. A combination of nutritional, bacterial, and other factors are hypothesized as possible predisposing factors in the development of PCI. 相似文献
203.
A Aguado-Martínez G Alvarez-García I Arnaiz-Seco E Innes L M Ortega-Mora 《Journal of veterinary diagnostic investigation》2005,17(5):442-450
Avidity serological tests (avidity enzyme-linked immunosorbent assay [ELISA] and avidity Western blot) were developed and used to differentiate between acute (primary infection, reinfection, and recrudescence) and chronic Neospora caninum infection in cattle. In addition, the pattern of immunoglobulin G (IgG) avidity maturation against different specific antigens of N. caninum tachyzoites was studied. Sequential serum samples were collected from cattle naturally and experimentally infected with N. caninum. Four groups of experimentally infected cattle were included in the study and were representative of primary infection, reinfection, chronic infection, and noninfection. Serum samples were also collected from naturally infected cattle classified into nonaborting and aborting cows on the basis of clinical findings and serological profiles, and a third group composed of seronegative cows that seroconverted during the course of the experiment. All samples were tested by avidity ELISA and avidity Western blot. The IgG avidity ELISA allowed the discrimination between primary and chronic infection because all experimentally primary-infection cows showed low avidity indexes at week 4 postinfection (p.i.) compared with the high avidity values found at week 20 postinfection. However, this test did not allow the discrimination of reinfection or recrudescence from chronic infection. Regarding IgG avidity Western blot results, no antigenic markers correlating with acute (primary infection, recrudescence, and reinfection) or chronic infection were recognized. However, the 17-kD immunodominant antigen was mostly responsible for high avidity values obtained by avidity ELISA because it was intensively recognized by high-avidity antibodies in all chronically infected animals after urea treatment. 相似文献
204.
Cecilia Mónica Galosi Viviana Cid de la Paz Leandro Carlos Fernández Javier Pablo Martinez María Isabel Craig María Barrandeguy María Elisa Etcheverrrigaray 《Journal of veterinary diagnostic investigation》2005,17(5):500-502
This study describes the isolation of equine herpesvirus-2 (EHV-2) from the lung of an aborted equine fetus in Argentina. The isolated virus was confirmed as EHV-2 by indirect immunofluorescence using a rabbit anti-EHV-2 polyclonal antiserum and by virus-neutralization test using an equine polyclonal antibody against EHV-2. Restriction endonuclease DNA fingerprinting with BamHI also confirmed the identity of the virus as EHV-2. Furthermore, viral nucleic acid was detected by polymerase chain reaction from the original lung sample and from the DNA obtained from cells infected with the virus isolate. This work constitutes the first reported isolation of EHV-2 from an aborted equine fetus. The presence of EHV-2 in the lung of the aborted fetus would indicate that this virus is capable of crossing the placental barrier. However, no cause-effect relationship was established between the EHV-2 isolate and the abortion. 相似文献
205.
Pablo Gómez-Ochoa Francisco Javier Miana-Mena María Jesús Mu?oz Encarna Cativiela Francisco Gómez 《Canadian journal of veterinary research》2005,69(4):309-312
The purpose of this study was to isolate and cultivate a subpopulation of pluripotent stem cells (PSCs) from the peripheral blood of rabbits, which are frequently used in veterinary research as an animal model. Pluripotent stem cells, as described in human beings, are fibroblast-like cells that exhibit a CD34 marker, specific from other hematopoietic stem cells. Commonly used human commercial media has been researched for culturing rabbit PSCs. These findings allow us to contemplate the direct application of this simple and standardized methodology in several areas of study, such as of the pharmacological effect of many drugs on hematopoietic cells, veterinary practice, and even the study of new strategies in cellular therapy for some human diseases. 相似文献
206.
Cinta Calvet Jorge Pinochet Amèlia Camprubí Victoria Estaún Rodrigo Rodríguez-Kábana 《European journal of plant pathology / European Foundation for Plant Pathology》2001,107(6):601-605
The survival of two species of plant parasitic nematodes: the root-lesion nematode Pratylenchus brachyurus, and the root-knot nematode Meloidogyne javanica, was evaluated in saturated atmospheres of 12 natural chemical compounds. The infectivity of two isolates of arbuscular mycorrhizal fungi: Glomus mosseae and Glomus intraradices, under identical experimental conditions, was also determined. All the compounds tested exerted a highly significant control against M. javanica and among them, benzaldehyde, salicilaldehyde, borneol, p-anisaldehyde and cinnamaldehyde caused a mortality rate above 50% over P. brachyurus. The infectivity of G. intraradices was inhibited by cinnamaldehyde, salicilaldehyde, thymol, carvacrol, p-anisaldehyde, and benzaldehyde, while only cinnamaldehyde and thymol significantly inhibited mycorrhizal colonization by G. mosseae. 相似文献
207.
Damage caused by nematodes is one of the limiting factors in crop production. Traditional nematode management is based on
the use of crop rotations, resistant cultivars, nematicides, or combinations of these methods. For a crop like peanut (Arachis hypogaea), cultivars resistant to root-knot nematodes are not available. There are soybean (Glycine max) cultivars resistant to some of the species of root-knot nematodes (Meloidogyne spp.); however, most fields have nematode infestations composed of mixtures of species. Research at Auburn has shown that
tropical crops can be used effectively in rotation to manage nematode problems. Rotations with American jointvetch (Aeschynomene americana), castor (Ricinus communis), hairy indigo (Indigofera hirsuta), partridge pea (Cassia fasciculata), sesame (Sesamum indicum), and velvetbean (Mucuna deeringiana) have resulted in good nematode control and increased yields of peanut and soybean. Some crops (castor, sesame) are considered
‘active’ in that they produce compounds that are nematicidal, whereas others (e.g. corn, sorghum) are simply non-host, that is, ‘passive’. 相似文献
208.
Jean-Marc Ducruet Hortensia Sixto Jos-María Garcia-Baudin 《Pest management science》1993,38(4):295-301
Chlorophyll fluorescence induction was used as a probe to detect herbicide detoxification in tolerant or susceptible wheat cultivars. Experimental conditions have been carefully examined for establishing detoxification kinetics of chlorotoluron and metribuzin, two photosystem-II-inhibiting herbicides. After a root treatment, leaves were cut, placed in glass tubes and maintained in the dark. The fluorescence induction rise was examined repeatedly and detoxification kinetics were established from these data for the same position on the individual leaves. The herbicide-dependent fluorescence rise decreased within hours in chlorotoluron-tolerant but not in susceptible Triticum aestivum cultivars. In contrast, no significant reversion could be detected after metribuzin application in both tolerant and susceptible cultivars of Triticum durum. Near the fluorescence-determined half-inhibition of photosystem II, linear detoxification kinetics were obtained in individual leaves, thus providing an accurate measurement of relative detoxification rates. 相似文献
209.
González Llamazares OR Gutiérrez Martín CB Alvarez Nistal D de la Puente Redondo VA Domínguez Rodríguez L Rodríguez Ferri EF 《Veterinary microbiology》1999,70(1-2):55-66
A field comparison of the interferon-gamma (IFN-gamma) assay and the single intradermal cervical tuberculin (SICT) test for the diagnosis of bovine tuberculosis was conducted. A total of 1136 cattle belonging to 85 herds placed in 'Castilla y León' (northwestern Spain) were chosen, and 21 of these herds were subjected to the diagnostic assays two or three times at intervals of at least 4 months. All the animals positive to any of the tests were slaughtered and tuberculosis was confirmed by culture isolation method (CIM) and further identification by means of PCR. Only 10.6% of cattle reacted with the bovine PPD in the SICT test, a percentage that increased to 12.8% in the IFN-gamma assay. The sensitivity of the IFN-gamma assay compared to CIM was shown to be higher (84.9%) than that of the SICT test (80.2%), but the combination of both tests offered the highest sensitivity (92.9%). The number of false positive reactors (those animals in which CIM was negative) was considerably higher for the IFN-gamma assay than for the SICT test and, conversely, the number of false negative animals (M. bovis isolation but negative immunological result) was higher for the skin test than for the interferon assay. In the herds tested twice, tuberculosis was eradicated after the second cycle of testing in 50%, and in 75% after the third cycle in herds tested three times. The combination of these two techniques instead of separately seems, therefore, to be useful in eradication programmes against bovine tuberculosis. 相似文献
210.
Viseras J Hueli LE Adroher FJ García-Fernández P 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1999,46(8):505-509
The role of the ixodid tick Hyalomma lusitanicum Koch 1844 as a vector of Mediterranean or tropical theileriosis (caused by the protozoan parasite Theileria annulata Dschunkowsky et Luhs 1904) in southern Spain was studied. Hyalomma lusitanicum was the most common tick, and the only species of the genus Hyalomma L., found on T. annulata-infected cattle from the theileriosis enzootic area studied (province of Cádiz, southern Spain). Likewise, we found that all sera of the cattle previously considered as suspected of theileriosis by clinical signs, tested for T. annulata antibodies, were positive and all blood samples of these suspected cattle examined had infected erythrocytes. Partially fed H. lusitanicum adults were collected in the field on T. annulata-infected cattle in this enzootic area and fed on an uninfected calf in an experimental farm free of theileriosis and ticks. At approximately 3 weeks post-tick feeding on the calf, this became positive for T. annulata antibodies and T. annulata merozoites were found in erythrocytes from blood smears. These results show the ability of H. lusitanicum to transmit the protozoan parasite T. annulata to susceptible cattle and indicate that H. lusitanicum is probably an important vector of T. annulata in the enzootic area surveyed. 相似文献