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41.
In order to describe the normal bacterial flora in vaginas of Criollo Limonero cows, 51 healthy multiparous cows, at least
90-day postpartum, were selected. Duplicated swabs (N = 102) were taken from the vaginal fornix of cows to perform aerobic and anaerobic cultures as well as conventional biochemical
tests. Out of 102 swabs, bacterial growth was obtained in 55 (53.9%) while the remaining 47 (46.1%) did not exhibited any
bacterial growth. Of the 55 bacterial growths, 23 (41.8%) were aerobic whereas 32 (58.1%) were anaerobic. Likewise, 29 (52.72%)
of bacterial growths were pure and 26 (47.27%) were mixed. Under both aerobic and anaerobic conditions, Gram positive bacteria
were predominant (81.82% and 73.08%, respectively) over Gram negative bacteria (18.18% and 26.92%, respectively). Isolated
bacteria were Arcanobacterium pyogenes (22.92%), Staphylococcus aureus (15.63%), Staphylococcus coagulase negative (17.71%), Erysipelothrix rhusiopathiae (6.25%), Bacteroides spp. (13.54%), and Peptostreptococcus spp. (7.29%). In conclusion, normal vaginal bacterial flora of Criollo Limonero cows was predominantly Gram positive and included
A. pyogenes, S. aureus, coagulase negative Staphylococcus, E. rhusiopathiae, Bacteroides spp., and Peptostreptococcus spp. In Criollo Limonero cattle, adaptive aspects such as development of humoral and physical mechanisms for defense, and bacterial
adaptation to host deserve research attention. 相似文献
42.
Pablo Sebastián Reineri María Sumampa Coria Santiago Callejas Gustavo Adolfo Palma 《Anatomia, histologia, embryologia》2020,49(6):820-829
The objectives of the present study were (experiment 1) to characterized development and dynamics of the dominant follicles (DF) and the corpus luteum (CL) to determine patterns of two (W2) and three (W3) follicular waves in beef heifers, and (experiment 2) to determine gene expression of growth factors gene expression in follicular cells of W2 and W3 heifer. Twenty-eight Braford heifers were used. Dominant follicular and CL were monitored daily by ultrasonography to identify the development W2 and W3 in heifers. Pre-ovulatory DF were aspirated on day 19 in W2 and on day 22 in W3 heifers. In W2 and W3, follicular cells (FC) of gene expression of growth differentiation factor 9, bone morphogenetic protein 15 (BMP15), fibroblast growth factor basic, transforming growth factor beta receptor 1, bone morphogenetic protein receptor type IB and fibroblast growth factor receptor 2 were evaluated. The regression of the DF of the first follicular wave and the emergency of the DF of the second follicular wave began later in the heifers W2 than in W3 (p = .02 and p < .01). The regression of the CL began earlier in the W2 than in W3 group (p < .01). Gene expression of growth factors and receptors was similar between groups. However, higher relative levels of BMP15 was observed in W2 group (p = .07). Results propose that wave patterns were regulated by the development time of the DF in the first wave and the life of the CL. Furthermore, higher levels of BMP15 could produce shorter life of CL. The present work suggest that ultrasonography associated with molecular assays could be used as an easy and effective tool to characterize follicular wave patterns. 相似文献
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46.
In vitro inhibition of Citrobacter freundii, a red-leg syndrome associated pathogen in raniculture, by indigenous Lactococcus lactis CRL 1584 总被引:2,自引:0,他引:2
Pasteris SE Guidoli MG Otero MC Bühler MI Nader-Macías ME 《Veterinary microbiology》2011,151(3-4):336-344
Red-leg syndrome (RLS) is one of the main infectious diseases that cause economic losses in Lithobates catesbeianus hatcheries, Citrobacter freundii being an etiological agent. Treatment or prevention with therapeutics or chemicals results in modifications of the indigenous microbiota, development of antibiotic resistance, presence of their residues in food and enhancement of production costs. Thus, probiotics could be used as an alternative therapy. Lactic acid bacteria are part of the indigenous microbiota of healthy frogs and can prevent pathogen colonization by different mechanisms, including the production of antagonistic substances. In this work, the evaluation and characterization of the inhibition of C. freundii CFb by Lactococcus lactis subsp. lactis CRL 1584, a potentially probiotic candidate, were carried out. This strain produced lactic acid, H(2)O(2) and bacteriocin in static and shaken conditions and inhibited pathogen growth in associative cultures, with an earlier inhibition under agitated conditions. The elimination of each of the antimicrobial metabolites partially abolished the inhibition of the pathogen, suggesting that the inhibitory effect could be attributed to a combined action of the three antagonistic molecules. Electron microphotographs revealed the damage caused by L. lactis CRL 1584 supernatants to C. freundii cells. The addition of pure lactic acid, H(2)O(2) and bacteriocin to the culture media showed that each metabolite caused different morphological modifications in C. freundii, in agreement with the effect on viable cell counts. The results support the possibility that L. lactis CRL 1584 might be considered as a probiotic to be used in the prevention of RLS in raniculture. 相似文献
47.
Aleutian disease (Plasmacytosis) is caused by the Aleutian mink disease virus (AMDV), an autonomous parvovirus and affects many mustelid species, including the American mink (Neovisonvison). In Denmark, an eradication program reduced the prevalence of test-positive farms from 100% in 1976 to 15% in 1996. Nevertheless, the disease persists in the Vendsyssel district of Northern Jutland, despite the eradication efforts. In this study, we used spatial epidemiological analysis to test for spatial autocorrelation of the distribution of farms positive for the disease. We investigated 2375 farms in Denmark (342 of which were located in the Vendsyssel district), during the period 2000-2008. For the purpose of our study, a farm was considered positive when, on any test conducted in a year, at least three animals were tested positive. To detect spatial clusters, we performed a retrospective analysis with spatial scan statistics. We performed one analysis for each of the nine years (2000-2008). A separate analysis was conducted with only the farms in Vendsyssel included. The spatial cluster analysis revealed a significant cluster throughout the time period studied in Northern Jutland. The only exception was 2002 when an outbreak was detected in the southern part of Jutland, and not in the north. The farm-level prevalence of the disease in Denmark was highest in this year, suggesting that the outbreak in the south could have masked the persistent signal from the north; the northern cluster was still significant when analysing only the Vendsyssel populations. These results confirm that Northern Jutland continues to have a significantly higher number of cases than expected if the disease was randomly distributed. 相似文献
48.
We conducted an on-line questionnaire to assess stakeholder perceptions about damage to silo bags by vertebrate species in Argentina. We received 190 responses reporting damage to silo bags by vertebrates from the Pampas, Espinal, and Chaco regions. More than two-thirds of respondents indicated armadillos were the main harmful species, followed by rodents and dogs. Frequency of damage to silo bags was higher for armadillos (79%) than for the other species together (64%), and was higher in the Pampas (79%) than in the other regions (45–66%), suggesting a latitudinal gradient of damage. Economic losses were reported as “medium” or “high” by 37% of respondents. According to these stakeholders, damage to silo bags by vertebrates is a regionally extended phenomenon in most of the Argentine agricultural region and it is recognized as economically relevant by these stakeholders. Management of this conflict should focus on environmental aspects. 相似文献
49.
K. Kocsis Z. Benyeda I. Bódi D. Molnár N. Nagy N. Fejszák 《British poultry science》2012,53(3):397-400
1. CVI-ChNL 74·3, a dendritic cell-specific monoclonal antibody (mAb) also identifies chicken lung granular pneumocytes (type II pneumocytes), which produce surfactant.
2. The 74·3 mAb does not cross-react with any other avian or mammalian granular pneumocyte, and provides a convenient tool for monitoring the status of type II pneumocytes in the chicken lung. 相似文献
50.
Corrêa AP Dossi AC de Oliveira Vasconcelos R Munari DP de Lima VM 《Veterinary parasitology》2007,143(3-4):267-274
The aims of this study were to evaluate the immunomodulatory role of TGF-β1, IL-10, and INF-γ in spleen and liver extracts and supernatant cultures of white spleen cells from male symptomatic and asymptomatic dogs, naturally infected by Leishmania (Leishmania) chagasi. Thirty dogs from Araçatuba, São Paulo, Brazil, an endemic leishmaniosis area, were selected by positive ELISA serological reaction for Leishmania sp. and divided into two groups: asymptomatic (n = 15) and symptomatic (n = 15) consisting of animals with at least three characteristic signs (fever, dermatitis, lymphoadenopathy, onychogryphosis, weight loss, cachexia, locomotion problems, conjunctivitis, epistaxis, hepatosplenomegaly, edema, and apathy). After euthanasia, spleen and liver fragments were collected for ex vivo quantification of TGF-β1, IL-10, and INF-γ. Naturally active in vitro produced TGF-β1 was also evaluated in spleen cell culture supernatant. Spleen and liver extract of asymptomatic dogs had higher mean TGF-β1 levels than symptomatic dogs. High concentrations of IL-10 were found in spleen, and mainly in liver extract of both groups. Higher INF-γ concentrations were found in spleen extracts of symptomatic dogs, and in liver extracts of asymptomatic dogs. Extract of this cytokine was lower in spleen extract. Although INF-γ is being produced in canine infection, mean levels of TGF-β1 and IL-10 from spleen and liver extracts were quantitatively much higher; suggesting that immune response in both asymptomatic and symptomatic dogs was predominantly type Th2. 相似文献