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1.
Raghavendra G Amachawadi Wesley A Tom Michael P Hays Samodha C Fernando Philip R Hardwidge T G Nagaraja 《Journal of animal science》2021,99(4)
Liver abscesses in feedlot cattle are polymicrobial infections. Culture-based studies have identified Fusobacterium necrophorum as the primary causative agent, but a number of other bacterial species are frequently isolated. The incidence of liver abscesses is highly variable and is affected by a number of factors, including cattle type. Holstein steers raised for beef production have a higher incidence than crossbred feedlot cattle. Tylosin is the commonly used antimicrobial feed additive to reduce the incidence of liver abscesses. The objective of this study was to utilize 16S ribosomal RNA amplicon sequence analyses to analyze the bacterial community composition of purulent material of liver abscesses of crossbred cattle (n = 24) and Holstein steers (n = 24), each fed finishing diet with or without tylosin. DNA was extracted and the V3 and V4 regions of the 16S rRNA gene were amplified, sequenced, and analyzed. The minimum, mean, and maximum sequence reads per sample were 996, 177,070, and 877,770, respectively, across all the liver abscess samples. Sequence analyses identified 5 phyla, 14 families, 98 genera, and 102 amplicon sequence variants (ASV) in the 4 treatment groups. The dominant phyla identified were Fusobacteria (52% of total reads) and Proteobacteria (33%). Of the top 25 genera identified, 17 genera were Gram negative and 8 were Gram positive. The top 3 genera, which accounted for 75% of the total reads, in the order of abundance, were Fusobacterium, Pseudomonas, and Bacteroides. The relative abundance, expressed as percent of total reads, of phyla, family, and genera did not differ (P > 0.05) between the 4 treatment groups. Generic richness and evenness, determined by Shannon–Weiner and Simpson’s diversity indices, respectively, did not differ between the groups. The UniFrac distance matrices data revealed no clustering of the ASV indicating variance between the samples within each treatment group. Co-occurrence network analysis at the genus level indicated a strong association of Fusobacterium with 15 other genera, and not all of them have been previously isolated from liver abscesses. In conclusion, the culture-independent method identified the bacterial composition of liver abscesses as predominantly Gram negative and Fusobacterium as the dominant genus, followed by Pseudomonas. The bacterial community composition did not differ between crossbred and Holstein steers fed finishing diets with or without tylosin. 相似文献
2.
Seroprevalence of Peste des petits ruminants in cattle and buffaloes from Southern Peninsular India 总被引:1,自引:1,他引:0
Balamurugan V Krishnamoorthy P Veeregowda BM Sen A Rajak KK Bhanuprakash V Gajendragad MR Prabhudas K 《Tropical animal health and production》2012,44(2):301-306
This study describes seroprevalence of Peste des petits ruminants (PPR) in cattle and buffaloes carried out during the period 2009–2010 using the randomly collected serum samples from different
parts of Southern peninsular India. The report presents the results of PPR virus (PPRV)—specific antibodies in situations
where either the subclinical or inapparent or non-lethal infection was there in cattle and buffaloes. A total of 2,548 serum
samples [cattle = 1,158, buffaloes = 1,001, sheep = 303 and goat = 86] were collected and screened for PPRV antibodies by
using a PPR monoclonal antibody-based competitive ELISA kit. Analysis of 2,159 serum samples indicates an overall 4.58% prevalence
of PPRV antibody in cattle and buffaloes. The presence of PPRV-specific antibodies demonstrates that cattle and buffaloes
are exposed to PPR infection naturally, and the transmission mode may be direct or indirect. Further, it implies the importance
of bovines as subclinical hosts for the virus besides widespread presence of the disease in sheep and goats in the country. 相似文献
3.
Sivakumar K. Chamarthi Kundan Kumar Raghavendra Gunnaiah Ajjamada C. Kushalappa Yves Dion Thin M. Choo 《European journal of plant pathology / European Foundation for Plant Pathology》2014,138(1):67-78
Fusarium head blight (FHB) and deoxynivalenol (DON) mycotoxin produced by Fusarium graminearum reduce barley yield and quality worldwide. Hundreds of quantitative trait loci (QTLs) have been identified in wheat and barley but their functions are largely unknown. Metabolic profiling was applied to better understand the mechanisms of resistance and to identify potential FHB resistance biomarker metabolites in barley. Four FHB resistant (H15-2, H148-3, H203-2 and H379-2) and one susceptible (H97-2), two-row, purple, doubled-haploid (DH) lines of barley were inoculated with either the pathogen or mock-solution. The disease severity quantified as the area under the disease progress curve (AUDPC) significantly varied between the resistant and susceptible genotypes, but not among the resistant genotypes. Neither the amount of DON nor the detoxified product, proportion of total DON, was significant among lines. The resistance related (RR, higher in abundance in resistant than in susceptible) metabolites varied in numbers and fold changes among the DH resistant lines. A total of 144 RR constitutive (RRC) and 167 RR induced (RRI) metabolites were selected, of which 39 and 37, respectively, were putatively identified. These RR metabolites mainly belonged to six chemical groups: phenylpropanoids, hydroxycinnamic acid amides, flavonoids, fatty acids, terpenoids, and alkaloids. The specific RR metabolites identified in each DH line, the possible mechanisms of resistance in each and their use as potential biomarkers are discussed. 相似文献
4.
Varshney Richa Poornesha B. Raghavendra A. Lalitha Y. Apoorva V. Ramanujam B. Rangeshwaran R. Subaharan K. Shylesha A. N. Bakthavatsalam N. Chaudhary Malvika Pandit Vinod 《植物病害和植物保护杂志》2021,128(1):87-95
Journal of Plant Diseases and Protection - Spodoptera frugiperda (J E Smith) (fall armyworm) (Lepidoptera: Noctuidae), is a key pest of maize that has recently entered in India causing damage and... 相似文献
5.
Rotenberg D Joshi R Benitez MS Chapin LG Camp A Zumpetta C Osborne A Dick WA Gardener BB 《Phytopathology》2007,97(6):756-766
ABSTRACT Analyses of multiple field experiments indicated that the incidence and relative abundance of root-colonizing phlD+ Pseudomonas spp. were influenced by crop rotation, tillage, organic amendments, and chemical seed treatments in subtle but reproducible ways. In no-till corn plots, 2-year rotations with soybean resulted in plants with approximately twofold fewer phlD+ pseudomonads per gram of root, but 3-year rotations with oat and hay led to population increases of the same magnitude. Interestingly, tillage inverted these observed effects of cropping sequence in two consecutive growing seasons, indicating a complex but reproducible interaction between rotation and tillage on the rhizosphere abundance of 2,4-diacetlyphloroglucinol (DAPG) producers. Amending conventionally managed sweet corn plots with dairy manure compost improved plant health and also increased the incidence of root colonization when compared with nonamended plots. Soil pH was negatively correlated to rhizosphere abundance of phlD+ pseudomonads in no-till and nonamended soils, with the exception of the continuous corn treatments. Chemical seed treatments intended to control fungal pathogens and insect pests on corn also led to more abundant populations of phlD in different tilled soils. However, increased root disease severity generally was associated with elevated levels of root colonization by phlD+ pseudomonads in no-till plots. Interestingly, within a cropping sequence treatment, correlations between the relative abundance of phlD and crop stand or yield were generally positive on corn, and the strength of those correlations was greater in plots experiencing more root disease pressure. In contrast, such correlations were generally negative in soybean, a difference that may be partially explained by difference in application of N fertilizers and soil pH. Our findings indicate that farming practices can alter the relative abundance and incidence of phlD+ pseudomonads in the rhizosphere and that practices that reduce root disease severity (i.e., rotation, tillage, and chemical seed treatment) are not universally linked to increased root colonization by DAPG-producers. 相似文献
6.
Velmurugan GV Tewari AK Rao JR Baidya S Kumar MU Mishra AK 《Veterinary parasitology》2008,154(3-4):185-192
Toxoplasmosis, caused by Toxoplasma gondii, is a disease of economic importance in livestock, especially in sheep and goats, where it causes abortion. Although several serological tests are in use for diagnosis of infection, production of reliable reagents is a constraint. An 814 bp sequence coding for a truncated surface antigen surface antigen 1 (SAG1), a tachyzoite stage-specific protein, as well as a 657 bp sequence coding for granule protein 7 (GRA7), a dense granule protein were PCR amplified from the genomic DNA of T. gondii. The amplified products were ligated in pET-32b(+) and pET-32c(+) expression vectors, respectively and subsequently transformed into BL21(DE3)pLysS cells. A high-level expression of the histidine-tagged SAG1 and GRA7 fusion proteins were obtained after 7h of incubation. The recombinant proteins were purified using Ni-NTA column and were characterized by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blot analysis using reference positive sera from goat, rabbit and humans at 1:100 dilution. Subsequently, the diagnostic efficiency of the recombinant proteins, either individually or as a cocktail of the recombinant proteins, was assessed with 56 reference goat sera by enzyme-linked immunosorbent assay (ELISA). The immunoreactivity of the refolded SAG1 and GRA7 was evidenced by high OD values. The reactivity of the recombinant proteins as a cocktail preparation was more than that of individual proteins in ELISA and could detect accurately the infection in goats. This is the first report of serological detection of caprine toxoplasmosis by ELISA using a cocktail of recombinant Toxoplasma proteins. 相似文献
7.
Identification and Characterization of Novel Genetic Markers Associated with Biological Control Activities in Bacillus subtilis 总被引:3,自引:0,他引:3
ABSTRACT Suppressive subtractive hybridization (SSH) was used to identify genetic markers associated with biological control of plant pathogens by Bacillus subtilis. The genomes of two commercialized strains, GB03 and QST713, were compared with that of strain 168, which has no defined biocontrol capacities, to obtain a pool of DNA fragments unique to the two biocontrol strains. The sequences of 149 subtracted fragments were determined and compared with those present in GenBank, but only 80 were found to correspond to known Bacillus genes. Of these, 65 were similar to genes with a wide range of metabolic functions, including the biosynthesis of cell wall components, sporulation, and antibiotic biosynthesis. Sixteen subtracted fragments shared a high degree of similarity to sequences found in multiple B. subtilis strains with proven biocontrol capacities. Oligonucleotide primers specific to nine of these genes were developed. The targeted genes included five genes involved in antibiotic synthesis (bmyB, fenD, ituC,srfAA, and srfAB) and four additional genes (yndJ, yngG, bioA, and a hypothetical open reading frame) not previously associated with biological control. All nine markers were amplified from the commercialized B. subtilis strains GB03, QST713, and MBI600, with the exception of ituC, which was not detected in GB03. The markers also were amplified from four other B. subtilis isolates, but they were not amplified from other related Bacillus strains, including the plant growth-promoting rhizobacteria IN937a and IN937b. Sequencing of the amplified markers revealed that all seven of the isolates that scored positive for multiple markers were genotypically distinct strains. Interestingly, strains scored positive for the amplifiable markers generally were more effective at inhibiting the growth of Rhizoctonia solani and Pythium ultimum than other Bacillus isolates that lacked the markers. The potential utility of the defined genetic markers to further define the diversity, ecology, and biocontrol activities of B. subtilis are discussed. 相似文献
8.
Zach Bohannan Raghavendra Sumanth Pudupakam Jamin Koo Harrison Horwitz Josephine Tsang Amanda Polley Enyang James Han Elmer Fernandez Stanley Park Deanna Swartzfager Nicholas Seah Xi Qi Chantal Tu Wendi Velando Rankin Douglas H. Thamm Hye‐Ryeon Lee Sungwon Lim 《Veterinary and comparative oncology》2021,19(1):160-171
We report a precision medicine platform that evaluates the probability of chemotherapy drug efficacy for canine lymphoma by combining ex vivo chemosensitivity and immunophenotyping assays with computational modelling. We isolated live cancer cells from fresh fine needle aspirates of affected lymph nodes and collected post‐treatment clinical responses in 261 canine lymphoma patients scheduled to receive at least 1 of 5 common chemotherapy agents (doxorubicin, vincristine, cyclophosphamide, lomustine and rabacfosadine). We used flow cytometry analysis for immunophenotyping and ex vivo chemosensitivity testing. For each drug, 70% of treated patients were randomly selected to train a random forest model to predict the probability of positive Veterinary Cooperative Oncology Group (VCOG) clinical response based on input variables including antigen expression profiles and treatment sensitivity readouts for each patient's cancer cells. The remaining 30% of patients were used to test model performance. Most models showed a test set ROC‐AUC > 0.65, and all models had overall ROC‐AUC > 0.95. Predicted response scores significantly distinguished (P < .001) positive responses from negative responses in B‐cell and T‐cell disease and newly diagnosed and relapsed patients. Patient groups with predicted response scores >50% showed a statistically significant reduction (log‐rank P < .05) in time to complete response when compared to the groups with scores <50%. The computational models developed in this study enabled the conversion of ex vivo cell‐based chemosensitivity assay results into a predicted probability of in vivo therapeutic efficacy, which may help improve treatment outcomes of individual canine lymphoma patients by providing predictive estimates of positive treatment response. 相似文献
9.
D. B. Wankhede A. Shehnaj M. R. Raghavendra Rao 《Plant foods for human nutrition (Dordrecht, Netherlands)》1979,28(4):293-303
Carbohydrate make-up of different varieties (ie, Hamsa, Purna and Indof) of Finger millet(Eleusine coracana) and Foxtail millet(Setaria italica) has been studied. All the millets contain about 63 to 70% total carbohydrates of which, based on the whole grains, free sugars account for 0.46 to 0.69%, starch 56.0 to 61.0% cellulose 0.70 to 1.80%, pentosans 5.50 to 7.20%. 70% ethanol-extractable sugars were xylose (1.5 to 4.3%), fructose (8.6 to 15%), glucose (9.9 to 15%), sucrose (31 to 35%), maltose (9 to 11.0%), raffinose (8.6 to 12%), maltotriose (5 to 6.1%), unidentified components (3 to 10%) and higher oligosaccharides (5to 9%). The watersoluble gums of the millets contain arabinose and xylose as the major sugar components together with minor amounts of mannose and galactose, and varying amounts of glucose. Hemicellulose A was found to consist mainly of glucans containing arabinose and xylose in minor amounts. Hemicellulose B contained arabinose and xylose with smaller amounts of glucose and galactose. 相似文献
10.
Raghavendra Kerur Vishwanath Ramesh Kurubarahalli Bhoothanna Rachana Rajan Remani Mahendra Chowdanayak Singh Surender Kumar Chander Subhash 《Phytoparasitica》2023,51(2):227-239
Phytoparasitica - Thrips are economically important pests of crops and vectors of viral diseases worldwide. Invasion and outbreak of thrips have recently caused havoc in agricultural and... 相似文献