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Comparative study of leptospiral strains ictero No. 1 and RGA by restriction endonuclease DNA analysis.
1988
Hata K. | Yamaguchi T. | Ono E. | Yanagawa R.
Detection of bovine herpesvirus-1 nucleic acid sequences, using a dot-blot hybridization procedure.
1987
Andino R.H. | Torres H.N. | Polacino P.S. | Schudel A. | Palma E.L.
Pathological changes in natural infection of pheasants with highly pathogenic avian influenza A (H5N8) in Bulgaria
2019
Stoimenov, Georgi M. | Goujgoulova, Gabriela V. | Nikolov, Branimir | Hristov, Kalin | Teneva, Atanaska
The study of histopathological changes caused by influenza A (H5N8) viral infection in bird species is essential for the understanding of their role in the spread of this highly infectious virus. However, there are few such studies under natural conditions in minor gallinaceous species. This article describes the pathomorphological findings in Colchis pheasants infected naturally with H5N8 during an epizootic outbreak in Bulgaria. Samples of internal organs of 10 carcasses were collected for histopathological and immunohistochemical evaluation, virus isolation and identification, and nucleic acid detection. Consistent macroscopic findings were lesions affecting the intestine, heart, lung, and pancreas. Congestion and mononuclear infiltrate were common findings in the small intestine, as were necrosis and lymphoid clusters in the lamina propria of the caeca. Congestion with small focal necrosis and gliosis with multifocal nonpurulent encephalitis were observed in the brain. Myocardial interstitial oedema and degenerative necrobiotic processes were also detected. Immunohistological analysis confirmed systemic infection and revealed influenza virus nucleoprotein in all analysed organs. Variable necrosis was observed in the brain, liver, trachea, heart, small intestine, and caeca. Viral antigen was commonly found in the brain, heart, lung and trachea. Contact with migrating waterfowls was suspected as a reason for the outbreak.
Afficher plus [+] Moins [-]Exploration of the main sites for the transformation of normal prion protein (PrPC) into pathogenic prion protein (PrPsc)
2017
Liu, Xi-Lin | Feng, Xiao-Li | Wang, Guang-Ming | Gong, Bin-Bin | Ahmad, Waqas | Liu, Nan-Nan | Zhang, Yuan-Yuan | Yang, Li | Ren, Hong-Lin | Cui, Shu-Sen
Introduction: The functions and mechanisms of prion proteins (PrPC) are currently unknown, but most experts believe that deformed or pathogenic prion proteins (PrPSᶜ) originate from PrPC, and that there may be plural main sites for the conversion of normal PrPC into PrPSᶜ. In order to better understand the mechanism of PrPC transformation to PrPSᶜ, the most important step is to determine the replacement or substitution site. Material and Methods: BALB/c mice were challenged with prion RML strain and from 90 days post-challenge (dpc) mice were sacrificed weekly until all of them had been at 160 dpc. The ultra-structure and pathological changes of the brain of experimental mice were observed and recorded by transmission electron microscopy. Results: There were a large number of pathogen-like particles aggregated in the myelin sheath of the brain nerves, followed by delamination, hyperplasia, swelling, disintegration, phagocytic vacuolation, and other pathological lesions in the myelin sheath. The aggregated particles did not overflow from the myelin in unstained samples. The phenomenon of particle aggregation persisted all through the disease course, and was the earliest observed pathological change. Conclusion: It was deduced that the myelin sheath and lipid rafts in brain nerves, including axons and dendrites, were the main sites for the conversion of PrPC to PrPSᶜ, and the PrPSᶜ should be formed directly by the conversion of protein conformation without the involvement of nucleic acids.
Afficher plus [+] Moins [-]Detection and molecular analysis of bovine enteric norovirus and nebovirus in Turkey
2018
Turan, Turhan | Işıdan, Hakan | Atasoy, Mustafa Ozan | Irehan, Bünyamin
Bovine Norovirus (BoNeV) which has been confirmed in Asia, America, and Europe, seems to be distributed worldwide, even though only reported from a number of countries. Bovine noroviruses are predominantly detected in diarrhoeic animals rather than neboviruses. The study reveals the importance of noro- and neboviruses in early age diarrhoea of calves. A total of 127 stool samples were collected from three provinces located in the central region of Turkey. Samples were subjected to nucleic acid isolation and reverse transcription and polymerase chain reaction (PCR). Positive samples were sequenced and analysed. According to PCR, five samples (3.93%) were found to be positive for bovine norovirus while 32 (25.19%) samples were found to be positive for bovine nebovirus. Phylogenetic analysis indicated that the novel Turkish norovirus strains were found to be of genotype III.2 and all novel neboviruses were substituted under Nebraska-like strains. Although predominantly bovine noroviruses are detected worldwide, the study indicated that bovine neboviruses were more prevalent in the studied area. We suggest that bovine neboviruses are more frequently responsible for calf diarrhoea than supposed by virologists. This is also the first report of neboviruses other than Kirklareli virus which is distantly related to neboviruses detected in Turkey.
Afficher plus [+] Moins [-]Prevalence of antibodies to alcelaphine herpesvirus-1 and nucleic acid hybridization analysis of viruses isolated from captive exotic ruminants
1989
Seal, B.S. | Heuschele, W.P. | Klieforth, R.B.
A serologic survey was conducted to determine the prevalence of antibodies to alcelaphine herpesvirus-1 (AHV-1) in captive exotic ruminants within the United States. Forty-six percent of the members of the subfamily Alcelaphinae (wildebeest, topi, hartebeest) in the family Bovidae had virus-neutralizing antibody to AHV-1. Other subfamilies of Bovidae with high prevalence of virus-neutralizing antibodies to AHV-1 included Hippotraginae (oryx and addax) and Caprinae (sheep and goats), with prevalence of 45% and 29%, respectively. Herpesviruses that have been isolated from captive exotic ruminant species, including healthy animals and those with clinical malignant catarrhal fever at the Oklahoma City Zoo and the San Diego Zoo/Wild Animal Park, were analyzed by DNA restriction enzyme analysis and blot hybridization. Variation has been detected among the genomes of several malignant catarrhal fever virus isolates obtained from various exotic species of ruminants, using the DNA restriction enzymes BamHI and HindIII. The DNA of these virus isolates is distinct from that of bovine herpesviruses 1, 2, and 4, as demonstrated by restriction enzyme analysis and nucleic acid hybridization. On the basis of restriction enzyme analysis and nucleic acid hybridization data, the DNA from each of the putative alcelphine herpesvirus isolates examined, except for the topi virus isolate, had a high degree of DNA sequence similarity with the original AHV-1 isolate, WC-11, from a blue wildebeest.
Afficher plus [+] Moins [-]Detection of porcine encephalomyocarditis virus by in situ hybridization
1999
Oh, S.H. | Park, N.Y. | Chung, C.Y. | Cho, K.O. | Lee, B.J. | Park, Y.S. | Park, H.S. (Chonnam National University, Kwangju (Korea Republic). College of Veterinary Medicine)
The purpose of this study was to establish a rapid, reliable diagnostic method detecting Encephalomyocarditis virus(EMCV) RNA in formalin-fixed, paraffin-embedded tissues of EMCV naturally infected pigs by cDNA probe of EMC K3, the EMCV strain isolated from Korea. Using a biotin-labelled nick translated probe for the cDNA marker. We made up for some defects of radiolabeled method. In situ hybridization(ISH) technique, differently from theother nucleic acid hybridization methods, is able to detect the virus genome specifically in the state of the intact shapes of cells and/or tissues. We succeeded in performing the experiment to detect the EMCV within 1~2 hours usign the MicroProbeTM capaillary action system. In this study, we ovserved highly specific positive sighals of red color by staining the paraffinembedded tissue sections of naturally EMCV-infected pig organs or tissues, including brain, heart, kidney and lacrimal gland with the Fast Red TR salt/Naphtol phosphate chromogen. The results suggested that this ISH method is considered as a highly sensitive and reliable tool for molecular biologic diagnosis of the EMC viral disease.
Afficher plus [+] Moins [-]Antibody response of pseudorabies virus subunit-vaccinated pigs to viral nucleocapsid proteins following low-dose virus challenge of immunity
1989
McGinley, M.J. | Platt, K.B.
The antibody response to pseudorabies virus nucleocapsid proteins (NCP) was evaluated by the western immunoblot analysis before and after challenge of immunity by nasal inoculation of 10(2.3) plaque-forming units of virus in 10 pigs that had been vaccinated with pseudorabies virus envelope glycoproteins. Antibody to 5 NCP with molecular mass of 140, 63, 41, 34, and 23 kD was first detected in vaccinated and nonvaccinated pigs on day 14 after challenge of immunity. Antibody to 2 of the 5 NCP continued to be detected through day 113 in 9 of 10 vaccinated pigs. Beyond day 32, antibody to NCP was not detected in 1 vaccinated pig. The 23-, 34-, and 41-kD proteins were the most immunogenic. Antibody to each of these proteins was first detected on day 14 in 10, 10, and 8 pigs, respectively. Seven, 6, and 8 pigs, respectively, were antibody-positive for these proteins on day 113. The 140- and 63-kD proteins were the least immunogenic. Antibody to these proteins was detected in 8 and 9 pigs, respectively, on day 14, and in 4 and 5 pigs, respectively, on day 113. Chi-square analysis for dependency indicated that the antibody response to the 140- and 63-kD proteins was interdependent. These results suggested that combinations of NCP may be useful as non-vaccine diagnostic antigens.
Afficher plus [+] Moins [-]Caecal microflora composition in broilers fed sorghum based diets containing feed enzymes
2016
Asad, S. | Bryden, W. L. | Maguire, A. | Faizah H. M. S. | Klive, A. V. | Li, X.
This study was conducted to investigate whether dietary enzymes alter the caecal microbial profile of broilers fed sorghum-based diets. Four sorghum-based diets (918 g sorghum/kg diet) were prepared. One was the control diet and three had enzymes (xylanase, phytase andprotease) added. Broilers, 35-day-old, were reared (8 birds/cage) in an environmentally controlled shed and randomly allocated to replicated (n=4) assay diets and free access to feed and water all time. On day-42, birds were euthanized and caecal contents collected, pooled on a per/pen basis and frozen (-20 °C). The DNA was extracted from caecal samples using a bead-beating protocol and the V2V3 regionof the bacterial 16S rRNA gene amplified by PCR. Amplicons were separated on sequence difference using Denaturing Gradient Gel Electrophoresis (DGGE) and microbial profiles generated and compared.The DGGE profiles, when analysed, indicated that there was approximately 80% similarity between caecal microflora in all types of the diet treatments. This suggests that there was no overalldifference between any of the profiles and therefore the addition of different types of feed enzymes in a sorghum-based diet had no impact on the overall composition of the broiler caecal microflora.
Afficher plus [+] Moins [-]Collection and characterization of semen from Chilean rose tarantulas (Grammostola rosea)
2014
Archibald, Kate E. | Minter, Larry J. | Lewbart, Greg | Bailey, C Scott
Objective—To establish a nonterminal semen collection method for use in captive Chilean rose tarantulas (Grammostola rosea) and to evaluate tools for investigating morphology and viability of spermatozoa. Animals—7 mature male Chilean rose tarantulas. Procedures—Each tarantula was anesthetized in a 500-mL induction chamber containing a cotton ball infused with 2 mL of isoflurane. Semen collection was performed by applying direct pressure to the palpal bulbs (sperm storage organs) located on the distal segment of the palpal limbs. Morphology of spermatozoa was examined by light microscopy and transmission and scanning electron microscopy. Propidium iodide and a fluorescent membrane-permeant nucleic acid dye were used to evaluate cell viability. Results—Semen was collected successfully from all 7 tarantulas. Microscopic examination of semen samples revealed coenospermia (spherical capsules [mean ± SD diameter, 10.3 ± 1.6 μm] containing many nonmotile sperm cells [mean number of sperm cells/capsule, 18.5 ± 3.8]). Individual spermatozoa were characterized by a spiral-shaped cell body (mean length, 16.7 ± 1.4 μm; mean anterior diameter, 1.5 ± 0.14 μm). Each spermatozoon had no apparent flagellar structure. The fluorescent stains identified some viable sperm cells in the semen samples. Conclusions and Clinical Relevance—The described technique allowed simple and repeatable collection of semen from Chilean rose tarantulas. Semen from this species was characterized by numerous spherical capsules containing many nonmotile spermatozoa in an apparently quiescent state. Fluorescent staining to distinguish live from dead spermatozoa appeared to be a useful tool for semen evaluation in this species.
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