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Repeated physical and cytologic characterizations of subcutaneous postvaccinal reactions in cats.
1997
Schultze A.E. | Frank L.A. | Hahn K.A.
Properties of monoclonal antibodies against Berne virus (Toroviridae).
1989
Kaeffer B. | Kooten P. van | Ederveen J. | Eden W. van | Horzinek M.C.
Seven hybridomas that secreted monoclonal antibodies (MAB) against the peplomer protein and one that secreted MAB against the nucleocapsid protein of Berne virus (proposed family Toroviridae) were isolated. All MAB directed against the peplomer protein neutralized virus infectivity and, with the exception of MAB 6A7, inhibited each other's binding in competition assays. Neutralization of Berne virus infectivity was potentiated when some MAB were used in pairs. The antibodies have been used to localize toroviral proteins in infected cells; use of antipeplomer MAB 6B10 yielded a diffuse intracytoplasmic immunofluorescence, whereas the antinucleocapsid MAB 1F1 detected antigen in the intra- and perinuclear compartments. By use of radioimmune precipitation, protein A of Staphylococcus aureus was found to bind directly to the nucleocapsid polypeptide, without the requirement for specific antibody. Using fluorescein isothiocyanate-conjugated protein A, the intranuclear accumulation of the nucleoprotein of Berne virus was confirmed by results of immunofluorescence.
Mostrar más [+] Menos [-]Morphologic study of inclusions in tissues from pigs inoculated with cytomegalovirus.
1987
Narita M. | Kawamura H. | Shirai J. | Haritani M.
Characterization of osteosarcoma cells from two sibling large-breed dogs.
1989
Norrdin R.W. | Powers B.E. | Torgersen J.L. | Smith R.E. | Withrow S.J.
Neoplastic cells were isolated from 2 sibling Great Dane/Labrador Retriever mixed-breed dogs in which telangiectatic type osteosarcomas arose concurrently. Cells from various sites in the same osteosarcoma appeared similar in culture, but there were differences between the 2 osteosarcomas in growth characteristics and appearance of cells. Cells from 1 osteosarcoma had a small, but significant (P less than 0.05), cyclic adenosine monophosphate response to parathyroid hormone stimulation, indicating a low order of osteoblastic differentiation. Cells from the other osteosarcoma had no response to parathyroid hormone stimulation. Cells from both osteosarcomas and a concentrated cell-free filtrate from the osteosarcoma with osteoblastic differentiation were injected into nude mice, but osteosarcomas were not induced. Results of ultrastructural examination of osteosarcoma samples for viral particles were negative and supernatant fluids from cultured cells were considered negative for viral reverse transcriptase activity.
Mostrar más [+] Menos [-]Preparation of an inactivated penta cell culture vaccine against canine distemper, canine parvo, canine hepatitis "canine adeno-1", canine adeno-2 and rabies viruses for dogs
2005
Naglaa I. Aly | Zeinab T. S. Salama
A penta-dog inactivated cell culture vaccine was prepared to protect dogs againstcanine distemper virus, canine parvovirus, canine adenovirus1, 2 and rabies virus.The potency of this vaccine was compared with that of single inactivated vaccinesprepared against each disease, in different groups of susceptible dogs. It was foundthat the protective dose of penta-dog vaccine (2ml) including the protective amounts of the five viral proteins resulted in full protection of vaccinated dogs against the challenge with virulent strain of the used viruses showing no antagonizing effect between each other with and no adverse postvaccinal reaction. So, the prepared inactivated cell culture penta-dog vaccine is a safe and potent vaccine for dogs which resulted in saving time, cost, and effort stress factors on animals and providing good immune statues.
Mostrar más [+] Menos [-]Preparation and evaluation of combined inactivated vaccine containing rota, corona viruses, Escherichia coli bacterin and Clostridium perfringens type Ctoxoid (Entero-4)
2005
A. M. Daoud | R. A. Diab | S. M. Aboul Saoud | S. M. Zeidan | F. F. Zaki
A conclusive study was conducted for preparation and evaluation of combinedinactivated entero-4 vaccine containing bovine rotavirus (BRV), bovine coronavirus(BCV), E. coli K99 and toxoid of C. perfringens type "C". Laboratory and field evaluations were conducted on laboratory animals, calves and late pregnant cows with monitoring the active and passive antibodies in vaccinated cows and their offspring respectively. Laboratory evaluation proved purity, safety and high efficacy of the vaccine without interference between different vaccine ingredients. Field evaluation gave satisfactory results when pregnant cows vaccinated at late stage of pregnancy with high neutralizing antibody titers against BRV, BCV and C. perfringens as well as high E. coli agglutinating titers. Maternal immunity passively protected offspring during the critical period of age and remained protected till the end of sampling time (30th day post parturition).
Mostrar más [+] Menos [-]Highly pathogenic avian influenza H5Nx in Poland in 2020/2021: a descriptive epidemiological study of a large-scale epidemic
2022
Śmietanka, Krzysztof | Świętoń, Edyta | Wyrostek, Krzysztof | Kozak, Edyta | Tarasiuk, Karolina | Styś-Fijoł, Natalia | Dziadek, Kamila | Niemczuk, Krzysztof
Highly pathogenic avian influenza (HPAI) outbreaks caused by the Gs/Gd lineage of H5Nx viruses occur in Poland with increased frequency. The article provides an update on the HPAI situation in the 2020/2021 season and studies the possible factors that caused the exceptionally fast spread of the virus. Samples from poultry and wild birds delivered for HPAI diagnosis were tested by real-time RT-PCR and a representative number of detected viruses were submitted for partial or full-genome characterisation. Information yielded by veterinary inspection was used for descriptive analysis of the epidemiological situation. The scale of the epidemic in the 2020/2021 season was unprecedented in terms of duration (November 2020–August 2021), number of outbreaks in poultry (n = 357), wild bird events (n = 92) and total number of affected domestic birds (approximately ~14 million). The major drivers of the virus spread were the harsh winter conditions in February 2020 followed by the introduction of the virus to high-density poultry areas in March 2021. All tested viruses belonged to H5 clade 2.3.4.4b with significant intra-clade diversity and in some cases clearly distinguished clusters. The HPAI epidemic in 2020/2021 in Poland struck with unprecedented force. The conventional control measures may have limited effectiveness to break the transmission chain in areas with high concentrations of poultry.
Mostrar más [+] Menos [-]Mink SARS-CoV-2 infection in Poland – short communication
2021
Domańska-Blicharz, Katarzyna | Orłowska, Anna | Smreczak, Marcin | Niemczuk, Krzysztof | Iwan, Ewelina | Bomba, Arkadiusz | Lisowska, Anna | Opolska, Justyna | Trębas, Paweł | Potyrało, Patrycja | Kawiak-Sadurska, Magdalena | Rola, Jerzy
Since April 2020, when the first SARS-CoV-2 infection was reported in mink and subsequently in mink farm workers in the Netherlands, it has been confirmed that human-to-mink and mink-to-human transmission can occur. Later, SARS-CoV-2 infections in mink were reported in many European and North American countries. Samples from 590 mink from a total of 28 farms were tested by real-time RT-PCR. Whole genome sequences from one positive farm were generated and genetic relatedness was established. SARS-CoV-2 RNA was detected on a breeder farm with stock of 5,850 mink. Active viraemia was confirmed in individually tested samples with Ct values respectively between 19.4 and 29.6 for E and N gene fragments. Further testing of samples from culled animals revealed 70% positivity in throat swabs and 30% seropositivity in blood samples. Phylogenetic analysis of full-length nucleotide sequences of two SARS-CoV-2 isolates revealed that they belong to the 20B Nextstrain clade. Several nucleotide mutations were found in analysed samples compared to the reference Wuhan HU-1 strain and some of them were nonsynonymous. We report the infection of mink with SARS-CoV-2 on one farm in Poland and the results of subsequent analysis of virus sequences from two isolates. These data can be useful for assessment of the epidemiological situation of SARS-CoV-2 in Poland and how it endangers public health.
Mostrar más [+] Menos [-]Models to assess the risk of introduction of selected animal viral diseases through the importation of live animals as a key part of risk analysis
2021
Gierak, Anna | Śmietanka, Krzysztof
Introduction of an animal viral disease, especially a notifiable disease, into an importing country or region free from the disease may lead to serious epidemiological consequences and economic losses. Trade in live animals is historically considered one of the most important risk pathways. To estimate the magnitude of such risk, the likelihood of a virus’ entry into a country and the consequences of this event should be jointly evaluated. Depending on data availability, the urgency of the problem and the detail level of the objectives, a risk assessment may be conducted in a qualitative, semi-quantitative or quantitative way. The purpose of this review was firstly to provide a brief description of each step of the risk analysis process, with particular emphasis on the risk assessment component, and subsequently to supply examples of different approaches to the assessment of the risk of the introduction of selected animal viral diseases. Based on the reviewed models, the overall likelihood of introduction of particular diseases was generally estimated as low. The output risk value was strongly dependent on the duration of the silent phase of the epidemic in the country of origin. Other parameters with some bearing upon the risk derived from the epidemiological situation in the country of origin and the biosecurity or mitigation measures implemented in the country of destination. The investigated models are universal tools for conducting assessment of the risk of introduction of various animal diseases to any country. Their application may lead to timely implementation of appropriate measures for the prevention of the spread of a disease to another country or region.
Mostrar más [+] Menos [-]Regional distribution of non-human H7N9 avian influenza virus detections in China and construction of a predictive model
2021
Huang, Zeying | Li, Haijun | Huang, Beixun
H7N9 avian influenza has broken out in Chinese poultry 10 times since 2013 and impacted the industry severely. Although the epidemic is currently under control, there is still a latent threat. Epidemiological surveillance data for non-human H7N9 avian influenza from April 2013 to April 2020 were used to analyse the regional distribution and spatial correlations of positivity rates in different months and years and before and after comprehensive immunisation. In addition, positivity rate monitoring data were disaggregated into a low-frequency and a high-frequency trend sequence by wavelet packet decomposition (WPD). The particle swarm optimisation algorithm was adopted to optimise the least squares support-vector machine (LS-SVM) model parameters to predict the low-frequency trend sequence, and the autoregressive integrated moving average (ARIMA) model was used to predict the high-frequency one. Ultimately, an LS-SVM-ARIMA combined model based on WPD was constructed. The virus positivity rate was the highest in late spring and early summer, and overall it fell significantly after comprehensive immunisation. Except for the year 2015 and the single month of December from 2013 to 2020, there was no significant spatiotemporal clustering in cumulative non-human H7N9 avian influenza virus detections. Compared with the ARIMA and LS-SVM models, the LS-SVM-ARIMA combined model based on WPD had the highest prediction accuracy. The mean absolute and root mean square errors were 2.4% and 2.0%, respectively. Low error measures prove the validity of this new prediction method and the combined model could be used for inference of future H7N9 avian influenza virus cases. Live poultry markets should be closed in late spring and early summer, and comprehensive H7N9 immunisation continued.
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