Porcine Health Manag
July 2024
Background: Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is a significant swine pathogen, yet the immune response components contributing to protection remain incompletely understood. Broadly reactive neutralizing antibodies (bNAs) may play a crucial role in preventing reinfections by heterologous viruses, although their occurrence is considered low under both field and experimental conditions. This study aimed to assess the frequency of sows exhibiting bNAs against PRRSV under field conditions and to analyze the epidemiological factors influencing the occurrence of these elite neutralizers.
View Article and Find Full Text PDFPorcine reproductive and respiratory syndrome (PRRS) is considered one of the most relevant diseases of swine. The condition is caused by PRRS virus (PRRSV), an extremely variable virus of the family. Its heterogeneity can be responsible, at least partially, of the poor cross-protection observed between PRRSV isolates.
View Article and Find Full Text PDFCD169 and CD163 have been involved in the process of PRRS virus attachment and infection in macrophages, although recent studies have challenged the requirement for CD169. In addition to CD169, macrophages express other siglecs, whose role in PRRS virus infection is so far unknown. Splenic CD163 macrophages express Siglec-3 and Siglec-5 but almost undetectable levels of CD169.
View Article and Find Full Text PDFThe objective of this study was to compare the safety of all modified live virus vaccines commercially available in Europe against Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) under the same experimental conditions. For this purpose, one hundred and twenty three-week-old piglets, divided into five groups, were used. On day 0 of the experiment, nine pigs per group were removed and the remaining fifteen were vaccinated with the commercial vaccines Ingelvac PRRS MLV, Amervac PRRS, Pyrsvac-183 and Porcilis PRRS by the IM route or were mock vaccinated and used as controls.
View Article and Find Full Text PDFPorcine Reproductive and Respiratory Syndrome Virus (PRRSV) is highly heterogenic. This heterogeneity has an effect on antigenic composition of PRRSV and might create differences in sensitivity to neutralization between isolates. The sensitivity to neutralization could be an important feature of PRRSV isolates because it is likely that isolates resistant to neutralization pose a significant challenge for the development of vaccines that elicit broad protective immunity.
View Article and Find Full Text PDFVet J
September 2011
Disease exacerbation was observed in pigs challenged with virulent porcine reproductive and respiratory syndrome virus (PRRSV) following immunisation with a recombinant GP5 sub-unit PRRSV vaccine (rGP5) produced in E. coli. Eighteen animals were divided into three experimental groups: group A were immunised twice IM with rGP5, 21 days apart; group B acted as positive controls (challenged but not immunised); and group C were negative controls.
View Article and Find Full Text PDFThe aim of the present study was to establish the degree of diversity of porcine reproductive and respiratory virus (PRRSV) isolates that circulate in the same geographical area in different years. Nucleotide sequences of open reading frame (ORF) 5 were determined for 28 Spanish field PRRSV isolates from different years and three European-type modified live virus vaccines. Sequences were aligned using Clustal W software and a phylogenetic tree constructed using the neighbour joining method.
View Article and Find Full Text PDFThe objective of this study was to determine the degree of protection conferred by a Lelystad-like modified live virus (MLV) vaccine against a heterologous wild-type porcine reproductive and respiratory syndrome virus (PRRSV) isolate of the same cluster. For this purpose, fourteen 3-week-old piglets were divided into three groups: Group A pigs were vaccinated with a modified live virus vaccine, Group B pigs were used as positive controls, and Group C pigs as negative controls. Twenty-eight days after the last dose of vaccine, all pigs in Groups A and B were inoculated with the Spanish PRRSV strain 5710.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
November 2006
An unusual Gram-negative, catalase- and oxidase-positive, rod-shaped bacterium isolated from different clinical samples from two monkeys (Callithrix geoffroyi) was characterized by phenotypic and molecular genetic methods. The micro-organism was tentatively identified as a Pseudomonas species on the basis of the results of cellular morphological and biochemical tests. Fatty acid studies confirmed this generic placement and comparative 16S rRNA gene sequencing studies demonstrated that the unknown isolates were phylogenetically closely related to each other (100% sequence similarity) and were part of the 'Pseudomonas fluorescens intrageneric cluster'.
View Article and Find Full Text PDFThe objective of this study was to evaluate the efficacy of two commercially available modified live virus vaccines for preventing the reproductive and early postnatal consequences of infecting (challenging) pregnant gilts with virulent porcine reproductive and respiratory syndrome virus (PRRSV). For this purpose 21 crossbred gilts were allocated to one or another of four groups (Groups A-D). Group A comprised four gilts neither vaccinated nor challenged; Group B comprised five gilts that were challenged but not vaccinated; Group C comprised seven gilts that were vaccinated (AmervacPRRS) and challenged; Group D comprised five gilts that were vaccinated (Pyrsvac-183) and challenged.
View Article and Find Full Text PDFWe report a case of bacteremia in puppies caused by Streptococcus dysgalactiae subsp. dysgalactiae. Identification was achieved by phenotypic and molecular genetic methods.
View Article and Find Full Text PDFThe purpose of this study was to assess the effects of two currently available commercial European-type modified-live virus (MLV) vaccines against porcine reproductive and respiratory syndrome in a reproductive pig model. Sixteen 90-day pregnant gilts were divided into four groups and allocated to one of the following intranasal treatments: group A gilts served as negative controls; group B gilts were exposed to a virulent European field strain; group C gilts were exposed to vaccine strain VP046 Bis and group D gilts to vaccine strain All-183. The results indicated that MLV strains can replicate in breeding animals and have the ability to cross the placenta.
View Article and Find Full Text PDFPorcine reproductive and respiratory syndrome virus (PRRSV) has been reported to be shed in the semen of infected boars. To determine whether the reproductive tissues could be a persistent source of virus and the possible origin of PRRSV found in semen of infected boars, 20 PRRSV-seronegative boars were intranasally inoculated with 5 x 10(6) median tissue culture infective doses (TCID50) of PRRSV and necropsied at different times post-inoculation (p.i.
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