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Acta Veterinaria Hungarica
Authors:
Ž. Cvetnić
,
S. Špičić
,
M. Benić
,
Vera Katalinić-Janković
,
Mateja Pate
,
B. Krt
, and
M. Ocepek

During a five-year period (2000 to 2004) 74,342 pigs were tested by the intradermal tuberculin test in Croatia. Of them, 248 (0.33%) pigs were positive and 91 (0.12%) were found to be suspicious in 7 out of the 13 farms included in the study. Gross pathological changes characteristic of tuberculosis were observed in tuberculin-positive and/or suspicious swine. Mycobacterium was isolated from the lymph nodes of 183 out of 234 swine (78.2%). For better epidemiological understanding, isolates were typed by conventional methods, PCR and hybridisation. The results show that most of the isolates belonged to the Mycobacterium avium complex (175 isolates, 95.7%). Other isolates belonged to M. fortuitum (6 isolates, 3.3%), M. chelonae (1 isolate, 0.5%), and M. peregrinum (1 isolate, 0.5%). Isolated strains of the M. avium complex were identified as M. a. avium (37 isolates, 21.1%) and M. a. hominissuis (138 isolates, 78.9%).

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Yellow mosaic and leaf curling symptoms were observed on Ageratum conyzoides plants in a survey made during 2007–09 at Gorakhpur and nearby locations of North-Eastern Uttar Pradesh, India. The incident of disease was significantly high with severe symptoms. Due to presence of whiteflies in the field, begomovirus infection was suspected. Therefore, polymerase chain reaction (PCR) was performed with begomovirus specific primers (TLCV-CP). Total genomic DNA was isolated from infected as well as healthy leaf samples. In gel electrophoresis an ∼800 bp amplicon was obtained in diseased leaf samples as expected, while no amplicon was found in healthy plants.Amplicons obtained were directly sequenced and submitted to the GenBank with the accession number GQ412352 and a phylogeny tree was constructed with the available sequences in the Genbank. Based on the highest nucleotide similarity (98%), amino acid similarity and close relationship with isolates of Ageratum enation virus, the present isolate was considered as an isolate of Ageratum enation virus.

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Climate changes in Europe, which is characterized by the decrease of rainy days and the higher average temperature at summer, significantly increase the spreading of Aspergillus species and aflatoxin B1 contamination of the staple food and feed materials. The aim of our study was to estimate the possibility of the aflatoxin production of the Aspergilli on crops. From the isolates that were gained from crop samples, higher than 40% of the Aspergillus isolates contained norA, aflR and omtA genes from the aflatoxin genes cluster. Most of these isolates (63%) showed high homology with A. flavus, while three isolates showed high homology to A. tritici/A. candidus, one to A. cristatus/A. amstelodami and one strain showed the highest homology to A. tritici. Six from the A. flavus isolates (85.7%) with norA, aflR and omtA genes could produce aflatoxin B1 on malate extract agar medium. Parallel PCR and toxin measurements are recommended to evaluate the potentiality of aflatoxin production.

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Acta Veterinaria Hungarica
Authors:
Andreas Palzer
,
Rose-Leah Austin-Busse
,
Andrea Ladinig
,
Gyula Balka
,
Joachim Spergser
, and
Mathias Ritzmann

This study aimed to test the efficacy of samplings for the detection of Haemophilus parasuis after metaphylactic treatment and subsequent challenge using an established model for Glässer’s disease. In this model, 36 piglets were equally assigned to a negative control, a positive control, and two trial groups receiving tulathromycin 7 or 4 days prior to challenge. The piglets of three groups were challenged intratracheally with H. parasuis serovar 5. As a result, four pigs in each challenged group died or had to be euthanised within 10 days post challenge. The remaining 15 pigs of these challenged groups survived until termination of the experiment (days 14–15). All pigs were necropsied and collective swabs of serosal surfaces were tested by bacterial culture and PCR. Samples of tarsal synovial fluid and joint capsule, cerebrospinal fluid (CSF) and brain swabs were tested by PCR. A total of 22 out of the 27 challenged animals had macroscopically detectable polyserositis and all of them tested positive in the collective swab samples. Haemophilus parasuis was more frequently detected in pigs that died within the first 10 days compared to those surviving until days 14–15 (P < 0.001), and those that succumbed within 10 days showed higher positivity rates in the brain and CSF. All pigs which were positive in the CSF had detectable meningitis. At days 14–15, joint samples from 5 of the remaining 15 pigs tested positive for H. parasuis. Four of these five animals did not show any macroscopic or histological lesions in the joints. In conclusion, collective swabs were the best sample material in acute cases, whereas samples from the joints gave the best results in chronic cases. In this challenge model it was not possible to prove the metaphylactic effect of tulathromycin administered 4 and 7 days prior to infection with H. parasuis.

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Partial genome sequence of a herpes-like virus, isolated from Siberian sturgeon ( Acipenser baeri ), was determined and subjected to phylogenetic analysis. The virus (SbSHV) has been shown to be the causative agent of an acute disease with high mortality in farmed juvenile sturgeons in Russia. Two fragments (of 7000 and 300 base pairs in length) encompassing 3 complete and 3 partial ORFs were amplified by PCR. Sturgeon herpesvirus strains, classified into species Acipenserid herpesvirus 2 (AciHV-2), have been isolated and partially sequenced from several regions (California, Idaho, Oregon and Canada) of North America from white ( A. transmontanus) and shortnose sturgeons ( A. brevirostrum ). The sequence of the SbSHV strain shared highest identity with that of the Canadian strain originating from shortnose sturgeon. The phylogenetic analysis also confirmed that SbSHV is closely related to AciHV-2 and could also be classified into this virus species. This is the first report on the occurrence of AciHV-2 in Europe. Previously, only another virus species, AciHV-1 has been detected in farmed white sturgeons in Italy. The size and position of ORFs in the examined gene block confirmed that this genomic region is highly conserved in members of the genus Ictalurivirus .

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Infectious bursal disease virus is an important poultry pathogen. It is distributed worldwide and causes significant economic losses. In this study, a system was adopted for the simultaneous monitoring of vaccine and virulent strains using reverse transcription polymerase chain reaction (RT-PCR). After the decay of maternal antibodies, chickens were vaccinated at the age of 37 days with a virus of intermediate virulence and challenged at 5, 10 and 14 days post vaccination (dpv). The challenge was done with IBDV strain CH/99. Sequencing of the hypervariable region of VP2 has shown that CH/99 belongs to the very virulent group of viruses. The vaccine virus could be found in the bursa of Fabricius, spleen, thymus and bone marrow until 24 dpv. The CH/99 challenge virus was found in the bursa and lymphoid organs when chickens were challenged at 5 and 10 dpv. When challenge was performed at 14 dpv, the pathogenic virus could not be found in the bursa and other lymphoid organs.

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Acta Veterinaria Hungarica
Authors:
L. Sámi
,
Krisztina Ursu
,
J. McKillen
,
S. Kecskeméti
,
S. Belák
, and
I. Kiss

Specific oligonucleotide primers were selected and combined in a multiplex arrangement, in order to detect simultaneously three economically important porcine viruses by polymerase chain reaction (PCR). The pathogen panel was comprised of viruses that cause reproductive failure in infected herds: Aujeszky’s disease virus (ADV), porcine parvovirus (PPV) and porcine respiratory and reproductive syndrome virus (PRRSV). In order to reduce the time required for the detection of the pathogens, the assay was optimised to a RapidCycler PCR instrument. The multiplex PCR assay was shown to be specific, sensitive and rapid, because the results were read in less than 60 min after sample preparation. Due to its speed, efficiency and sensitivity, the described rapid multiplex PCR assay serves as a useful novel tool in the veterinary diagnostic laboratories for the quick and complex detection of these important porcine pathogens.

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For the molecular detection of Treponema pallidum authors introduced and used a nested PCR amplifying a conservative portion of the gene coding for the Tp 47 kDa membrane protein. PCR verified the presence of T. pallidum specific DNA in 5.7 per cent of syphilis seronegative 105 MSM belonging to HIV risk group. Treponema DNA was also detected in HIV infected, syphilis seronegative cases. Specificity of the method was demonstrated in rabbit inoculation test and also in clinically positive syphilis cases.

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biochemical tests without adequate laboratory testing is not possible as pathogen-specific clinical symptoms are lacking. The introduction of molecular-based detection methods such as polymerase chain reaction (PCR) and real-time PCR assays that are sensitive

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A survey was conducted to evaluate the presence and prevalence of Porcine Bocavirus (PBoV) in Croatian domestic pigs by means of PCR targeting the NS1 gene fragment of PBoV. This study included testing of faecal samples collected from 10 small commercial farms and 11 small backyard holdings in Croatia. The presence of PBoV was confirmed by PCR in 24 out of 57 composite faecal samples from small commercial farms and in 12 out of 43 composite faecal samples from small backyard holdings. The PCR products of 18 positive samples were sequenced for genotyping. PBoV sequences grouped into the PBoV-a, PBoV-b and PBoV-c groups with 90.81% to 99.25% nucleotide identity. All Croatian PBoV sequences showed a high nucleotide and amino acid identity with PBoV sequences from China and Hong Kong, the United States, Sweden, and Slovenia. These results clearly show that PBoV is circulating among the domestic pig population in Croatia.

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