Comparative analysis of Pasteurella multocida strains isolated from bovine respiratory infections

Bovine respiratory disease (BRD) is the leading cause of significant economic losses in the intensive beef industry worldwide. Beside numerous risk factors Pasteurella multocida, which is regarded as a secondary pathogen, may play a role in the development of the disease. Previous studies of strainsfrom swine pneumonia revealed that there are a few clones associated with clinical disease, suggesting that some strains may be more virulent than others. This linkage may be true in the BRD, however composition of P. multocida populations in the herds are slightly characterized. Thus, we decided to perform phenotypic and genotypic characterisation of strains isolated from calves with respiratory infection at 31 different herds in Hungary. The results demonstrated the presence of two dominant strain types. At the identical taxonomic background (P. multocida subsp. multocida) with slight phenotypic variability they could be separated by trehalose fermentation capacity, α-glucosidase activity and molecular fingerprint patterns of ERIC- and M13-PCR. Independent prevalence and geographical origin of the strain types may refer to their significance in the illness, but their comparison with strains isolated from healthy individuals is taken into consideration

High mortality caused by Bibersteinia trehalosi septicaemia in adult sheep – A case report

The disease induced by Bibersteinia trehalosi usually occurs in lambs. It is triggered by certain stress factors and often emerges in the form of severe outbreaks. In adult sheep, only sporadic cases have been reported so far. This paper reports a B. trehalosi-induced high-mortality case occurring only in adult sheep. Seventy out of 628 adult sheep (11%) died in the affected pen during the six days of the outbreak. None of the 146 lambs kept in the neighbouring pen showed any clinical signs during that period. Several preceding events (shearing, vaccination and antiparasitic treatment) can be regarded as factors predisposing to the disease. Five adult sheep (4 females and 1 male) were sent for laboratory examination. Clinical, gross pathological, histological and bacteriological examinations revealed results corresponding to those reported previously in lambs that had died of a B. trehalosi-induced septicaemia

Antimicrobial susceptibility of Bacillus anthracis strains from Hungary

The susceptibility of 29 Bacillus anthracis strains, collected in Hungary between 1933 and 2014, was tested to 10 antibiotics with commercially available minimum inhibitory concentration (MIC) test strips. All strains were susceptible to amoxicillin, ciprofloxacin, clindamycin, doxycycline, gentamicin, penicillin, rifampicin, and vancomycin. Intermediate susceptibility to erythromycin and cefotaxime was detected in 17.2% (5/29) and 58.6% (17/29) of the strains, respectively. Correlations were not observed between the isolation date, location, host species, genotype, and antibiotic susceptibility profile of strains

First detection of Pasteurella multocida type B:2 in Hungary associated with systemic pasteurellosis in backyard pigs

This is the first report of Pasteurella multocida type B in Hungarian pigs. This disease was observed in backyard-raised pigs in three households within a small area. Neither the source of the infection nor the epidemiological connection between any of the premises could be determined. The most consistent lesion was dark red discolouration of the skin of the ventral neck and brisket, with accompanying oedema and haemorrhages. The morbidity was low and lethality relatively high, with three dead (50%) and two euthanised (33%) out of six affected animals. A total of three isolates of P. multocida (P55, P56 and P57) were cultured from these cases and examined in detail. These were identified as P. multocida ssp. multocida biovar 3. All were toxA negative and belonged to serotype B:2. Multilocus sequence typing was used to assign these to a new sequence type (ST61) that is closely related to other haemorrhagic septicaemia causing strains of P. multocida regardless of the host. M13 polymerase chain reaction and virulence-associated gene typing also show that type B strains form a highly homogeneous, distinct phylogenic group within P. multocida

Low incidence of Schmallenberg virus infection in natural cases of abortion in domestic ruminants in Hungary

An epizootic caused by a new orthobunyavirus called Schmallenberg virus (SBV) was recognised in European ruminants in 2011 and 2012. The re-emergence of the infection was reported in several countries in the subsequent years. Although the main clinical sign of SBV infection is abortion, the impact of SBV in natural cases of abortion in domestic ruminants had not been systematically examined before this study. The aim of the study was to investigate the role of SBV infection and to compare it to the importance of other causes of abortion by examining 537 natural cases of abortion that had occurred between 2011 and 2017 in Hungary. The cause of abortion was determined in 165 (31%) cases. An infectious cause was proved in 88 (16%) cases. SBV infection was found only in a total of four cases (0.8%) using real-time polymerase chain reaction. Three of them proved to be inapparent SBV infection, and one case was attributed to SBV-induced abortion by detecting non-purulent encephalitis and SBV nucleoprotein by immunohistochemistry in a brain tissue sample. According to the results, SBV played a minor role in natural cases of domestic ruminant abortion in Hungary during the 7-year period following the first SBV outbreak in 2011

First detection of Pasteurella multocida type B:2 in Hungary associated with systemic pasteurellosis in backyard pigs

This is the first report of Pasteurella multocida type B in Hungarian pigs. This disease was observed in backyard-raised pigs in three households within a small area. Neither the source of the infection nor the epidemiological connection between any of the premises could be determined. The most consistent lesion was dark red discolouration of the skin of the ventral neck and brisket, with accompanying oedema and haemorrhages. The morbidity was low and lethality relatively high, with three dead (50%) and two euthanised (33%) out of six affected animals. A total of three isolates of P. multocida (P55, P56 and P57) were cultured from these cases and examined in detail. These were identified as P. multocida ssp. multocida biovar 3. All were toxA negative and belonged to serotype B:2. Multilocus sequence typing was used to assign these to a new sequence type (ST61) that is closely related to other haemorrhagic septicaemia causing strains of P. multocida regardless of the host. M13 polymerase chain reaction and virulence-associated gene typing also show that type B strains form a highly homogeneous, distinct phylogenic group within P. multocida

MRSA Transmission between Cows and Humans

We isolated methicillin-resistant Staphylococcus aureus (MRSA) from cows with subclinical mastitis and from a person who worked with these animals. The bovine and human strains were indistinguishable by phenotyping and genotyping methods and were of a low frequency spa type. To our knowledge, this finding indicates the first documented case of direct transmission of MRSA between cows and humans

Phylogeny of Mycoplasma bovis isolates from Hungary based on multi locus sequence typing and multiple-locus variable-number tandem repeat analysis

BACKGROUND: Mycoplasma bovis is an important pathogen causing pneumonia, mastitis and arthritis in cattle worldwide. As this agent is primarily transmitted by direct contact and spread through animal movements, efficient genotyping systems are essential for the monitoring of the disease and for epidemiological investigations. The aim of this study was to compare and evaluate the multi locus sequence typing (MLST) and the multiple-locus variable-number tandem repeat (VNTR) analysis (MLVA) through the genetic characterization of M. bovis isolates from Hungary. RESULTS: Thirty one Hungarian M. bovis isolates grouped into two clades by MLST. Two strains had the same sequence type (ST) as reference strain PG45, while the other twenty nine Hungarian isolates formed a novel clade comprising five subclades. Isolates originating from the same herds had the same STs except for one case. The same isolates formed two main clades and several subclades and branches by MLVA. One clade contained the reference strain PG45 and three isolates, while the other main clade comprised the rest of the strains. Within-herd strain divergence was also detected by MLVA. Little congruence was found between the results of the two typing systems. CONCLUSIONS: MLST is generally considered an intermediate scale typing method and it was found to be discriminatory among the Hungarian M. bovis isolates. MLVA proved to be an appropriate fine scale typing tool for M. bovis as this method was able to distinguish closely related strains isolated from the same farm. We recommend the combined use of the two methods for the genotyping of M. bovis isolates. Strains have to be characterized first by MLST followed by the fine scale typing of identical STs with MLVA

First isolation and characterization of Brucella microti from wild boar

Background: Brucella microti was first isolated from common vole ( Microtus arvalis ) in the Czech Republic in Central Europe in 2007. As B. microti is the only Brucella species known to live in soil, its distribution, ecology, zoonotic potential, and genomic organization is of particular interest. The present paper is the first to report the isolation of B. microti from a wild boar ( Sus scrofa ), which is also the first isolation of this bacterial species in Hungary. Results: The B. microti isolate was cultured, after enrichment in Brucella -selective broth, from the submandibular lymph node of a female wild boar that was taken by hunters in Hungary near the Austrian border in September 2014. Histological and immunohistological examinations of the lymph node sections with B. abortus- , B. suis- and B. canis -specific sera gave negative results. The isolate did not require CO 2 for growth, was oxidase, catalase, and urease positive, H 2 S negative, grew well in the presence of 20 μ g/ml basic fuchsin and thionin, and had brownish pigmentation after three days of incubation. It gave strong positive agglutination with anti-A and anti-M but had a negative reaction with anti-R monospecific sera. The API 20 NE test identified it as Ochrobactrum anthropi with 99.9 % identity, and it showed B. microti -specific banding pattern in the Bruce- and Suis-ladder multiplex PCR systems. Whole genome re-sequencing id entified 30 SNPs in orthologous loci when compared to the B. microti reference genome available in GenBank, and the ML VA analysis yielded a unique profile. Conclusions: Given that the female wild boar did not develop any clinical disease, we hypothesize that this host species only harboured the bacterium, serving as a possible reservoir capable of maintaining and spreading this pathogen. The infectious source could have been either a rodent, a carcass that had been eaten or infection occurred via the boar rooting in soil. The low number of discovered SNPs suggests an unexpectedly high level of genetic homogeneity in this Brucella species. Keywords: Biochemistry, Brucella microti , Immunohistochemistry, MLVA, Morphology, Wild boar, Whole genome sequencing, Hungary