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The standard procedure for the improved cultural recovery of viable Mycobacterium spp. from diverse samples mainly depends on reducing the viability of background microbiota using different chemical compounds. This study was designed to i) evaluate the efficacy and comparison between N-Acetyl-l-Cysteine-Sodium hydroxide (NALC-2% NaOH) and hexadecylpyridinium chloride (0.75% HPC) treatment and exposure time on reducing the viability of undesirable microorganisms with minimal impact on colostrum consistency; and ii) assess the impact of NALC-2% NaOH on improved and enhanced recovery of Mycobacterium avium subsp. paratuberculosis (MAP) in spiked postpartum colostrum samples and consistency of colostrum. A total of 40 samples, each treated with NALC-2% NaOH for 15 min or 0.75% HPC for 5 h, were investigated for total mesophilic aerobic bacteria (MAB) and enterobacteria (EB) (CFU mL-1). The results showed that treatment of colostrum samples with NALC-2% NaOH completely eliminated EB and significantly reduced MAB (3.6 log10 CFU mL-1). Conversely, samples treated with 0.75% HPC produced a complex mixture following interaction with the colostrum protein and showed non-significant and variable results. In addition, the spiked colostrum treated with NALC-2% NaOH for 15 min revealed recovery of viable MAP cells with a minimum limit of detection of 1.36 log10 CFU 10 mL-1 where no change in the consistency of colostrum was observed. In conclusion, 15-min NALC-2% NaOH treatment of colostrum may significantly reduce the viability of undesirable microorganisms and help to enhance the efficient recovery of MAP without impacting the consistency of high quality postpartum colostrum. This rapid procedure is suitable for efficient recovery and early detection of MAP as well as preventing its transmission to neonates and young calves in MAP infected herds.

The present study was designed to identify nine Arcanobacterium phocae strains isolated from cases of mink dermatitis of a single farm in Finland and characterize the strains for epidemiological relationships. All nine strains and previously described A. phocae used for comparative purposes were identified and further characterized phenotypically, by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), by Fourier Transform Infrared Spectroscopy (FT-IR) and genotypically by detection of phocaelysin encoding gene phl with a previously developed loop-mediated isothermal amplification (LAMP) assay and by sequencing 16S rRNA gene and gene phl, the elongation factor tu encoding gene tuf and the β subunit of bacterial RNA polymerase encoding gene rpoB. Genetic relatedness among isolates was determined using whole-genome single nucleotide polymorphism (wgSNP) analysis. The wgSNP results, partly the MALDI-TOF MS and FT-IR analyses and sequencing of the genes, revealed that the nine A. phocae strains recovered from a single farm showed close sequence similarities among each other and differed from previously investigated A. phocae strains isolated from other farms and animals in Finland and from the A. phocae type strain. This indicated a close epidemiological relationship of the A. phocae strains isolated from a single farm and that the nine A. phocae strains of the present study might have developed from a common ancestor.

The correlation between Johne's disease (JD) and Crohn's disease (CD) in Egypt was investi- gated. A total of 371 human and 435 animal sera were collected from the same Egyptian governorates that had a known history of paratuberculosis infection and were subjected to screening for paratuberculosis using ELISA to assess the human/animal risk at a single time point. Five CD patients and five JD clinically infected dairy cattle were also included. Out of 435 animal serum samples, 196 (45.2%) were MAP-ELISA positive. Twenty three (6.1%) out of 371 human serum samples were MAP-ELISA positive, while 37 (9.9%) were positive for anti-Saccharomyces cerevisiae antibodies (ASCA) ELISAs. There was a very poor agreement between human MAP and ASCA ELISAs (0.036 by kappa statistics). The prevalence of MAP antibodies among humans is clearly lower than in animals. In conclusion there is an increase in Johne's disease incidence in animals and a very weak relationship between MAP and Crohn's disease in humans in Egypt. a 2013 Production and hosting by Elsevier B.V. on behalf of Faculty of Veterinary Medicine, Cairo University.

In the present work a total of 143 Mycobacterium avium subsp. paratuberculosis (Map) field isolates recovered from faeces of dairy cattle in Hessen State, Germany were investigated. Different Short Sequence Repeats (SSR), Mycobacterial Interspersed Repetitive Units (MIRU) and Variable Number Tandem Repeats (VNTR) were applied to classify these cattle-group field isolates into subgroups. When combining the results obtained from SSR sequencing together with the data obtained from other genotyping PCR techniques applied in the current study, 78 different Map profiles were detected. One profile dominates over the investigated field isolates. This profile was detected in 24 isolates (16.8%) with 11 G (SSR); amplicon size of 280 bp, 300 bp, 200 bp, 200 bp, 210 bp, 350 bp, 210 bp, 300 bp and 300 bp for the primer MIRU 2, MIRU 3, X3, Primer 3, Primer 7, Primer 25, Primer 47, 292 and VNTR 1658, respectively. One profile was represented by eight isolates. Two profiles were represented by six members each. The remaining isolates were subdivided into smaller groups (2 profiles each 4 isolates, 3 profiles each 3 isolates, 13 profiles as 2 isolates each and finally 56 profiles were represented by a single strain for each profile).

In the present study a Trueperella (Arcanobacterium) bernardiae strain isolated from an anal swab of a three-day-old piglet could be identified phenotypically, by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and genotypically by sequencing the 16S rDNA, the 16S-23S rDNA intergenic spacer region (ISR) and by sequencing the superoxide dismutase A encoding gene sodA. The present study gives the first information about the presence of T. (A.) bernardiae in specimen of animals.

A species specific PCR test, based on manganese-dependent superoxide dismutase A encoding gene sodA, was developed for the identification of Staphylococcus hyicus, an important bacterial pathogen in pigs. The designed primers allowed a rapid and reliable identification of phenotypically characterized S. hyicus, isolated in Russia, Germany and Denmark. No cross reactivities could be observed investigating staphylococcal reference strains representing 18 different species and subspecies. The use of the described primers might improve a future diagnosis of this bacterial pathogen.

Species-specific PCR tests, based on the manganese-dependent superoxide dismutase A encoding gene (sodA) and the chaperonin 60 encoding gene (cpn60), were developed for the identification of Streptococcus phocae, a bacterial pathogen of seals. The selection of both oligonucleotide primer pairs was performed after amplification and sequencing of internal parts of both genes using universal oligonucleotide primers. The sequence studies of both genes additionally confirmed that S. phocae could taxonomically be classified to the pyogenic group of the genus Streptococcus.

Summary The 16S–23S rDNA intergenic spacer regions (ISR) of different streptococcal species and subspecies were amplified with primers derived from the highly conserved flanking regions of the 16S rRNA and 23S rRNA genes. The single sized amplicons showed a uniform pattern for S. agalactiae , S. dysgalactiae subsp. dysgalactiae (serogroup C), S. dysgalactiae subsp. equisimilis (serogroup G), S. dysgalactiae subsp. dysgalactiae (serogroup L), S. canis , S. phocae , S. uberis , S. parauberis , S. pyogenes and S. equi subsp. equi , respectively. The amplicons of S. equi subsp. zooepidemicus , S. porcinus and S. suis appeared with 3, 5 and 3 different sizes, respectively. ISR of selected strains of each species or subspecies investigated were sequenced and multiple aligned. This allowed a separation of ISR into regions, with 7 regions for S. agalactiae , S. dysgalactiae subsp. dysgalactiae (serogroup C), S. dysgalactiae subsp. equisimilis (serogroup G), S. dysgalactiae subsp. dysgalactiae (serogroup L), S. canis , S. phocae , S. pyogenes and S. suis , 8 regions for S. uberis and S. parauberis and mostly 9 regions for S. equi subsp. equi , S. equi subsp. zooepidemicus and S. porcinus. Region 4, encoding the transfer RNA for alanine (tRNA Ala ), was present and identical for all isolates investigated. The size and sequence of ISR appears to be a unique marker for streptococci of various species and subspecies and could be used for bacterial identification. In addition the size and sequence variations of ISR of S. equi subsp. zooepidemicus , S. porcinus and S.suis allows a molecular typing of isolates of these species possibly useful in epidemiological aspects.

A total of 57 bacteria representing eight species of genus Arcanobacterium (A.) were investigated for hemolytic properties on blood agar containing sheep and rabbit blood and for CAMP-like reactions. An enhanced hemolysis on blood agar containing rabbit blood compared to sheep blood could be observed for A. haemolyticum, less pronounced for A. hippocoleae and A. pluranimalium. A synergistic hemolytic reaction with staphylococcal beta-hemolysin appeared to be constantly visible for A. hippocoleae, A. pluranimalium and A. pyogenes, with Streptococcus agalactiae for A. phocae and A. haemolyticum, with Rhodococcus equi for A. phocae, A. haemolyticum, A. pluranimalium and A. pyogenes and with A. haemolyticum for A. hippocoleae, A. pluranimalium and A. pyogenes, respectively. A reverse CAMP-reaction in the zone of staphylococcal beta-hemolysin could be observed for A.phocae and A.haemolyticum. In addition, a novel CAMP-like reaction could be noted between Psychrobacter phenylpyruvicus, identified by 16S rDNA sequencing, and A. phocae and A. haemolyticum. These synergistic or antagonistic hemolytic properties could possibly be used as additional criteria for identification of bacteria of genus Arcanobacterium.