ISRAEL JOURNAL OF
VETERINARY MEDICINE
SELECTIVE ABSTRACTS* OF THE 3rd ANNUAL MEETING OF THE
ISRAELI VETERINARY MICROBIOLOGY AND IMMUNOLOGY
ASSOCIATION
Chairman: D. Elad
RHODOCOCCUS EQUI INFECTION: EPIDEMIOLOGY AND
CHARACTERISTICS IN IMMUNOCOMPETENT PATIENTS
Rodoler N.
Soroka Medical Center, Beer Sheba, Israel
Background: Rhodococcus equi, previously known as Corynebacterium equi, is a
facultative intracellular gram-positive weak-acid fast coccobacillus, obligate aerobe,
which is currently classified among the nocardiform actinomycetes. It is an
established pathogen of foals and occasionally other domestic livestock (e.g. swine),
but is an uncommon cause of human infections.
R. equi is largely a soil organism with simple growth requirements that are met
perfectly by herbivore manure and summer temperatures in temperate climates. The
organism is widespread in grazing animals and their environments. R. equi is found in
the soil of 50-95% of farms, and levels are high in horse feces.
Aim: This review will focus on the epidemiology of R. equi infection in
immunocompetent patients and their possible connection to exposure to domestic
animals.
Methods: PubMed search of articles using key words, between 1967-2005.
Results: 23 case reports describing the epidemiology and the characteristics of R.equi
infection in immunocompetent patients.
Conclusion: Infection in humans is typically described in immunocompromised
patients, especially those with AIDS. On the basis of the available reports,
approximately 10-15% of infections occur in seemingly immunocompetent hosts.
Infection is acquired by inhalation from soil, inoculation into a wound or mucous
membrane, or ingestion and passage through the alimentary tract. Exposure or contact
with domesticated animals, such as horses and pigs but also dogs has been
documented in some cases of infection. Cavitary pneumonia represents the main
pathological finding of infection with R.equi, although involvement of other organs
such as the eyes, liver, brain and lymphnodes were also documented.
AUTOMATED TOTAL BACTERIAL COUNT IN RAW MILK:
ADVANTAGES AND PROBLEMS
Gips M.
Central Milk Lab, Israel Cattle Breeders' Association
Automatic evaluation of the total bacterial count of raw milk by flow cytometry (FC)
has been widely used in many countries. The bacteriological quality of milk is a
multidimensional parameter system. No single method is capable of measuring the
complete situation of the bacteriological status of a sample. The "calibration" in a
strict sense of a routine method vs. a reference method is not possible.
Notwithstanding, the Standard Plate Count method is agreed as the reference/official
method and serves as an "anchor point" when defining bacteriological quality in the
frame of legislation and trade agreements (Suhren et al. 2000). The examination of
samples reflecting the intended field of application by both methods is essential for
the elaboration of a suitable transformation of the routine values to the scale of the
reference method.
Three conversion tables from Individual Bacterial Count (IBC) to Colony Forming
Units (CFU) have been established in the Central Milk Lab, and ICBA for different
animal species (cows, sheep and goats). The conversion tables are updated all year
round in order to represent different bacterial populations in representative herds.
The main advantages of automated total bacterial count FC are the speed of analysis,
better repeatability and reproducibility of the results, the ability of detecting bacteria
which do not grow at 32 0C, and not detected by the Standard Method, and the
potential of performing surveillance of problematic farms.
Suhren, G. et al, Milchwissenschaft 55 (1) 2000
DEVELOPMENT OF ELISA FOR DETECTION OF ANTIBODIES TO
CLOSTRIDIUM BOTULINUM TOXINS AND APPLICATION IN A
SEROEPIDEMIOLOGICAL SURVEY IN FREE-LIVING WILD CANIDS IN
ISRAEL
1Millet N., 1Steinman A., 2King R., and 1Shpigel N. Y.
1. Koret School of Veterinary Medicine, Faculty of Agricultural, Food and
Environmental Sciences, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot
76100, Israel
2. Israel Nature and Parks Authority, 3 Am Ve'Olamo St., Jerusalem 95463, Israel
Botulism, a highly fatal neuroparalytic disease, caused by the toxins produced by the
bacterium Clostridium botulinum. We suspect that C. botulinum types C and D are
parasites of the gastrointestinal system of various small mammals, birds and reptiles.
These species are probably the source of carrion botulism when incorporated into
cattle feed. Wild canids preying on these animals or consuming carrion might be
exposed to these botulinum toxins. Determination of the seroprevalence of antibotulinum antibodies in these animals, which are highly resistant to the toxin, might
help us to understand the ecology of C. botulinum in this area.
Using an ELISA assay, the seroprevalence of anti-botulinum type C or D antibodies
was 29.5% in 254 free ranging wild canids captured in 2000-2004. A smaller subsample of 35 golden jackals (Canis aureus), 8 wolves (Canis lupus) and 4 red foxes
(Vulpes vulpes) was assayed with types C and D specific assays. Ten jackals (29%)
had anti-BoNT type C antibodies, and 3 (9%) also had anti-BoNT type D antibodies.
This preliminary serological survey has shown that the prevalence of anti-botulinum
type C antibodies in jackals is fairly high, suggesting that individual wild canids are
occasionally exposed to botulinum neurotoxins. The results of this study
demonstrated that this pathogen is prevalent in the wildlife population in Israel. In
face of the increasing incidence of cattle botulism in recent years, further
investigation of the ecology of C. botulinum in wildlife species is warranted.
INDUCIBLE NITRIC OXIDE IN MYCOBACTERIUM
PARATUBERCULOSIS INFECTED MACROPHAGES
1Golan L., 1,2Livneh A., 2Rosenshine I., 3Zinniel D.K., 3Chahal H.K., 3Chacon O.,
3Barletta R.G. and N.Y. Shpigel1
1.The Koret School of Veterinary Medicine, Faculty of Agriculture,2.Faculty of
Medicine, The Hebrew University of Jerusalem, 3.Veterinary and Biomedical
Sciences, University of Nebraska-Lincoln, USA
Johne’s disease (JD) is a chronic granulomatous ileitis in ruminants caused by
Mycobacterium paratuberculosis (MAP). Effective therapeutics or vaccines are not
available due to our lack of understanding of the virulence mechanisms of this
organism and the pathogenesis of the disease. Previous studies of other pathogenic
mycobacteria demonstrated the importance of the macrophage inducible nitric oxide
(NO) system in the pathogenesis of diseases like tuberculosis and leprosy. NO has
strong bacteriocidal effects against some mycobacteria and immunoregulatory effects,
affecting granuloma formation and immune response against these pathogens. The
aim of this study was to investigate the possible role of the NO system in
paratuberculosis. We have looked at the response of the NO system in various
primary and cell line macrophages elicited by different MAP strains and mutants. We
have found that MAP organisms induce the expression of the inducible nitric oxide
synthetase (iNOS) gene eliciting high levels of NO production by macrophages.
Inhibition of phagocytosis of the organisms did not alter these effects and we have
showed that soluble factors secreted by the organism induce the effects. However,
specific inhibition of iNOS in macrophages had no effect on the survival of MAP in
these cells. Considerable differences were observed between MAP strains and
mutants with respect to iNOS induction and NO production. These differences might
be associated with differences in virulence and disease processes.