Diversity of Bartonella species detected in arthropod vectors from animals in Australia

A variety of Bartonella species were detected in two species of ticks and three species of fleas collected from marsupial hosts; brush-tailed bettong or woylie (Bettongia penicillata) and western barred bandicoots (Perameles bougainville) and from a rodent host; Rattus fuscipes in Western Australia. Bartonella species were detected using nested-PCR of the gltA gene and the 16S–23S ribosomal internal transcribed spacer region (ITS), and species were characterized using DNA sequencing of the 16S rRNA, gltA, rpoB, ftsZ genes and the ITS region. Bartonella rattaustraliani and B. coopersplainsensis were detected in Ixodes spp. ticks and fleas (Stephanocircus pectinipes) respectively collected from rodents. Two novel Bartonella species were detected from marsupials; Candidatus Bartonella woyliei n. sp. was detected in both fleas (Pygiopsylla hilli) and ticks (Ixodes australiensis) collected from woylies and Candidatus Bartonella bandicootii n. sp. was detected in fleas (Pygiopsylla tunneyi) collected from western barred bandicoots. Concatenated phylogenetic analysis of all 5 loci clarified the marsupial cluster of Bartonella species in Australia and confirmed the species status of these two Bartonella species in ticks and fleas from woylies and western barred bandicoots, which are classified as threatened species and are vulnerable to extinction.     

Effect of Iron Status in Rats on the Absorption of Metal Ions from Plant Ferritin

An isolate of lead-ferritin obtained from soybean seeds sprouted in 25 mM of PbNO₃ was introduced into the diet of both iron-deficient and iron non-deficient male rats. After a 21-day administration period, statistical differences in the lead accumulation in the femurs of the rats were noted. Iron-deficient rats accumulated more than four times the amount of lead in their bones than rats without iron-deficiency. No further decrease was observed in haemoglobin concentrations in the groups of animals fed with lead isolates, either iron-deficient or iron non-deficient. Also, no differences in the mean corpuscular haemoglobin (MCH) and mean corpuscular volume (MCV) were observed at the end of the experiment in the group of iron non-deficient rats fed with lead-ferritin isolate compared to the control group of iron non-deficient rats. In the iron-deficient group fed with lead-ferritin isolate, a small increase in haemoglobin concentrations, MCH, MCV and mean corpuscular haemoglobin concentrations (MCHC) was recorded. The results presented in this paper confirm that lead from the tested preparation—lead ferritin isolate—was better absorbed by those rats with induced iron deficiency anaemia. Additionally, we may also suspect based on the obtained results that absorption of ferritin-iron depends on iron status in the body.     

ISApl1, a novel insertion element of Actinobacillus pleuropneumoniae, prevents ApxIV-based serological detection of serotype 7 strain AP76

Actinobacillus pleuropneumoniae, a gram-negative rod of the Pasteurellaceae family, causes pleuropneumonia in pigs. Establishing A. pleuropneumoniae free herds is difficult due to the occurrence of persistently infected animals. The ApxIV toxin is expressed by A. pleuropneumoniae in vivo and an ELISA based on the toxin is used to detect infection and to differentiate between infected and vaccinated animals. In this study, we have identified a 1070bp insertion element of the IS30 family, designated ISApl1, in the A. pleuropneumoniae serotype 7 strain AP76. ISApl1 contains a 924bp ORF encoding a transposase, which is flanked by 27bp inverted repeats showing six mismatches. We investigated the occurrence of ISApl1 in other A. pleuropneumoniae strains, and its possible interference with virulence associated factors. Four insertion sites were identified in AP76: within the apxIVA toxin ORF, within a putative autotransporter adhesin ORF, upstream of a capsular polysaccharide biosynthesis gene cluster, and downstream of a beta-lactamase gene. ISApl1 is also present in some serotype 7 field isolates, but not in reference or field strains of other serotypes. In A. pleuropneumoniae AP76, the transposase gene is transcribed in vitro. The insertion in the apxIVA toxin gene remains stable after animal passage. Since this insertion should disrupt toxin expression, we tested 7 pigs infected with AP76 at day 21 post-infection. All were negative in the ApxIV ELISA but four out of seven were positive in an ApxII toxin ELISA. These results show that insertion elements can affect the detection of A. pleuropneumoniae infected animals.     

Iron oxides as weathering indicator and the origin of Luvisols from the Vistula glaciation region in Poland

Purpose

The aim of the research was to determine the effect of lithogenic and pedogenic processes on the formation of Luvisols from the area of Vistula glaciation on the base of profile distribution of iron oxides and total iron in relation to texture and physicochemical properties. The indices of weathering of the soil material in genetic horizons were calculated, and changes in the content and forms of iron oxides were evaluated.

Materials and methods

The predominant type of soil in the study area is Luvisols under agricultural use, formed from silt formations on loam. The analyses were made applying the following methods: grain size composition using the sieve method and hydrometer method, the interpretation of the results was performed according to the World Reference Base for Soil Resources classification, the pH of soils was measured with the potentiometric method, C-organic with the Walkley-Black dichromate method, the content of the following iron forms was determined (total iron (Fe_t) after the mineralization of soils in the mixture of HF and HClO₄ acids), free iron oxides were extracted using dithionite-citrate-bicarbonate method, and amorphous iron oxides after the ammonium oxalate extraction (using the Philips 9100PU apparatus). The clay mineralogy was estimated by X-ray diffraction analysis.

Results and discussion

It was observed that total iron enrichment occurs in argic horizons accompanied by iron depletion in luvic horizons, while the profile distribution of iron is similar to the distribution of clay. The (Fe_d/Fe_t) ratio indicates a low degree of weathering; the highest values were observed in argic (Bt) horizons, which confirms the effect of the process of pedogenesis on the value of that index. In the soils investigated, crystalline iron oxides generally dominate over the amorphous forms. The mineralogical composition of clay fraction separated from the upper part of soils was different as compared to the underlying material.

Conclusions

The results of the study showed that iron contents (together with the other indicators) and its forms can be used to distinguish soil layers of different origin. The depth distribution of Fe_d, Fe_o and Fe_t within soil profiles indicates that the soil material may be of different lithogenic origin in the studied pedons.

     

Pathophysiology of the periparturient egg rise in sheep: a possible role for IgA.

The relationship between anti-parasite IgA antibody levels in plasma and the periparturient egg rise in sheep was investigated. Ostertagia circumcincta larvae (5000 third stage larvae three times weekly) were administered to three groups of seven adult immune ewes from 12 weeks before until three weeks after lambing (group 1) or from six (group 2) or 14 (group 3) weeks before until three weeks before lambing. Seven additional ewes were not challenged (group 4 controls). Ewes in groups 1, 2 and 4 received anthelmintics 14 weeks before lambing. Challenge of the pregnant ewes with O circumcincta larvae resulted in substantial increases in faecal egg counts only during the periparturient period regardless of the larval dosing regimen. Furthermore, the periparturient rise in faecal egg counts was closely associated with a significant increase in anti-parasite IgA antibody levels in plasma. This rise in IgA antibody levels occurred at a time when IgA is transported from the gut to milk during early lactation. It is postulated that this may lead to a temporary reduction in abomasal antibody levels of ewes and hence permit the establishment of larvae and, or, the emergence and development of inhibited larvae and thereby lead to the periparturient rise in faecal egg count.     

c-DNA vaccination against parasitic infections: advantages and disadvantages

Recently developed technology for DNA vaccination appears to offer the good prospect for the development of a multivalent vaccines that will effectively activate both the humoral and cell mediated mechanisms of the immune system. Currently, DNA vaccination against such important parasitic diseases like malaria, leishmaniosis, toxoplasmosis, cryptosporidiosis, schistosomosis, fasciolosis offers several new opportunities. However, the outcome of vaccination depends very much on vaccine formulations, dose and route of vaccine delivery, and the species and even strain of the vaccinated host. To overcome these problems much research is still needed, specifically focused on cloning and testing of new c-DNA sequences in the following: genome projects: different ways of delivery: design of vectors containing appropriate immunostimulatory sequences and very detailed studies on safety.     

Thrips (Thysanoptera) associated with two genetically modified types of linseed (Linum usitatissimum L.)

Journal of Plant Diseases and Protection - The aim of this study was to determine thrips abundance, species composition and seasonal dynamics on two genetically modified types of linseed, i.e.,...     

Simultaneous selection for yield-related traits and susceptibility to Fusarium head blight in spring wheat RIL population

Fusarium head blight (FHB), caused by the fungal plant pathogen Fusarium, is a fungal disease that occurs in wheat and can cause significant yield and grain quality losses. The present paper examines variation in the resistance of spring wheat lines derived from a cross between Zebra and Saar cultivars. Experiments covering 198 lines and parental cultivars were conducted in three years, in which inoculation with Fusarium culmorum was applied. Resistance levels were estimated by scoring disease symptoms on kernels. In spite of a similar reaction of parents to F. culmorum infection, significant differentiation between lines was found in all the analyzed traits. Seven molecular markers selected as linked to FHB resistance QTLs gave polymorphic products for Zebra and Saar: Xgwm566, Xgwm46, Xgwm389, Xgwm533, Xgwm156, Xwmc238, and Xgwm341. Markers Xgwm389 and Xgwm533 were associated with the rate of Fusarium-damaged kernels (FDK) as well as with kernel weight per spike and thousand kernel weight in control plants. Zebra allele of marker Xwmc238 increased kernel weight per spike and thousand kernel weight both in control and infected plants, whereas Zebra allele of marker Xgwm566 reduced the percentage of FDK and simultaneously reduced the thousand kernel weight in control and infected plants.     

Effect of light conditions on the contents of glucosinolates in germinating seeds of white mustard, red radish, white radish, and rapeseed

The study was aimed at determining the effect of light conditions on contents of glucosinolates (GLS) in germinating seeds of white mustard, red radish, white radish, and rapeseed. The seeds were germinated in light and dark, at 25 degrees C, for up to 7 days. As compared to the nongerminated seeds, in seeds exposed to light and germinated for 4, 5, 6, and 7 days the content of total GLS was observed to decrease by 30 to 70% depending on the species. Germination in conducted the dark for the respective periods of time resulted in decreases of total GLS not exceeding 25%. The changes in the concentration of total GLS were attributed to aliphatic GLS predominating in seeds, yet in the case of white mustard to sinalbin belonging to aralkyl glucosinolates. Although seeds germinated in the dark, as compared to those exposed to light, were characterized by a higher total content of indole GLS, the percentage contribution of that group of compounds in white mustard, red radish, and white radish remained at a similar level, irrespective of germination time. Only in the case of rapeseed was the percentage of the sum of indole GLS observed to increase from 17 to up to 45% once the seeds were exposed to light and to 50% once they were germinated in the dark.