Detection of Bartonella spp. in wild rodents in Israel using HRM real-time PCR

The prevalence of Bartonella spp. in wild rodents was studied in 19 geographical locations in Israel. One hundred and twelve rodents belonging to five species (Mus musculus, Rattus rattus, Microtus socialis, Acomys cahirinus and Apodemus sylvaticus) were included in the survey. In addition, 156 ectoparasites were collected from the rodents. Spleen sample from each rodent and the ectoparasites were examined for the presence of Bartonella DNA using high resolution melt (HRM) real-time PCR. The method was designed for the simultaneous detection and differentiation of eight Bartonella spp. according to the nucleotide variation in each of two gene fragments (rpoB and gltA) and the 16S–23S intergenic spacer (ITS) locus, using the same PCR protocol which allowed the simultaneous amplification of the three different loci. Bartonella DNA was detected in spleen samples of 19 out of 79 (24%) black rats (R. rattus) and in 1 of 4 (25%) Cairo spiny mice (A. cahirinus). In addition, 15 of 34 (44%) flea pools harbored Bartonella DNA. Only rat flea (Xenopsyla cheopis) pools collected from black rats (R. rattus) were positive for Bartonella DNA. The Bartonella sp. detected in spleen samples from black rats (R. rattus) was closely related to both B. tribocorum and B. elizabethae. The species detected in the Cairo spiny mouse (A. cahirinus) spleen sample was closely related to the zoonotic pathogen, B. elizabethae. These results indicate that Bartonella species are highly prevalent in suburban rodent populations and their ectoparasites in Israel. Further investigation of the prevalence and zoonotic potential of the Bartonella species detected in the black rats and the Cairo spiny mouse is warranted.     

Newly emerged nulliparous Culicoides imicola Kieffer (Diptera: Ceratopogonidae) with pigmented abdomen

The method of segregating nulliparous and parous females of Culicoides spp. based on the presence of burgundy-red pigment inside the abdominal wall of parous Culicoides midges, is used worldwide. Out of 320 females of Culicoides imicola trapped by emergence traps, set over an artificial breeding site for 10 and 24 days, 73 (22.8%) showed a red-pigmentation despite the fact that they were nulliparous. This finding indicated that 23% of the “parous” females that are examined for the presence of arboviruses and other pathogens or for age-grading purposes, are actually old nulliparous females, which had no chance of acquiring pathogens. This bias in parous rate distorts upward the calculation of vectorial capacity.     

Electrophysiological characteristic of the ventromedial hypothalamic nucleus and lateral hypothalamic area in normally fed and 24 hour food deprived conscious sheep

We registered telemetrically the spontaneous electrical activity of the hypothalamic ventromedial nucleus (VMH) and the lateral hypothalamic area (LH) in conscious adult sheep-male, with implanted electrodes,-in a state of normal feeding or after 24 hour food deprivation. The frequency of electrical activity, the amplitude of electrical activity and the frequency by Fourier analysis were evaluated. The frequency of electrical activity was found to be approximately the same in the VMH and LH with mean values +/- S.E.M. 11.5 +/- 0.5 Hz in feed sheep. The amplitude of electrical activity in the VMH was higher compared with the LH, with mean absolute values +/- S.E.M. 41.5 +/- 2.7 microV in the VMH and 35.5 +/- 3.2 microV in the LH. The Fourier analysis showed that from the total amount of harmonic frequencies-the first one i.e. the basic frequency represented 48-56%, the rest are higher frequencies. In sheep after 24 hour food deprivation the frequency of electrical activity decreased on 9.4-9.6 Hz in average in both regions under study and the absolute values of the amplitude of electrical activity increased. The mean absolute value +/- S.E.M. was 115 +/- 5.2 microV in the VMH and 101.2 +/- 3.0 microV in the LH. Along with theses changes we found by Fourier analysis that in the total amount of harmonic frequencies the basic frequency decreased by 6% due to the greater amount of higher harmonic frequencies.