Herd-level prevalence of selected endemic infectious diseases of dairy cows in Great Britain

To implement appropriate and effective disease control programs at the national level, up-to-date and unbiased information on disease frequency is needed. The aim of this study was to estimate the prevalence of selected endemic infectious diseases in the population of dairy herds in Great Britain. Bulk milk tank (BMT) samples from 225 randomly selected dairy farms, stratified by region and herd size, were tested for antibodies against bovine viral diarrhea virus (BVDV), bovine herpesvirus type 1, Mycobacterium avium ssp. paratuberculosis, Leptospira Hardjo, Salmonella spp., Coxiella burnetii, Fasciola hepatica, Neospora caninum, and Ostertagia ostertagi. Furthermore, the presence of BVDV, C. burnetii, and Chlamydia-like organisms was determined by PCR. The apparent herd prevalence was estimated as a weighted proportion of positive herds. The true prevalence was calculated when a test was used with known test characteristics for the cut-off value used. Among unvaccinated herds, the true prevalence of BMT antibodies against BVDV was estimated at 66% [95% confidence interval (CI): 56–77%], M. avium ssp. paratuberculosis 68% (95% CI: 59–77%), bovine herpesvirus type 1 62% (95% CI: 52–73%), Leptospira Hardjo 47% (95% CI: 34–60%), and Salmonella spp. 48% (95% CI: 39–56%). The apparent prevalence of BMT antibodies against C. burnetii was 80% (95% CI: 75–85%), F. hepatica 55% (95% CI: 48–62%), N. caninum 46% (95% CI: 38–54%), and O. ostertagi 95% (95% CI: 91–98%). The BVDV, C. burnetii, and Chlamydia-like antigens were detected in 5 (95% CI: 2–9%), 29 (95% CI: 21–36%), and 31% (95% CI: 24–38%) of herds, respectively. Our results show that dairy cows across GB are frequently exposed to the studied pathogens, which are endemic at high levels with some geographical variations. These prevalence estimates provide a much-needed basis to assess whether nationwide control programs for the studied pathogens are justified by their potential economic, environmental, and public health implications. Should surveillance and control programs be initiated, the estimates presented here are a baseline against which progress can be assessed

Microbial diversity and community composition of caecal microbiota in commercial and indigenous Indian chickens determined using 16s rDNA amplicon sequencing

Different alpha diversity indices for each sample of university farm data estimated using QIIME for primer pair P2 data. OTUs were clustered at > 97% similarity. (XLSX 12 kb

Ohmic conduction in poly (o-toluidine)–nano CuO composite based devices

Polymer nanocomposite comprising 25 weight % of nano copper oxide (n-CuO) and poly (o-toluidine) [POT] is prepared. For the first time, we report the current–voltage (I–V) characteristics of this nanocomposite. Incorporation of n-CuO modifies the structural properties of POT. The X-ray diffraction (XRD) spectra indicate the bonding of CuO with the polymer matrix. The Band gap of the samples is estimated about 1.78 ​eV. FTIR spectra reveal presence of C–H, C–C bonds. SEM image recorded reveal substitution of n-CuO inside the POT matrix. I–V characteristic recorded at different temperature implies change in conducting behaviour of the polymer nanocomposite from conducting to semiconducting nature with change in temperature

Tuning the Non-Linear Optical Absorption Properties of Eu3+ Doped NiWO4 Nanostructures

Abstract NiWO4 nanostructures doped with different ratios of Eu3+ have been prepared by a chemical precipitation method. The influence of Eu3+ on NiWO4 nanostructures were characterized using X-ray diffraction (XRD), UV-visible diffuse reflectance spectra, scanning electron microscopy (SEM) and Raman. XRD patterns display that the samples crystallize to monoclinic wolframite structure. SEM images reveal that the particles are well uniformly dispersed with average particle size lies around 40-50nm. Third-order nonlinear optical properties were studied by a Z-scan technique at 532 nm using continuous wave diode pumped Nd:YAG laser. Open and closed aperture results reveal the nanostructures to possess reverse saturation absorption and negative nonlinear refraction. The calculated absorption coefficients (β), imaginary part of third-order susceptibilities Imχ(3) are in the order of 10-6(cm/W) and 10-7 esu. These results indicated that the synthesized nanostructures could be promising materials for optical device applications.</jats:p