Rough vaccines in animal brucellosis: structural and genetic basis and present status

Brucellosis control and eradication requires serological tests and vaccines. Effective classical vaccines (S19 in cattle and Rev 1 in small ruminants), however, induce antibodies to the O-polysaccharide of the lipopolysaccharide which may be difficult to distinguish from those resulting from infection and may thus complicate diagnosis. Rough attenuated mutants lack the O-polysaccharide and would solve this problem if eliciting protective immunity; the empirically obtained rough mutants 45/20 and RB51 have been used as vaccines. Strain 45/20 is reportedly unstable and it is not presently used. RB51 is increasingly used instead of S19 in some countries but it is rifampicin resistant and its effectiveness is controversial. Some controlled experiments have found good or absolute protection in adult cattle vaccinated orally (full dose) or subcutaneously (reduced dose) and in one field experiment, RB51 was reported to afford absolute protection to calves and to perform better than S19. Controlled experiments in calves, however, have shown reduced doses of RB51 to be ineffective, full doses only partially effective, and RB51 less effective than S19 against severe challenges. Moreover, other observations suggest that RB51 is ineffective when prevalence is high. RB51 is not useful in sheep and evidence in goats is preliminary and contradictory. Rough mutants obtained by molecular biology methods on the knowledge of the genetics and structure of Brucella lipopolysaccharide may offer alternatives. The B. abortus manBcore (rfbK) mutant seems promising in cattle, and analyses in mice suggest that mutations affecting only the O-polysaccharide result in better vaccines than those affecting both core and O-polysaccharide. Possible uses of rough vaccines also include boosting immunity by revaccination but solid evidence on its effectiveness, safety and practicality is not available.     

Application of unmanned aerial systems for high throughput phenotyping of large wheat breeding nurseries

Background

Low cost unmanned aerial systems (UAS) have great potential for rapid proximal measurements of plants in agriculture. In the context of plant breeding and genetics, current approaches for phenotyping a large number of breeding lines under field conditions require substantial investments in time, cost, and labor. For field-based high-throughput phenotyping (HTP), UAS platforms can provide high-resolution measurements for small plot research, while enabling the rapid assessment of tens-of-thousands of field plots. The objective of this study was to complete a baseline assessment of the utility of UAS in assessment field trials as commonly implemented in wheat breeding programs. We developed a semi-automated image-processing pipeline to extract plot level data from UAS imagery. The image dataset was processed using a photogrammetric pipeline based on image orientation and radiometric calibration to produce orthomosaic images. We also examined the relationships between vegetation indices (VIs) extracted from high spatial resolution multispectral imagery collected with two different UAS systems (eBee Ag carrying MultiSpec 4C camera, and IRIS+ quadcopter carrying modified NIR Canon S100) and ground truth spectral data from hand-held spectroradiometer.

Results

We found good correlation between the VIs obtained from UAS platforms and ground-truth measurements and observed high broad-sense heritability for VIs. We determined radiometric calibration methods developed for satellite imagery significantly improved the precision of VIs from the UAS. We observed VIs extracted from calibrated images of Canon S100 had a significantly higher correlation to the spectroradiometer (r = 0.76) than VIs from the MultiSpec 4C camera (r = 0.64). Their correlation to spectroradiometer readings was as high as or higher than repeated measurements with the spectroradiometer per se.

Conclusion

The approaches described here for UAS imaging and extraction of proximal sensing data enable collection of HTP measurements on the scale and with the precision needed for powerful selection tools in plant breeding. Low-cost UAS platforms have great potential for use as a selection tool in plant breeding programs. In the scope of tools development, the pipeline developed in this study can be effectively employed for other UAS and also other crops planted in breeding nurseries.

     

Influence of pH and soil copper on adsorption of metalaxyl and penconazole by the surface layer of vineyard soils

The upper horizons of old vineyard soils have substantial copper contents due to the traditional use of copper-based fungicides. Total copper levels in eight vineyard soils in the Rías Baixas area of Galicia (northwestern Spain) ranged from 60 to 560 mg kg(-1) (mean +/- SD = 206 +/- 170 mg kg(-1)). The adsorption of the fungicides metalaxyl (pK(a) = 1.41) and penconazole (pK(a) = 2.83) by these soils was determined using fungicide solutions of pH 2.5 and 5.5, and desorption of fungicide adsorbed at pH 5.5 was also determined. In all cases, Freundlich equations were fitted to the data with R (2) > 0.96. Penconazole was adsorbed and retained more strongly than metalaxyl, with K(F) values more than an order of magnitude greater. In the desorption experiments, both fungicides exhibited hysteresis. Soil copper content hardly affected the adsorption of metalaxyl, but K(F) values for adsorption of penconazole increased at a rate of about 0.1 mL(n) (microg of penconazole)(1-n) (microg of Cu)(-1), which is attributed to the formation of Cu(2+)-penconazole complexes with greater affinity for soil colloids than penconazole itself. Because the dependence of K(F) for penconazole adsorption on copper content was the same at both pH values, complex formation appears not to have been affected by the solubilization of 6-17% of soil copper at pH 2.5. A similar copper dependence, or lack of dependence, was observed when 100-1000 mg kg(-1) of copper was added as Cu(NO(3))(2).2H(2)O to the solutions from which the fungicides were adsorbed.     

Mycoplasma pneumonia of swine (MPS) resistance and immune characteristics of pig lines generated by crossing an MPS pulmonary lesion selected Landrace line and a highly immune capacity selected Large White line

To understand the influence of crossbreeding on Mycoplasma pneumonia of swine (MPS) resistance and immune characteristics, two crossbred lines were characterized. One crossbred line, LaWa, was generated by crossing the MPS pulmonary lesion selected Landrace line (La) and the highly immune‐selected Large White line (Wa). The second crossbred line, LaWb, was generated by crossing the La line and the nonselected Large White line (Wb). The crossbred LbWb line (nonselected Landrace line × nonselected Large White line) and the La line were used as controls. The LaWa and LaWb lines had an intermediate level of MPS lung lesions between La and LbWb lines, although the difference was not statistically significant. After stimulation with sheep red blood cells (SRBCs), the LaWb and LaWa lines showed immune characteristics similar to that of the La line; the number of monocytes in peripheral blood increased, while B cells, T cells, secretion of SRBC‐specific immunoglobulin G, and interleukin (IL)‐13 decreased. Additionally, the number of natural killer (NK) cells and the expression of IL‐4 and IL‐17 were significantly higher in the LaWb and LaWa lines, respectively. These data suggested that crossbreeding of La and Wa lines resulted in the inheritance of some of the selected immune responses.     

Effects of road transportation on metabolic and immunological responses in Holstein heifers

This study examined the effects of road transportation on metabolic and immunological responses in dairy heifers. Twenty Holstein heifers in early pregnancy were divided into non‐transported (NT; n = 7) and transported (T; n = 13) groups. Blood was collected before transportation (BT), immediately after transportation for 100 km (T1) and 200 km (T2), and 24 h after transportation (AT). The T heifers had higher (P < 0.05) blood cortisol and non‐esterified fatty acid concentrations after T1 and T2 than did NT heifers. By contrast, the T heifers had lower (P < 0.05) serum triglyceride concentrations after T1 and T2 than had the NT heifers. The serum cortisol and triglyceride concentrations returned (P > 0.05) to the BT concentrations at 24 h AT in the T heifers. The granulocyte‐to‐lymphocyte ratio and the percentage of monocytes were higher (P < 0.05) after T2 in the T heifers than in the NT heifers, suggesting that transportation stress increased the numbers of innate immune cells. T heifers had higher (P < 0.01) plasma haptoglobin concentrations than NT heifers 24 h AT. In conclusion, transportation increased cortisol secretion and was correlated with increased metabolic responses and up‐regulation of peripheral innate immune cells in dairy heifers.     

Ultrastructure of the tubular glands in the isthmus region of the oviduct in laying and natural moulting commercial egg‐type chickens

The study investigated the ultrastructural characteristics of tubular gland and duct cells, as well as luminal gland cells in the isthmus region of the oviduct of laying and natural moulting hens. Tubular glands in laying birds were composed of type 1 and 2 cells. Based on the preponderance of each cell type, in relation to the location of a developing egg in the oviduct of the domestic fowl, these gland cells may represent different functional states of the same cell. The findings of the study on natural moulting birds suggest that autophagy is a process confined to the early stages of degeneration, while necrosis occurs in the terminal stages.     

Effects of the dietary protein to energy ratio on growth,feed utilization and body composition in Macrobrachium nipponense

Oriental river prawn (Macrobrachium nipponense) has been widely cultured in Asian countries. However, its nutritional studies are very limited. In the present 8‐week study, we investigated the effects of dietary protein to energy ratio (P/E ratio) on the growth, feed utilization and body composition in juvenile M. nipponense (initial weight 0.302 ±0.03 g). Two‐factor experiment was designed and nine semi‐purified diets were formulated to contain three lipid levels (20, 80 and 140 g kg^?1) and three protein levels (330, 380 and 430 g kg^?1), producing P/E ratios from 16.5 to 23.4 mg KJ^?1 protein. The results indicated that the growth, survival rate and protein efficiency were dose dependently improved by the increased dietary lipid, but not dietary protein content. Increased dietary lipid content and/or protein content increased lipid accumulation in whole body, hepatopancreas and muscle, but did not change the feed intake and hepatopancreas weight. In conclusion, our present study indicated that M. nipponense is a species with relatively high‐energy requirement. It could utilize dietary lipid content up to 140 g kg^?1, while the dietary protein with more than 330 g kg^?1 would not promote growth and protein efficiency. Taken together, 330 g kg^?1 dietary protein and 140 g kg^?1 dietary lipid level with P/E ratio 16.49 could be optimum for M. nipponense.