Dynamics of Coxiella burnetii antibodies and seroconversion in a dairy cow herd with endemic infection and excreting high numbers of the bacterium in the bulk tank milk

Possible factors related to seropositivity and seroconversion to Coxiella burnetii were examined in a dairy herd with a high Coxiella-seroprevalence and high excretion levels of the bacterium in the bulk tank milk. Antibodies were detected by using a commercial ELISA test in 50.7% of 603 parous cows. The likelihood of C. burnetii seropositivity significantly increased by factors of 1.87 and 1.61 for cows in their first and second terms of pregnancy, respectively, compared to non-pregnant cows. In 478 cows tested twice 12months apart, the seroconversion rate was 5%. The likelihood of C. burnetii-seroconversion was 2.27 times lower in multiparous than in primiparous cows and 6.88 times higher in cows during their first 90days in milk than dry-off cows. Our findings indicated a higher seroprevalence in the first and second terms of pregnancy, and that seroconversion mainly occurred in primiparous cows during their first 90days in milk.     

Extraction of antioxidants from eucalyptus (Eucalyptus globulus) bark

The extraction of phenolic compounds from eucalyptus (Eucalyptus globulus) bark was examined with the aim of analyzing the potential of the extracts as natural antioxidants. Experiments were planned according to a 2³ factorial design to analyze the influence of temperature and Na₂SO₃ and NaOH concentrations in aqueous solutions on extraction yield, extract total phenols content, ferric reducing antioxidant power (FRAP), and number- and weight-average molecular weights. Extract total phenols content and FRAP antioxidant activity in the ranges 0.91–2.58?g gallic acid equivalent (GAE)/100?g oven-dried bark and 4.70–11.96?mmol ascorbic acid equivalent (AAE)/100?g oven-dried bark, respectively, demonstrated the potential of eucalyptus bark as a source of antioxidant compounds. Extraction at the highest temperature (100°C), the lowest Na₂SO₃ concentration (1.5% on oven-dried bark), and without NaOH provided the highest extract total phenols content and FRAP antioxidant activity. Those eucalyptus bark extracts with lower molecular weight showed higher antioxidant activity. Matrix-assisted laser desorption ionization time-of-flight and reverse-phase high-performance liquid chromatography electrospray ionization time-of-flight mass spectrometry revealed the presence of polygalloyl glucoses, catechin, epicatechin, ellagic acid, quercetin-3-o-rhamnoside, and isorhamnetin in eucalyptus bark aqueous extracts.     

Comparing an individual tree growth model for <Emphasis Type="Italic">Pinus halepensis</Emphasis> Mill. in the Spanish region of Murcia with yield tables gained from the same area

To support forest management decisions on converting stands from even-aged to uneven-aged management, tree models are needed that can simulate both options. Therefore, an individual tree model for Pinus halepensis Mill. is compared with the respective yield table. The individual tree model is built from data of two Spanish forest inventories in this province and evaluated with published yield tables, which have been built from permanent observational plots. The individual tree model consists of a basal area increment model and a height increment model, both based on two measurements of about 4,000 trees from single species stands of Aleppo pine. The R2 values of 0.362 and 0.107 for the basal area increment model and the height increment model, respectively, are within the range of other published models of this type. Comparing the model with the yield tables for different site indices, we find that our model matches the yield table well. Only in higher ages where the database for the yield table was poor, our model indicates higher basal area growth rates than the yield table.     

Technology generation to dissemination: lessons learned from the tef improvement project

Indigenous crops also known as orphan crops are key contributors to food security, which is becoming increasingly vulnerable with the current trend of population growth and climate change. They have the major advantage that they fit well into the general socio-economic and ecological context of developing world agriculture. However, most indigenous crops did not benefit from the Green Revolution, which dramatically increased the yield of major crops such as wheat and rice. Here, we describe the Tef Improvement Project, which employs both conventional- and molecular-breeding techniques to improve tef—an orphan crop important to the food security in the Horn of Africa, a region of the world with recurring devastating famines. We have established an efficient pipeline to bring improved tef lines from the laboratory to the farmers of Ethiopia. Of critical importance to the long-term success of this project is the cooperation among participants in Ethiopia and Switzerland, including donors, policy makers, research institutions, and farmers. Together, European and African scientists have developed a pipeline using breeding and genomic tools to improve the orphan crop tef and bring new cultivars to the farmers in Ethiopia. We highlight a new variety, Tesfa, developed in this pipeline and possessing a novel and desirable combination of traits. Tesfa’s recent approval for release illustrates the success of the project and marks a milestone as it is the first variety (of many in the pipeline) to be released.     

Effect of Azospirillum lipoferum and Azotobacter chroococcum on germination and early growth of hopbush shrub (Dodonaea viscosa L.) under salinity stress

Reduced physiological efficiency as well as low and irregular germination rate under environmental stress conditions (e.g., salinity) are among the major factors affecting the propagation of numerous plants, in particular medicinal ones. A factorial experiment using a completely randomized design was employed to evaluate the effect of plant growth-promoting rhizobacteria (PGPR) on hopbush seed germination and seedling growth under salinity stress. After the seeds were inoculated with the Azospirillum lipoferum, Azotobacter chroococcum, and Azospirillum + Azotobacter and exposed to salinity stress at six levels, they were placed into a germinator at 20°C temperature and 65% relative humidity with a photoperiodic regime of 16 h light/8 h dark at 1,000 lux fluorescent light. The seeds inoculated with the bacterial strains could tolerate salinity levels of up to 50 dS/m and germinate. The combined treatment of Azospirillum + Azotobacter increased germination percentage at 20 and 50 dS/m levels by 21.67 and 10%, respectively. Also, A. chroococcum at 15 and 20 dS/m and Azospirillum + Azotobacter at 50 dS/m stress levels increased germination rate by 88, 316, and 155%, respectively, compared with the control. Furthermore, plant growth parameters—e.g., root and stem length, root and stem dry and fresh weights, as well as the ratios of root length and weight to the stem counterparts—were considerably enhanced by Azotobacter chroococcum treatment under elevated salinity stress (15 and 20 dS/m), relative to the control. Inoculation with A. chroococcum more favorably affected on and was also more compatible with Dodonaea viscosa seedlings leading to considerably improved seedlings growth parameters as well as seed germination under salinity stress.     

Dynamics of ecosystem services in <Emphasis Type="Italic">Pinus sylvestris</Emphasis> stands under different managements and site quality classes

Timber and biodiversity are considered two antagonistic ecosystem services (ES), largely influenced by silviculture and site ecological conditions. In order to address the trade-offs between these two ES over time, we performed a retrospective study at compartment level in the Pinus sylvestris forests of the Spanish Central Mountain System. Archival data from Management Plans for eight forests with contrasting silvicultural systems (uniform shelterwood system, group shelterwood system, irregular shelterwood system,) and three different site quality classes were analysed. Timber production was assessed through stand volume, harvested timber volume and a stand volume index. Biodiversity was examined through structural diversity (Gini index, Shannon tree size diversity index, Simpson’s reciprocal index and evenness index, all applied to diameter classes) and the abundance of large living trees. For all silvicultural systems investigated, stand volume and harvested timber volume have grown since the beginning of the management plans (beginning of the twentieth century in some forests). The largest yields of timber corresponded to the best quality sites with more intensive silvicultural treatments (uniform and group shelterwood systems). The uniform shelterwood system showed lower figures for structural diversity, though not always significant. The best site qualities maintained notable structural diversity values, even under the most intensive management system. The application of the different management systems over decades has revealed a synergy between timber production and structural diversity, particularly in those systems maintaining more than one age class, although results are conditioned by forest harvesting history. The interaction between historical silvicultural treatment and site quality has been identified as an important source of information to understand forest dynamics and functioning of ES provision.     

In Situ Aquaculture Methods for Dysidea avara (Demospongiae,Porifera) in the Northwestern Mediterranean

Marine sponges produce secondary metabolites that can be used as a natural source for the design of new drugs and cosmetics. There is, however, a supply problem with these natural substances for research and eventual commercialisation of the products. In situ sponge aquaculture is nowadays one of the most reliable methods to supply pharmaceutical companies with sufficient quantities of the target compound. In this study, we focus on the aquaculture of the sponge Dysidea avara (Schmidt, 1862), which produces avarol, a sterol with interesting pharmaceutical attributes. The soft consistency of this species makes the traditional culture method based on holding explants on ropes unsuitable. We have tested alternative culture methods for D. avara and optimized the underwater structures to hold the sponges to be used in aquaculture. Explants of this sponge were mounted on horizontal ropes, inside small cages or glued to substrates. Culture efficiency was evaluated by determination of sponge survival, growth rates, and bioactivity (as an indication of production of the target metabolite). While the cage method was the best method for explant survival, the glue method was the best one for explant growth and the rope method for bioactivity.