Ultrasound-guided thoracic paravertebral injection in dogs: a cadaveric study

Objective

To describe ultrasound-visualized anatomy and the spread characteristics of a dye injected in the thoracic paravertebral (TPV) space under ultrasound guidance.

A multi-criteria approach to identify favorable areas for goat production systems in Veracruz,México

This research identifies favorable areas for goat production systems in the state of Veracruz, Mexico. Through the use of the analytic hierarchy process, layers of biophysical and soil information were combined to generate a model of favorability. Model validation was performed by calculating the area under the curve, the true skill statistic, and a qualitative comparison with census records. The results showed the existence of regions with high (4494.3 km²) and moderate (2985.8 km²) favorability, and these areas correspond to 6.25 and 4.15%, respectively, of the state territory and are located in the regions of Sierra de Huayacocotla, Perote, and Orizaba. These regions are characterized as mountainous and having predominantly temperate-wet or cold climates, and having montane mesophilic forests, containing pine, fir, and desert scrub. The reliability of the distribution model was supported by the area under the curve value (0.96), the true skill statistic (0.86), and consistency with census records.     

Host-suitability of black medick (<Emphasis Type="Italic">Medicago lupulina</Emphasis> L.) and additional molecular markers for identification of the pea cyst nematode <Emphasis Type="Italic">Heterodera goettingiana</Emphasis>

A survey was conducted in 16 fields cultivated with broad bean (Vicia faba L.) and garden pea (Pisum sativum L.) in nine localities of Apulia, southern Italy, to determine whether annual weeds were susceptible to the pea cyst nematode (PEACN), Heterodera goettingiana, and could therefore serve as alternate host for the nematode. The results of this study showed that black medick (Medicago lupulina L.) is a good host for the nematode increasing its population levels in the soil in the absence of the primary hosts. The identity of the PEACN was confirmed by integrative taxonomic approaches (classical, and molecular), resulting identical in all cases (broad bean and garden pea, as well as the spontaneous black medick infections). The phylogenetic analyses using ITS and coxI gene regions strongly support the identification of the populations of H. goettingiana from Italy. Also, ITS and coxI gene sequences were obtained from the same cyst, confirming the species identity in comparison to other nematodes and populations in the Goettingiana group, demonstrating that ITS and coxI gene regions of the PEACN are suitable molecular markers for accurate and unequivocal identification of the PEACN. Reproduction and histopathological analyses demonstrated a good host-suitability of black medick to the PEACN. This record enlarges the relatively narrow host-range of the pea cyst nematode and indicates the need to control M. lupulina to avoid the increase of the nematode population in the absence of the main host crop.     

Secondary Nothofagus dombeyi forests: site index curves and dominant height in the Coastal Range of south-central Chile

Nothofagus dombeyi is distributed on very diverse sites in the temperate forests of Chile and Argentina. In Chile, studies on its dynamics and productivity in forests, where it is the dominant species, have been carried out mainly in the foothills of the Andes, but the productivity and growth of these forests in the Coastal Range are almost unknown. The objective of this study was to evaluate the construction of a single dominant height/age growth model for two homogeneous edaphoclimatic zones (ZEH 2 and 5) previously defined for this species in the Coastal Range of south­central Chile. The results showed that the Chapman-Richards model was the best candidate function, in terms of goodness of fit and predictive capabilities. Using this function, specific parameters (a, b and c) were obtained for each zone, from which site models were constructed by the Algebraic Difference Approach method for a base age of 35 years. This model is intended to contribute to better estimations of site productivity for N. dombeyi forests in the Coastal Range of south-central Chile, and thus facilitate private and public decisions regarding their management.     

The relative importance of soil properties and regional climate as drivers of productivity in southern Patagonia’s <Emphasis Type="Italic">Nothofagus antarctica</Emphasis> forests

Key message

Soil texture and temperature-related variables were the variables that most contributed to Nothofagus antarctica forest height in southern Patagonia. This information may be useful for improving forest management, for instance related to the establishment of silvopastoral systems or selection of suitable sites for forest reforestation in southern Patagonia.

Context

Changes in forest productivity result from a combination of climate, topography, and soil properties.

Aims

The relative importance of edaphic and climatic variables as drivers of productivity in Nothofagus antarctica forests of southern Patagonia, Argentina, was evaluated.

Methods

A total of 48 mature stands of N. antarctica were selected. For each study site, we measured the height of three mature dominant trees, as an indicator of productivity. Seven soil, five spatial, and 19 climatic features were determined and related to forest productivity. Through partial least squares regression analyses, we obtained a model that was an effective predictor of height of mature dominant trees in the regional data set presented here.

Results

The four variables that most contributed to the predictive power of the model were altitude, temperature annual range, soil texture, and temperature seasonality.

Conclusion

The information gathered in this study suggested that the incidence of the soil and temperature-related variables on the height of dominant trees, at the regionally evaluated scale, was higher than the effect of water-related variables.

     

Home garden agrobiodiversity in cultural landscapes in the tropical lowlands of Tabasco,México

We studied whether agrobiodiversity in home gardens reflects the cultural landscapes that embed them. We compared floristic composition, biomass and cover of trees in home gardens between the cultural landscapes on mountain slopes (MSL), small hills (SHL), and floodplains (FPL) in a segment of the Grijalva–Usumacinta watershed in the tropical lowlands of Tabasco, Mexico. We characterized the cultural landscapes based on information obtained through questionnaires, identified species and measured tree height and diameter at breast height in random samples of home gardens from two localities in each case. The cultural landscapes showed distinct land use combinations: MSL comprised subsistence agriculture, pasturelands and forests; SHL pasturelands, some secondary vegetation and industrial agriculture fields; and FPL mainly industrial agriculture fields and pasturelands. Total species richness was greater in MSL than in SHL and FPL. Mean species richness was greater in MSL and SHL (22.4 and 15.8 respectively) than in FPL (7.2), as was the mean number of individuals per home garden (98.2, 94.1 and 20.4. Dominant species in home gardens in FPL and SHL included particular secondary species for each landscape, whereas single or double occurrences of mature forest species were distinctive of home gardens in MSL. Mean biomass was greater in MSL than in SHL and FPL (37.1, 28.2 and 23.7 Mg C ha^?1), as was tree cover (1.06, 0.95 and 0.76 m²/m²). We conclude that agrobiodiversity varies considerably among cultural landscapes and recommend the design of specific policies to enhance its conservation in each of them.     

Tree Quality in Agroforestry Systems Managed by Small-Scale Mayan Farmers in Chiapas,Mexico

Increasingly, plantations for food, fiber and wood, are necessary to provide a growing world population. Agroforestry systems become more and more important, however these systems usually develop in marginal conditions, limited land, restricted funding, occasional technical support and above this, there is limited documentation and evaluation of innovated traditional systems in indigenous and small-scale contexts, which challenge forest scientists. The aim of this research was to assess the quality of trees in plots managed by Mayan indigenous farmers who planted agroforestry systems with fine wood species to increase the value of land and labor in localities with highly-marginal social conditions in Northern Chiapas, México. Twenty oldest plots were selected within a group of previously established plots (eight with improved fallow, six with shaded coffee and six with maize crop associated to trees) where forest inventories were carried out in nested 100 and 1000 m²-circular plots. In all plots tree diameter, height, quality indicators and the incidence of the pest Hypsipyla grandella were measured. Trees in the maize-associated-to-trees system are favored by the practices applied to annual crop during the first 3rd–5th years, a period in which they are free from the interference of other trees and benefit from favorable light conditions, weeding and a higher intensive care from the farmer while shaded coffee and improved fallow have higher tree densities and a more closed canopy condition than maize associated to trees. In consequence, maize associated to trees shows 68.1 % stems with good form; shaded coffee and improved fallow averaged 40.5 and 39.7 % of good quality stems, respectively; improved fallow exhibited a greater number of suppressed trees than shaded coffee and maize associated to trees (p < 0.0001). In addition, maize associated to trees showed the highest proportion of trees with commercial value with 56.9 %, followed by improved fallow with 28.2 %, and shaded coffee with 11.8 % (p < 0.0001); the rest were trees with domestic uses. However, maize associated to trees significantly result with high incidence of H. grandella probably due to the crown exposure. Timber volume averaged 92.9 ± 68.9 m³ for improved fallow, 77.3 ± 24.8 m³ for shaded coffee, and 52.5 ± 39.7 m³ for maize associated to trees. The value of the fine wood represents increment in income, variety of products and self-employment for households. Nonetheless, improved fallow and coffee plantations might benefit from the elimination of competitors from larger trees to favor promising immature ones and pruning, while maize crop associated to trees might benefit from opportune pruning for controlling the stem borer as well as tree replacement to achieve long term replacement and harvesting.     

Silvopastoral systems improve carbon stocks at livestock ranches in Tabasco,Mexico

Silvopastoral systems have great potential for storing carbon because of carbon assimilation in tree woody biomass, carbon input through litterfall and below-ground carbon turnover. In this study, we quantified and compared the carbon stocks at livestock ranches in Tabasco, Mexico, containing either scattered trees in grazing pastures (STP) or grass monocultures. Sampling plots were randomly established at each ranch where the above- and below-ground carbon stocks, carbon input from litterfall, grass production and arboreal biomass growth were measured. We found that silvopastoral systems stored an average of 257.45 Mg ha⁻¹ of soil organic carbon (SOC) compared to 119.17 Mg SOC ha⁻¹ at grass monoculture ranches (to 30 cm depth); silvopastoral systems also stored 44.64 Mg C ha⁻¹ in wood biomass; and, grass monocultures had greater cumulative grass biomass production. Overall, it is concluded that livestock ranches in Tabasco, Mexico, with scattered trees in grazing pastures stored 58.8% more carbon than those grass monocultures, with carbon stocks of 327.01 Mg C ha⁻¹and 134.47 Mg C ha⁻¹, respectively. The results are useful for land management decision making for sustainable livestock systems framed in the Sustainable Development Goals (SDGs).     

Effects of Yeast Freezing in Frozen Dough

The effects of freezing and frozen storage of bread dough and compressed yeast on bread quality were studied. Besides, the effects of compressed yeast freezing on cell viability, gas production and release of substances by the yeast cells were examined. Freezing and frozen storage of dough made with fresh yeast had more negative effects on baking quality than the addition of frozen yeast to dough. When the compressed yeast is frozen and stored at ‐18°C, the CO₂ production decreased, while the amount of dead cells, the total protein, and the total reducing substances leached from the yeast increased as the length of yeast frozen storage increased. SDS‐PAGE showed that the substances leached from frozen yeast caused an increase in the solubility of some gluten proteins. On the other hand, size‐exclusion chromatography (SEC) pointed out that the relative amount of two protein fractions of low molecular weight leached from frozen yeast increased for longer yeast frozen storage periods. The yeast leachates had an adverse effect on loaf volume.