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1.
Polymers (Basel) ; 14(20)2022 Oct 15.
Article in English | MEDLINE | ID: mdl-36297926

ABSTRACT

The effect of four lignocellulosic waste fillers on the thermal and mechanical properties of biocomposites was investigated. Powdered licorice root, palm leaf, holm oak and willow fillers were melt compounded with polypropylene at two different weight contents, i.e., 10 and 30, and then injection molded. A commercially available maleated coupling agent was used to improve the filler/matrix interfacial adhesion at 5 wt.%. Composites were subjected to chemical (FTIR-ATR), thermal (TGA, DSC, DMA) and mechanical (tensile, bending and Charpy impact) analyses coupled with a morphological investigation by scanning electron microscopy. Although similarities among the different formulations were noted, holm oak fillers provided the best combination of thermal and mechanical performance. In particular, at 30 wt.% content with coupling agent, this composite formulation displayed remarkable increases in tensile strength and modulus, flexural strength and modulus, of 28% and 110%, 58% and 111%, compared to neat PP, respectively. The results imply that all these lignocellulosic waste fillers can be used successfully as raw materials for biocomposites, with properties comparable to those featured by other natural fillers.

2.
Animals (Basel) ; 11(6)2021 May 29.
Article in English | MEDLINE | ID: mdl-34072485

ABSTRACT

The analysis of body shape variability has always been a central element in biology. More recently, geometric morphometry has developed as a new field in shape analysis, with the aim to study body morphological variations and the identification of their causes. In wildlife management, geometric morphometry could be a useful tool to compare the anatomical structures of an organism and quantify its geometric information in order to relate them to environmental factors, thus identifying the causes and effects of the variation and acting management and/or conservation plans. The aim of our study is to evaluate the relationship between roe deer mandible shape and trophic resources available during autumn and winter. We applied a geometric morphometry approach consisting of a Relative Warp analysis of landmark data in 26 roe deer fawn mandibles. Each sample was assigned to an age category and to an environmental category based on the territory carrying capacity. The mandible shape of samples under 8 months of age is likely influenced by the availability of trophic resources. Our findings suggest that the mandible shape is a reliable instrument to assess resource availability. Geometric morphometry could thus represent an additional tool for roe deer management.

3.
Int J Food Sci Nutr ; 71(1): 50-62, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31163113

ABSTRACT

The effect of feeding supplementation on the nutritional characteristics of milk and cheese was studied in dairy sheep grazing on low mountain dry-grasslands during summer in typical sub-Mediterranean conditions of aridity. The control group (CG) of 25 sheep grazed on grass, while the experimental group (EG) of 25 sheep grazed on grass and received 600 g a day of a barley and corn mixture. Daily milk production showed a less pronounced decrease in EG than in CG (p ˂ 0.0368). After one month of supplementation, the concentrations of retinol and α-tocopherol in milk and cheese from EG were higher than CG (p < 0.05). Supplementary feeding had a positive effect on the fatty acid composition of the sheep milk. For the first time, positive effects on the volatile composition were found in EG cheese, displaying lower percentages of carboxylic acids associated with the pungent and rancid odour with respect to CG.


Subject(s)
Animal Feed , Cheese/analysis , Diet/veterinary , Dietary Supplements , Milk/chemistry , Nutritive Value , Animal Nutritional Physiological Phenomena , Animals , Fatty Acids/analysis , Female , Italy , Poaceae , Seasons , Sheep , Tocopherols , Vitamin A , Volatile Organic Compounds/analysis , Zea mays
4.
Sci Rep ; 7(1): 12034, 2017 09 20.
Article in English | MEDLINE | ID: mdl-28931871

ABSTRACT

Timing of flowering is a critical component of community assembly, but how plant traits respond to heterogeneity of resources has been identified mostly through observations of spatial variations. Thus, we performed a trait-based phenological study in sub-Mediterranean grasslands to assess the importance of temporal variation of resources in the species assemblage processes. We found that early flowering species have traits allowing for slow resource acquisition and storage but rapid growth rate. Instead, mid- and late-flowering species exhibited sets of strategies devoted to minimizing water loss by evapotranspiration or aimed at maximizing the species' competitive ability, thanks to slow growth rate and more efficient resource acquisition, conservation and use. Our findings were consistent with the fluctuation niche theory. We observed that the amplitude of the environmental fluctuations influences the type and number of strategies positively filtered by the system. In fact, in the most productive grasslands, we observed the highest number of indicator trait states reflecting strategies devoted to the storage of resources and competition for light. Results seem also indicate that temporal variation of resources plays a role in trait differentiation and richness within a plant community, filtering traits composition of grasslands in the same direction, as formerly proved for spatial heterogeneity of resources.

5.
PLoS One ; 11(11): e0167265, 2016.
Article in English | MEDLINE | ID: mdl-27902757

ABSTRACT

Facilitation processes constitute basic elements of vegetation dynamics in harsh systems. Recent studies in tropical alpine environments demonstrated how pioneer plant species defined as "ecosystem engineers" are capable of enhancing landscape-level richness by adding new species to the community through the modification of microhabitats, and also provided hints about the alternation of different ecosystem engineers over time. Nevertheless, most of the existing works analysed different ecosystem engineers separately, without considering the interaction of different ecosystem engineers. Focusing on the altitudinal limit of Peruvian Dry Puna vegetation, we hypothesized that positive interactions structure plant communities by facilitation cascades involving different ecosystem engineers, determining the evolution of the microhabitat patches in terms of abiotic resources and beneficiary species hosted. To analyze successional mechanisms, we used a "space-for-time" substitution to account for changes over time, and analyzed data on soil texture, composition, and temperature, facilitated species and their interaction with nurse species, and surface area of engineered patches by means of chemical analyses, indicator species analysis, and rarefaction curves. A successional process, resulting from the dynamic interaction of different ecosystem engineers, which determined a progressive amelioration of soil conditions (e.g. nitrogen and organic matter content, and temperature), was the main driver of species assemblage at the community scale, enhancing species richness. Cushion plants act as pioneers, by starting the successional processes that continue with shrubs and tussocks. Tussock grasses have sometimes been found to be capable of creating microhabitat patches independently. The dynamics of species assemblage seem to follow the nested assemblage mechanism, in which the first foundation species to colonize a habitat provides a novel substrate for colonization by other foundation species through a facilitation cascade process.


Subject(s)
Altitude , Ecosystem , Poaceae , Biodiversity , Biological Evolution , Poaceae/classification , Poaceae/growth & development , Soil
6.
Microsc Res Tech ; 79(8): 738-43, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27271434

ABSTRACT

The aim of this study was to investigate how the Surface Enlargement Factor (SEF) and the epithelial keratinization degree of sheep rumen change in response to phytomass production, and to forage fiber and water content during the pasture vegetative cycle. The study used eighteen sheep nourished with dry hay and cereals during the winter season and with fresh hay during the pasture vegetative cycle. We collected samples from rumen indicative regions for two consecutive years characterized by different rainfall and pasture productivity values. We evaluated the densities (D) of rumen papillae to estimate the rumen SEF, and the keratinization percentage of the epithelial lining; these parameters showed differentiated modifications in the four ruminal analyzed compartments in response to pasture seasonal conditions. In addition, we performed Canonical Redundancy Analysis (RDA) on the "keratinization and SEF" matrix constrained by phytomass, water, and crude fiber contents of pasture at different time in the two considered years to highlight how rumen features answer to pasture conditions. Atrium (A) and ventral sac (VS) keratinization showed a strict positive correlation to crude fiber, while SEF of VS was positively related to phytomass and forage water content. The degree of keratinization of the rumen VS epithelium proved to be a useful parameter for evaluating anatomical variations in the short term period related to pasture features; in addition, its monitoring could be carried out through biopsy, thus avoiding the killing of animals. The study also leads to the application of the 3Rs (Replacement; Reduction; and Refinement). Microsc. Res. Tech. 79:738-743, 2016. © 2016 Wiley Periodicals, Inc.


Subject(s)
Animal Feed/analysis , Rumen/physiology , Sheep/physiology , Water/analysis , Animals , Female , Keratins , Optical Fibers , Rain , Rumen/anatomy & histology , Sheep/anatomy & histology , Surface Properties
7.
Environ Manage ; 57(6): 1247-61, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26899738

ABSTRACT

Invasion of the tall grass Brachypodium genuense was observed in an area of the central Apennines (Italy) where the population size of Apennine chamois (Rupicapra pyrenaica ornata) was in strong decline. Since this dominant tall grass threatens biodiversity and forage quality, our hypothesis was that B. genuense abundance influenced that of palatable species for the chamois, depending on their functional traits and distribution patterns. Our sampling design used plots of 10 × 10 m and 1 × 1 m to investigate the plant community level and fine-scale interactions. We analyzed data using correlation, generalized linear models, and redundancy analyses. We found that B. genuense can reach high abundance values on the deepest soils. Its high cover value influences plant community composition by competitive exclusion of subordinate species and suppression of functional features because of temporal or spatial niche overlap. This leads to low cover of palatable species at a fine scale, and to poor pasture quality for chamois at a wider scale. Therefore, we postulated that B. genuense invasion, enhanced by long-term grazing cessation, may reduce the availability of palatable plants for Apennine chamois, especially below the potential timberline (1900-2000 m a.s.l.). The high abundance of B. genuense may amplify the effect of other negative factors, such as competition with red deer (Cervus elaphus) and climate change, in restricting the suitable habitat of the Apennine chamois to the higher sectors of the central Apennines. Thus, we suggested that B. genuense spread should be monitored carefully and plans to control its invasion should be implemented.


Subject(s)
Brachypodium/growth & development , Conservation of Natural Resources/methods , Grassland , Herbivory , Introduced Species/trends , Rupicapra/growth & development , Animals , Biodiversity , Climate Change , Ecosystem , Italy , Population Density , Rupicapra/physiology
8.
Microsc Res Tech ; 75(7): 884-9, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22223350

ABSTRACT

Although the Geographical Information System (GIS), which integrates computerized drawing computer assisted design (CAD) and relational databases (data base management system (DBMS)), is best known for applications in geographical and planning cartography, it can also use many kinds of information concerning the territory. A multidisciplinary project was initiated since 5 years a multidisciplinary study was initiated to use GIS to integrate environmental and ecological data with findings on animal health, ethology, and anatomy. This study is chiefly aimed at comparing two different methods for measuring the absorptive surface of rumen papillae. To this scope, 21 female sheep (Ovis aries) on different alimentary regimes (e.g., milk and forage mixed diet, early herbaceous diet, dry hay diet, and fresh hay diet at the maximum of pasture flowering and at the maximum of pasture dryness) were used; after slaughtering, 20 papillae were randomly removed from each sample collected from four indicator regions of rumen wall, placed near a metric reference and digitally photographed. The images were developed with the ArcGIS™ software to calculate the area of rumen papillae by means of GIS and to measure their mid-level width and length to calculate the papillae area as previously performed with a different method. Spatial measurements were analyzed using univariate and multivariate methods. This work demonstrates that the GIS methodology can be efficiently used for measuring the absorptive surface of rumen papillae. In addition, GIS demonstrated to be a rapid, precise, and objective tool when compared with previously used method.


Subject(s)
Biometry/methods , Diet/methods , Image Processing, Computer-Assisted/methods , Intestinal Absorption , Intestinal Mucosa/anatomy & histology , Rumen/anatomy & histology , Animals , Geographic Information Systems , Intestinal Mucosa/physiology , Rumen/physiology , Sheep
9.
Folia Histochem Cytobiol ; 49(3): 458-64, 2011.
Article in English | MEDLINE | ID: mdl-22038226

ABSTRACT

Mammalian aquaporins (AQPs) are a family of at least 13 integral membrane proteins expressed in various epithelia, where they function as channels to permeate water and small solutes. AQP5 is widely expressed in the exocrine gland where it is likely involved in providing an appropriate amount of fluid to be secreted with granular contents. As regards AQP5 expression in the salivary glands, literature is lacking concerning domestic animal species. This study was chiefly aimed at immunohistochemically investigating the presence and localization of AQP5 in sheep mandibular and parotid glands. In addition, AQP5 immunoreactivity was comparatively evaluated in animals fed with forage containing different amounts of water related to the pasture vegetative cycle, in order to shed light on the possible response of the gland to environmental modifications. Moderate AQP5-immunoreactivity was shown at the level of the lateral surface of mandibular serous demilune cells, not affected by the pasture vegetative cycle or water content. On the contrary, the parotid gland arcinar cells showed AQP5-immunoreactivity at the level of apical and lateral plasma membrane, which was slight to very strong, according to the pasture vegetative development and interannual climatic variations. AQP5 expression is likely due to its involvement in providing appropriate saliva fluidity. Indeed, the lowest AQP5 immunoreactivity was noticed when food water content increased.


Subject(s)
Aquaporin 5/metabolism , Environment , Herbivory , Salivary Glands/metabolism , Sheep/anatomy & histology , Sheep/metabolism , Animal Feed , Animals , Female , Humans , Immunohistochemistry , Plants/chemistry , Plants/metabolism , Salivary Glands/cytology , Water
10.
Vet Ital ; 43(3): 425-9, 2007.
Article in English | MEDLINE | ID: mdl-20422518

ABSTRACT

The morphometric variations of the rumen papillae due to different alimentary diets has been analysed using a geographic information system (GIS), as the preliminary stage of a wider study aimed at creating a geo-database to link environmental data (pasture structure and composition, pastoral value) with parameters measuring animal welfare (body condition score, volatile fatty acids concentration, haematochemical profile) both during a pasture vegetative cycle and in different conditions of animal load on pastures, with the ultimate goal of contributing to grassland management. A first step was to collect samples of rumen wall tissue from different groups of sheep (lambs to milky and mixed diet, and adult at the maximum of flowering and at the end of pasture vegetative cycle) to verify morphometric differences in rumen papillae due to different diets. Wall tissues of rumen samples were removed from the dorsal and ventral sac and preserved in a formalin solution. Twenty papillae from the dorsal and ventral sac were taken from each sample and their images were elaborated with ArcGISTM software. Results show that the morphometric variation of papillae is related with the pasture productivity trend: the maximum size of rumen papillae occurs immediately after the phytomass and flowering spike; in this phase the animals utilise a very nourishing and quantitatively abundant pasture. After this phase, a deterioration of pasture occurs and the surface of rumen papillae surface decreases rapidly. Results obtained further confirm the existence of a close relationship between quality and quantity of phytomass and the extent of rumen papillae absorptive surface, demonstrating the effects of this relationship during a pasture vegetative cycle.

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