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Anna Assenza Francesco Tosto Giuseppe Piccione Francesco Fazio Joana Nery Emaneula Valle Domenico Bergero 《Journal of Equine Veterinary Science》2012
Controversial results on lipid utilization as an energy source during training in horses are found in the literature. The objective of this study was to assess blood lipid profile during different training programs in horses. Seventeen Standardbred horses (400 ± 50 kg) and 17 Thoroughbred horses (380 ± 15 kg) followed different training programs. Blood lipid profile, including triglycerides (TGs), total cholesterol, high-density lipoprotein (HDL), and low-density lipoprotein (LDL), was analyzed, and very-low-density lipoprotein (VLDL) concentration was calculated. Data were analyzed using Student t test, and linear regressions were done. Cholesterol and LDL decreased during training programs in Standardbred trotters (P = .0001 and P = .0053, respectively), and VLDL was found to be close to the significance level (P = .053). Blood lipid profile, including TGs (P = .0014), cholesterol (P = .0057), HDL (P = .0128), LDL (P = .0091), and VLDL (P = .0014), varied throughout the training program in Thoroughbred horses. Negative slope of blood lipids and positive slope of TG linear regression in Standardbred trotters were significant for all parameters (P ≤ .05), whereas cholesterol and LDL regression showed poor P and r2 values and HDL P value was slightly above the significance level (P = .069) in Thoroughbred horses. TGs and VLDL showed a positive linear trend in Thoroughbred horses (P = .002). Exercise and different training programs lead to significant variations of lipid profile and lipid utilization in horses. Lipid utilization as an energy source improved with training in Standardbred trotters, whereas this was not the case in Thoroughbred horses. Further studies on the effect of training programs using different conditions and horse breeds would be necessary to understand lipid utilization as an energy source in athletic horses. 相似文献
43.
There is increasing interest in developing criteria to evaluate the environmental implications of intensive agricultural land use. This implies discriminating between nature and man-made effects upon structural and functional attributes of agroecosystems. Adequate indicators of these combined effects should be cost efficient yet compatible with the core of ecological theory on biodiversity, spatial organization and ecosystem stability. We developed resistance-resilience metrics of plant growth to evaluate the intensity of agricultural use in a temperate irrigated basin in southern Argentina. The metrics are based on an analysis of the components of a temporal series of vegetation indices computed at a low resolution from available globally remote sensed reflectance imagery. We related the developed metrics to the properties of the soils and plant canopies observed at field scale and high-resolution imagery of the basin. Soil depth, soil erosion status and land fragmentation account for large fractions of the variance of the distribution of functional groups of the plant canopies and are also correlated with smaller scale attributes of land vegetation cover. Resistance-resilience indicators constitute a cost-efficient and adequate approach to evaluate the degree of intensification of land agricultural use. 相似文献
44.
F. B. Navarro M. A. Ripoll M. N. Jimnez E. De Simn F. Valle 《Land Degradation \u0026amp; Development》2006,17(1):73-87
Twelve soil‐preparation techniques used in afforestation were applied and 16 environmental variables were measured to test their effects on vegetation abundance, diversity, and cover in semiarid abandoned farmland located in southeastern Spain. The soil‐preparation techniques consisted of punctual treatments—making a hole and constructing a plantation bench with different types of machinery; linear treatments—making furrows along contour lines; and surface treatments—that prepare the soil in general all over the plantation surface. Variables measured were the surface and volume affected by the soil‐preparation treatments, distance from sample quadrats to the remnants of natural vegetation, surface runoff estimated by slope angle, and some edaphic characteristics such as gravel content, active lime, CaCO3, phosphorus, oxidizable organic matter, total soil nitrogen, pH, potassium, salinity, and clay, silt and sand content. The multivariate contrasts obtained demonstrated the existence of a significant relationship between species, samples and environmental variables. Both the distance of the quadrats from the remnants of natural vegetation and the volume of soil removed in different treatments were very weighty variables in the explanation of the variance of data, negatively affecting overall vegetation development. The accumulation or loss of surface runoff and the CaCO3 content in soil were also important variables to explain abundance and diversity data. However, not all the species responded to the variables analysed in the same way. Identification of non‐uniform spatial patterns that significantly affect vegetation suggests that afforestation policies and conservation and management strategies in these semiarid abandoned lands should always take into consideration the quality of the whole landscape. Voluminous soil treatments for afforestation should be avoided. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
45.
Spatial and temporal variability of physical properties of Aquands under different land uses in southern Chile 下载免费PDF全文
José Dörner Dorota Dec Oscar Thiers Leandro Paulino Felipe Zúñiga Susana Valle Oscar Martínez Rainer Horn 《Soil Use and Management》2016,32(3):411-421
The aquands found in southern Chile are derived from volcanic ash and contain high levels of organic matter. Due to the presence of an impermeable stratum, they have shallow soil profiles, which induce waterlogging for several months each year. These fragile soils, locally known as ‘Ñadi’, cover an area of 475 000 hectares and have undergone intensive land use changes, which have affected the soil physical properties. These are still not well understood but are relevant for the design of efficient drainage systems. The aim of this research was to analyse the impact of the land use change in Ñadi soils on the spatial and temporal variability of their soil physical properties. For the land use change from secondary native forest (sNF) to naturalized grassland (NG), the effective soil depth was measured at defined points. Time‐ and space‐dependent changes of water‐table depth and penetration resistance were recorded. Volumetric water content and soil temperature were measured with sensors installed at three depths and the water retention curve and air permeability at these depths were also determined. The changes in land use over time have induced a reduction in soil depth. Soils under NG showed a smaller soil water storage capacity, air capacity and permeability compared with soils under sNF, as well as waterlogging during winter and greater mechanical strength and soil profile temperatures during summer. Therefore, the land use change affected the spatial and temporal variability of soil physical functions across the field. 相似文献
46.
Stella de Faria Valle Joanne B. Messick Andrea Pires dos Santos Luiz Carlos Kreutz Naila Cristina Blatt Duda Gustavo Machado Luis Gustavo Corbellini Alexander Welker Biondo Felix Hilario Diaz González 《Comparative immunology, microbiology and infectious diseases》2014
Hemoplasmas are ubiquitous pleomorphic and epicellular bacteria detected in erythrocytes in several species. In Brazil, studies on hemoplasmas have not included information on occurrence, clinical signs, and risk factors in dogs. This paper investigates the occurrence of hemoplasmas in dogs, focusing on risk factors and clinical status. Conventional PCR for the four types of canine hemoplasmas was performed in 331 blood samples collected from dogs clinically treated at a teaching veterinary hospital. Of all samples, 17/331 (5.1%) were positive for Mycoplasma haemocanis and 6/331 (1.8%) were positive for a ‘Candidatus Mycoplasma haemominutum-like’ organism. Risk factors included the presence of vectors, old age, dog bite wounds, and neoplastic diseases. In the multivariate analysis, a 4.40 odds ratio in dogs with vector-borne diseases indicated risk for hemoplasmosis. There was correlation between hemoplasma infection and neoplastic disease, suggesting that neoplastic conditions are a risk factor for hemoplasma infection in dogs. 相似文献
47.
G. Elise Nagel-Alne Leif J. Asheim J. Brian Hardaker Liv Sølverød Dag Lindheim Paul S. Valle 《Preventive veterinary medicine》2014
The aim of this study was to evaluate the profitability to dairy goat farmers of participating in the Healthier Goats disease control and eradication programme (HG), which was initiated in 2001 and is still running. HG includes the control and eradication of caprine arthritis encephalitis (CAE), caseous lymphadenitis (CLA) and paratuberculosis (Johne's disease) in Norwegian goat herds. 相似文献
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49.
Chevallier S Colonna P Buléon A Della Valle G 《Journal of agricultural and food chemistry》2000,48(4):1322-1326
The structure of short dough and biscuit has been characterized at a macroscopic level (dimensions, bulk structure) and a microscopic level (starch damage, protein aggregates, microstructure) by physical and biochemical methods. The baking process of short dough induces a large decrease of the product bulk density from 1.26 to 0. 42 (+/-0.01) g.cm(-)(3) for final biscuit, leading to a cellular solid with a thin colored surface and a porous inner structure. Proteins appear aggregated in biscuit when compared to short dough, whereas starch granules remain almost intact in biscuits. The components which are involved in the cohesiveness of short dough and biscuit final structure have been identified. They suggest that short dough is a suspension of solid particles in a liquid phase being an emulsion of lipids in a concentrated sugar solution. The role of sugars in biscuit structure suggest that biscuit structure is a composite matrix of protein aggregates, lipids and sugars, embedding starch granules. 相似文献
50.
del Valle Juana Cristina Zanazzi Aldo Nahuel Rodriguez Yamila Eliana Haran Nora Selma Laitano María Victoria Mallo Juan Carlos Fernández-Gimenez Analía Verónica 《Aquaculture International》2022,30(4):1645-1658
Aquaculture International - During the early ontogeny, the transition from endogenous (yolk protein) to exogenous feeding (artificial diets) represents a critical period linked to the... 相似文献