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91.
A study was conducted with the objective to characterize the morphology of Pelibuey sheep in the state of Colima, Mexico. A total of 386 sheep were scored for 12 body measurements in addition to live weight and five racial and eight functional indices were calculated. The influence of sex on the body measurements and indices was analyzed, and morphological harmony was determined through Pearson correlation. The sexual dimorphism was 1.21, with males being 67 % heavier than females. Females and males had a high and moderate degree of harmony in their morphological model, respectively. Pelibuey sheep were dolichocephalous, tended to be medium- to large-sized according to the thoracic index, with a convex curve rump; they were a homogeneous breed, well adapted to environmental and production conditions of the state of Colima, Mexico, and show an undefined zootechnical aptitude and therefore a great potential to be oriented towards meat or milk production through genetic selection or terminal crossbreeding systems using specialized breeds.  相似文献   
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With the move away from use of mouse bioassay (MBA) to test bivalve mollusc shellfish for paralytic shellfish poisoning (PSP) toxins, countries around the world are having to adopt non-animal-based alternatives that fulfil ethical and legal requirements. Various assays have been developed which have been subjected to single-laboratory and multi-laboratory validation studies, gaining acceptance as official methods of analysis and approval for use in some countries as official control testing methods. The majority of validation studies conducted to date do not, however, incorporate shellfish species sourced from Latin America. Consequently, this study sought to investigate the performance of five alternative PSP testing methods together with the MBA, comparing the PSP toxin data generated both qualitatively and quantitatively. The methods included a receptor binding assay (RBA), two liquid chromatography with fluorescence detection (LC-FLD) methods including both pre-column and post-column oxidation, liquid chromatography with tandem mass spectrometry (LC-MS/MS) and a commercial lateral flow assay (LFA) from Scotia. A total of three hundred and forty-nine shellfish samples from Argentina, Mexico, Chile and Uruguay were assessed. For the majority of samples, qualitative results compared well between methods. Good statistical correlations were demonstrated between the majority of quantitative results, with a notably excellent correlation between the current EU reference method using pre-column oxidation LC-FLD and LC-MS/MS. The LFA showed great potential for qualitative determination of PSP toxins, although the findings of high numbers of false-positive results and two false negatives highlighted that some caution is still needed when interpreting results. This study demonstrated that effective replacement methods are available for countries that no longer wish to use the MBA, but highlighted the importance of comparing toxin data from the replacement method using local shellfish species of concern before implementing new methods in official control testing programs.  相似文献   
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Plant Foods for Human Nutrition - Organosulfur compounds (OSCs) of garlic have various health benefits including anti-hypertensive effect. It has been described that volatile OSCs uptake occurs...  相似文献   
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On the basis of a digital analysis of radiograms it was checked if, and to what extent, the extended loading of one of the sides of the body of racehorses leads to differences in the microstructure of the spongy bone of the bilateral pastern bones of the thoracic limbs. The research material consisted of radiograms of the pastern bones of the right and left thoracic limbs of racehorses. On the basis of computer image radiological analysis with the use of the "Trabecula,, programme, a quantative evaluation of the structure of the spongy bone of the pastern bones was conducted. It was noted that the differences between the right and the left pastern bones, despite extensive loading of the left thoracic limb, were not statistically significant as far as all studied parameters of the trabecula structure of the spongy bone were concerned.  相似文献   
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Biological soil crusts are widely distributed in arid and semiarid regions. They have an important eco- logical role, especially by modifying physical and chemical properties of soils. Biological crusts may also modify seed germination and seedling establishment. The effects vary widely according to the type of crust and the vas- cular plant species. The objective of this study was to determine the effect of moss-dominated biological soil crusts on the emergence, biomass and survival of Poa ligularis Nees ex Steud. under different irrigation regimes. We col- lected seeds of P. ligularis and biological soil crusts composed of two species of mosses: Syntrichia princeps (De Not.) Mitt and Ceratodon purpureus (Hedw.) Brid. from an area in the Monte of Argentina. The result showed that seedling emergence of P. ligularis was higher in treatments with bare soil than in soil covered by crusts, and also in those with watering to field capacity. Mean emergence time was higher in treatments with bare soil and watering to field capacity. Seedling biomass also showed significant differences between treatments. These results suggest that biological soil crusts dominated by mosses do not promote P. ligularis emergence, although they would not affect its survival.  相似文献   
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The inflammatory response to vigorous exercise ranges from the mild symptoms of delayed-onset muscle soreness to debilitating injuries affecting soft tissue, joint, and bone. Although there is a great deal of information available on the inflammatory response to exercise in human athletes, less information is available regarding the inflammatory response to exercise in young horses undergoing training for racing careers. Here, we assessed the cytokine response to exercise in a group of young Thoroughbred racehorses during their initial training. Because there is interest in nonpharmacologic approaches to control or ameliorate exercise-induced inflammation, we also examined the anti-inflammatory effect of a nutritional supplement fed to half of the horses undergoing training. Twenty-five Thoroughbred horses aged 2 years were followed through their initial race training. Peripheral blood samples were collected at various times during the exercise for the quantitation of lactic acid, oxidative stress, and inflammatory cytokine gene expression. There was an intensity-dependent effect of exercise on lactate, malondialdehyde, and proinflammatory cytokine gene expression. Although training itself was associated with an overall reduction in inflammatory markers, horses receiving the supplement exhibited further reductions in their indicators of inflammation. As such, this study provides novel evidence of nutritional supplementation reducing postexercise inflammation.  相似文献   
100.
Previous research suggested that clinical manifestations, histopathological lesions, and even infection maintenance in the course of canine monocytic ehrlichiosis (CME) are directly related to the immune response developed by the host. In the present study, blood lymphocyte subsets were analyzed by multiparametric flow cytometry in 37 dogs with naturally occurring CME and 47 healthy dogs used as controls. T, T helper (Th), T cytotoxic (Tc), B, non-T, non-B lymphocytes and those that express MHC class II were characterized in every dog. Animals with CME showed higher relative values of T and Tc cells and a higher absolute number of Tc cells in peripheral blood. The percentage of Th cells and the absolute and relative values of B cells were higher in healthy animals than in CME-affected dogs. The significance of these changes on the pathogenesis of natural Ehrlichia canis infection in dogs needs further evaluation.  相似文献   
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