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151.
152.
Elizabeth Schwegler Augusto Schneider Paula Montagner Diego Andres Velasco Acosta Luiz Francisco Machado Pfeifer Eduardo Schmitt Viviane Rohrig Rabassa Francisco Augusto Burkert Del Pino Helenice de Lima Gonzalez Cláudio Dias Timm Marcio Nunes Corrêa 《Tropical animal health and production》2013,45(7):1549-1555
The aim of this study was to measure changes in biochemical markers in the peripartum period of primiparous Holstein cows diagnosed with subclinical and clinical mastitis. In this study, 37 dairy cows were monitored daily during milking until 60 days postpartum and were categorized according to the occurrence of clinical mastitis (group mastitis (GM), n?=?9) or subclinical mastitis (group subclinical mastitis (GSUB), n?=?10) or absence of symptoms (control group (CG), n?=?18). Blood samples were collected weekly from ?30 to 60 days from calving. Samples were grouped for prepartum (?30 to 0 days from calving), early postpartum (0 to 30 days from calving), and late postpartum (30 to 60 days from calving) periods. Prepartum serum non-esterified fatty acid (NEFA) concentration was higher in GM than in CG (P?<?0.01). In addition, CG had higher prepartum serum glucose concentration than GM (P?=?0.03). In the early postpartum period, aspartate aminotransferase (AST) activity was lower in CG than in GSUB (P?<?0.05), and in the late postpartum period, AST activity was lower in CG than GSUB and GM (P?=?0.01). Somatic cell count was higher during the early and late postpartum periods for GM and GSUB when compared to CG (P?<?0.01). In this study, primiparous cows with low glucose and higher NEFA in the prepartum were more susceptible for mastitis in the early postpartum, probably due to low immune function associated to a more negative energy balance. In sum, increased prepartum serum NEFA concentration and decreased glucose in primiparous cows were associated with clinical mastitis incidence in the postpartum period. 相似文献
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Benjamín Costas Cláudia Aragão Jorge Dias António Afonso Luís E. C. Conceição 《Fish physiology and biochemistry》2013,39(5):1141-1151
Amino acids (AA) regulate key metabolic pathways, including some immune responses. Therefore, this study aimed to assess whether an increased availability of dietary AA can mitigate the expected increase in plasma cortisol and metabolites levels due to high stocking density and its subsequent immunosuppression. Senegalese sole (Solea senegalensis) were maintained at low stocking density (LSD; 3.5 kg m?2) or high stocking density (HSD; 12 kg m?2) for 18 days. Additionally, both treatments were fed a control or a high protein (HP) diet (LSD, LSD HP, HSD and HSD HP). The HP diet slightly increased the levels of digestible indispensable AA, together with tyrosine and cysteine. HSD was effective in inducing a chronic stress response after 18 days of treatment since fish held at HSD presented higher plasma cortisol, glucose and lactate levels. Moreover, this increase in stress indicators translated in a decrease in plasma lysozyme, alternative complement pathway (ACP) and peroxidase activities, suggesting some degree of immunosuppression. Interestingly, while plasma glucose and lactate levels in HSD HP specimens decreased to similar values than LSD fish, plasma lysozyme, ACP and peroxidase activities increased, with even higher values than LSD groups for ACP activity. It is suggested that the HP diet may be used as functional feed since it may represent a metabolic advantage during stressful events and may counteract immunosuppression in sole. 相似文献
156.
Ayodele Ebenezer Ajayi Moacir de Souza Dias Junior Nilton Curi Cezar Francisco Araujo Junior Thiago Tadeu Teixeira Souza Alberto Vasconcellos Inda Junior 《Soil & Tillage Research》2009,105(1):122-127
In this study, strength attributes and compaction susceptibility of the main classes of Brazilian Latosols (Oxisols), under native vegetation, were studied using the load bearing capacity models relating precompression stress, compression index and water potential through statistical regression models. These models were developed based on the results of the analysis of undisturbed soil samples collected at the B horizon at the different sites. The results showed that the maximum value of the compression index was 0.53 for the Acric Red Latosol, indicating its higher susceptibility to soil compaction. The Dystrocohesive Yellow Latosol had the highest load bearing capacity, while the Acric Red Latosol had the lowest one. The Dystrocohesive Yellow Latosol due to its high load bearing capacity and bulk density (mechanical resistance) behave similarly to hardsetting soil, in which the plants root system has severe physical restrictions to explore deeper horizons during the dry periods. Differences in the load bearing capacity and compaction susceptibility were found to be influenced by soil structure which is associated with clay mineralogy in these very weathered-leached soils and water potential. The study also showed that soil compression index is influenced by water potential and clay mineralogy also. Our work has laid a foundation for estimation of compaction susceptibility of Latosols. 相似文献
157.
Montados are silvo-pastoral systems, typical of the western Mediterranean Basin. When well managed, these ecosystems provide relevant ecosystem services and biodiversity conservation. In the northern part of the Mediterranean Basin, cork oak areas are mainly privately owned and a source of income to landowners, chiefly through cork and livestock production. Sustainable use is essential to maintain the ecological sustainability and socio-economic viability of these ecosystems. Biodiversity conservation and non-provisioning ecosystem services may generate additional incentives promoting sustainable use and conservation of montados, but require adequate mapping and identification. The high conservation value forest (HCVF) framework allows systematic inventory of biodiversity and non-provisioning ecosystem services and is widely applied in forest ecosystems. Here we exemplify the application of HCVF to the cork oak landscape of southern Portugal using a WebGIS tool that integrates the HCVF framework, in conjunction with Pareto optimization, to identify areas important for the conservation of biodiversity and ecosystem services. We present a case study using threatened bird and reptile species, as examples of biodiversity attributes, and carbon storage and water recharge rate of aquifers, as examples of ecosystem services attributes. We identify those areas in a cork oak landscape of southern Portugal where biodiversity and ecosystem services attributes are optimized. These areas can be prioritized for implementing conservation mechanisms, such as payment for ecosystem services, to promote sustainable forest management. 相似文献
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Caio Rodrigo Dias de Assis Amanda Guedes Linhares Vagne Melo Oliveira Renata Cristina Penha França Juliana Ferreira Santos Marina Marcuschi Elba Verônica Matoso Maciel Carvalho Ranilson Souza Bezerra Luiz Bezerra Carvalho Jr. 《Fish physiology and biochemistry》2014,40(6):1659-1668
Brain cholinesterases from four fish (Arapaima gigas, Colossoma macropomum, Rachycentron canadum and Oreochromis niloticus) were characterized using specific substrates and selective inhibitors. Parameters of catalytic efficiency such as activation energy (AE), k cat and k cat/k m as well as rate enhancements produced by these enzymes were estimated by a method using crude extracts described here. Despite the BChE-like activity, specific substrate kinetic analysis pointed to the existence of only acetylcholinesterase (AChE) in brain of the species studied. Selective inhibition suggests that C. macropomum brain AChE presents atypical activity regarding its behavior in the presence of selective inhibitors. AE data showed that the enzymes increased the rate of reactions up to 1012 in relation to the uncatalyzed reactions. Zymograms showed the presence of AChE isoforms with molecular weights ranging from 202 to 299 kDa. Values of k cat and k cat/k m were similar to those found in the literature. 相似文献
160.
The antimicrobial activity of the methanol extract from Solidago microglossa roots, essential oil from its aerial part and some isolated compounds was investigated. The oil exhibited concentration-dependent activity against all the tested bacteria and yeasts. 相似文献