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排序方式: 共有201条查询结果,搜索用时 109 毫秒
71.
72.
Marcos Cláudio Pinheiro Rogério Eliane Minervina de Castro Espedito Cezário Martins Jomar Patrício Monteiro Kleibe de Moraes Silva Magno José Duarte Cândido Tereza Cristina Lacerda Gomes Antoine Francis Roux Bloc Ângela Maria de Vasconcelos Eneas Reis Leite Hélio Henrique Araújo Costa 《Tropical animal health and production》2012,45(1):259-266
This study compares both versions of the nutritional requirement system determined by the National Research Council (NRC) version 1985 (NRC85) and NRC version 2007 (NRC07), for finishing lambs in feedlots. Nineteen crossbred lambs were divided in four groups representing four experimental treatments: one diet according to NRC85 and three diets according to NRC07. The diets recommended by NRC07 considers crude protein intake relative to ruminal undegradable protein at 20, 40, and 60 % levels (NRC07/20, NRC07/40, and NRC07/60). Diets were composed of Brazilian semi-arid native grass silage, soybean meal, corn, annatto byproduct, and limestone. Purchases and sales of lambs were done according to average market prices in Brazil. The economic indicators considered pointed that all treatments were viable but NRC07/20 and NRC07/60 were more profitable with similar net present values (NPVs) and internal return rates (IRRs). NRC07/20 was the best option showing an IRR of 17.20 % and a payback period (PP) of 5.07 considering a fixed annual interest rate of 6 %. Sensitivity analysis considering a 10 % raise in variable costs showed negative NPVs, IRRs inferior to the opportunity cost rates adopted and PPs that exceeded the planning horizon of 7 years for both NRC85 and NRC07/40. 相似文献
73.
Lauber B Molitor V Meury S Doherr MG Favrot C Tengvall K Bergvall K Leeb T Roosje P Marti E 《Veterinary immunology and immunopathology》2012,149(1-2):112-118
Canine atopic dermatitis (CAD) is an allergic skin disease associated with IgE and IgG antibodies (Ab) to environmental allergens. The aim of this study was to determine which other factors influence serum Ab levels in CAD-affected and non-affected dogs as this has only been poorly investigated in dogs so far. Total and allergen-specific IgE levels and Dermatophagoides farinae (DF)-specific IgG1 and IgG4 were measured by ELISA in sera of 145 CAD-affected and 271 non-affected Labrador- and Golden retrievers. A multivariable logistic regression analysis including the factors age, breed, gender, castration, clinical CAD status and allergen-specific immunotherapy (ASIT) was performed. Golden retrievers had more frequently total (OR=1.87, 95% CI=1.26-2.87, p<0.01) and specific IgE levels above the threshold value than Labrador retrievers, suggesting that genetic factors influence IgE levels in dogs. Castration was generally associated with low Ab levels (OR=0.43-0.65, p<0.05). Surprisingly, dogs with CAD did not have increased odds for high IgE against any of the allergens tested. ASIT with DF was associated with high DF-specific IgG1 (OR=4.32, 95% CI 1.46-12.8, p<0.01) but was not associated with DF-specific IgG4 or decreased IgE levels. Further studies are needed to understand the role of allergen-specific IgE in CAD and of IgG1 in ASIT. 相似文献
74.
Rojas CL Romera FJ Alcántara E Pérez-Vicente R Sariego C Garcaí-Alonso JI Boned J Marti G 《Journal of agricultural and food chemistry》2008,56(22):10774-10778
The FeEDDHA [iron(3+) ethylenediamine di(o-hydroxyphenylacetic) acid] is one of the most efficient iron chelates employed in the correction of iron clorosis in calcareous soils. FeEDDHA presents different positional isomers: the ortho-ortho (o,o), the ortho-para (o,p), and the para-para (p,p). Of these isomers, the p,p cannot chelate Fe in soil solution in a wide range of pH values, while both o,o and o,p can. The objective of this work was to compare the efficiency of both isomers (o,o and o,p) to provide Fe to two Strategy I plants (tomato and peach) in nutrient solution (pH approximately 6.0), as well as in calcareous soil (pH approximately 8.4; CALCIXEREPT). For this, chelates of both o,o-EDDHA and o,p-EDDHA with 57Fe (a nonradioactive isotope of Fe) were used, where the 57Fe acts as a tracer. The results obtained showed that the o,o isomer is capable of providing sufficient Fe to plants in both nutrient solution and calcareous soil. However, the o,p isomer is capable of providing sufficient Fe to plants in nutrient solution but not in calcareous soil. 相似文献
75.
M E Griot-Wenk E Marti D J DeBoer A L de Weck S Lazary 《Veterinary immunology and immunopathology》1999,70(1-2):117-124
Eight dog IgE-specific reagents including monoclonal and polyclonal antibodies (Ab) and a cross-reactive alpha chain of the human high affinity IgE receptor were mapped to recombinant fragments of the second (IgEf2) and third/fourth (IgEf3/4) domains of the dog IgE heavy chain. In ELISA, five out of eight reagents reacted to solid-phase bound IgEf2, of which two polyclonal Ab bound in addition to IgEf3/4. All Ab which recognized at least one recombinant IgE fragment, also bound to IgE in ELISA, immunoblots, and immunohistochemistry. In contrast, only one monoclonal Ab, that did not bind to the recombinant IgE fragments, reacted with immunoblots of serum and immunohistochemistry. The alpha chain could only be applied to ELISA with serum IgE. Furthermore, there was a wide range of heat-lability of binding reactions. Comparative analysis of available dog IgE-specific reagents enables more in-depth functional studies on IgE-mediated phenomena in dogs, and helps to further establish the dog as an animal model for allergy research. 相似文献
76.
Rayette Souza da Silva Juliana Ralica Tavares Lopes Roberto Vilhena do Espírito Santo Marcos Antnio Souza dos Santos Carlos Alberto Martins Cordeiro Eliane Tie Oba Yoshioka Roselany Corrêa Heitor Martins Júnior Jos Brito de Loureno Júnior 《Aquaculture Research》2020,51(8):3358-3366
Two experiments were carried out to evaluate the effects of palm kernel meal (Elaeis guineensis) as corn (Zea mays) substitutes in tambaqui (Colossoma macropomum) diets based on zootechnical performance, health, characteristics of the muscle, yield and economic efficiency. The first one was carried out in a recirculation aquaculture system for 75 days wherein tambaquis received diets with 0% (T0), 25% (T25), 50% (T50), 75% (T75) and 100% (T100) of corn replacement by palm kernel meal. The second experiment, conducted in ponds for 184 days, tambaquis were fed T0 and T25 diets (selected because showed greater weight gain without health damage). Final weight and weight gain of tambaquis were impaired by the increasing levels of this ingredient on diets, and the feed conversion ratio was worse. The protein efficiency ratio and specific growth rate gradually reduced, while the total number of leucocytes and neutrophils gradually increased. Cholesterol and triglycerides decreased in T75 and T100. Variables analysed in experiment 2 were not affected by treatment, except muscle lipids. Palm kernel meal can replace up to 25% of corn in tambaqui diets since it maintains a balance in economic and zootechnical performance of production. 相似文献
77.
Anatomical dissections of fresh canine fore-limb specimens were carried out on the brachium and antebrachium and cross sections of the antebrachium to identify the location of safe corridors for external skeletal fixator pin insertion. Those areas and lines for safe, hazardous and unsafe corridors were defined and measured along the canine forelimb. Recommendations are made on the safe and effective use of fixator frames in the canine humerus and radius. The canine humerus was considered a concentric bone and no safe corridors could be identified. However, safe areas and lines are described. The distal two-thirds of the medial aspect of the canine radius represents a safe corridor. 相似文献
78.
Anatomical dissections of fresh canine hindlimb specimens were carried out on the femoral region and crus and cross sections of the crus to identify the location of safe corridors for external skeletal fixator pin insertion. Safe, hazardous and unsafe corridors were defined and measured along the canine hindlimb. Recommendations are made on the safe and effective use of fixator frames in the canine femur and tibia, in order to avoid potentially serious complications. No safe corridors were identified in the canine femoral region. The canine tibia is an eccentric bone and its entire medial aspect and part of its cranial aspect lie in a subcutaneous position. These areas are identified as safe for external skeletal fixator pin insertion. 相似文献
79.
Ricardo Aparecido Bento Orivaldo José Saggin-Júnior Rosa Maria Pitard Rosangela Straliotto Eliane Maria Ribeiro da Silva Sílvio Roberto de Lucena Tavares Frederico Henrique Teixeira Gerken de Landa Luiz Fernando Martins Antonia Garcia Torres Volpon 《Water, air, and soil pollution》2012,223(9):5659-5671
Leguminous trees have a potential for phytoremediation of oil-contaminated areas for its symbiotic association with nitrogen-fixing bacteria and arbuscular mycorrhizal fungi (AMF). This study selects leguminous tree associated with symbiotic microorganisms that have the potential to remediate petroleum-contaminated soil. Seven species of trees were tested: Acacia angustissima, Acacia auriculiformis, Acacia holosericea, Acacia mangium, Mimosa artemisiana, Mimosa caesalpiniifolia, and Samanea saman. They were inoculated with AMF mix and nitrogen-fixing bacteria mix and cultivated over five oil levels in soils, with five replicates. The decreasing of total petroleum hydrocarbons (TPH) values occurred especially with S. saman and its symbiotic microorganisms on highest oil soil contamination. Despite the large growth of A. angustissima and M. caesalpiniifolia on the highest level of oil, these species and its inoculated microorganisms did not reduce the soil TPH. Both plants were hydrocarbon tolerant but not able to remediate the polluted soil. In contrast were significative hydrocarbon decrease with M. artemisiana under high oil concentrations, but plant growth was severely affected. Results suggest that the ability of the plants to decrease the soil concentration of TPH is not directly related to its growth and adaptation to conditions of contamination, but the success of the association between plants and its symbionts that seem to play a critical role on remediation efficiency. 相似文献
80.