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31.
The objective of this study was to evaluate the coefficient of total tract apparent digestibility (CTTAD) of dietary nutrients, endogenous fat loss (EFL), dietary metabolizable energy (ME) content, coefficient of true digestibility (CTD) of fat and faecal parameters of dogs. A total of 16 puppies and 8 adult dogs were distributed according to a double Latin square experimental design. A basal diet was formulated, to which increasing levels (60, 120 and 180 g/kg) of poultry offal fat oil were added. EFL was estimated using hyperbolic and linear regression as a function of LW/day and dry matter (DM) intake, respectively, and the CTD of fat was calculated. The CTTAD of acid-hydrolysis ether extract (AHEE) and ME content increased as dietary poultry offal fat level increased both in adult dogs and in puppies (p < .05). The CTTAD of DM and crude protein were higher in adult dogs than in puppies. EFL was estimated by hyperbolic regression as y = 98.1094 − 13.6202/x and y = 99.1280 − 26.1366/x, where y = CTTAD of AHEE (%) and x = AHEE intake/kg BW, for adult dogs and puppies, respectively, which yielded EFL values of 138 and 262 mg AHEE per kg BW per day for adult dogs and puppies respectively. The EFL estimated by linear regression was 7.89 g and 8.97 g/kg DM intake for adult dogs and puppies respectively. The CTD estimated by both methodologies was higher in puppies than in adults (p < .05). Lower faecal DM and score, and higher ammonia production were obtained in puppies than adult dogs (p < .05). The results indicate good fat utilization and that fat digestibility is underestimated, as the CTTAD of AHEE does not take into account EFL, particularly at low-fat inclusion levels and in growing dogs, which have greater EFL than adult dogs.  相似文献   
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This study investigated the analgesic and systemic effects of intramuscular (IM) versus epidural (EP) administration of tramadol as an adjunct to EP injection of lidocaine in cats. Six healthy, domestic, shorthair female cats underwent general anesthesia. A prospective, randomized, crossover trial was then conducted with each cat receiving the following 3 treatments: EP injection of 2% lidocaine [LEP; 3.0 mg/kg body weight (BW)]; EP injection of a combination of lidocaine and 5% tramadol (LTEP; 3.0 and 2.0 mg/kg BW, respectively); or EP injection of lidocaine and IM injection of tramadol (LEPTIM; 3.0 and 2.0 mg/kg BW, respectively). Systemic effects, spread and duration of analgesia, behavior, and motor blockade were determined before treatment and at predetermined intervals afterwards. The duration of analgesia was 120 ± 31 min for LTEP, 71 ± 17 min for LEPTIM, and 53 ± 6 min for LEP (P < 0.05; mean ± SD). The cranial spread of analgesia obtained with LTEP was similar to that with LEP or LEPTIM, extending to dermatomic region T13–L1. Complete motor blockade was similar for the 3 treatments. It was concluded that tramadol produces similar side effects in cats after either EP or IM administration. Our findings indicate that EP and IM tramadol (2 mg/kg BW) with EP lidocaine produce satisfactory analgesia in cats. As an adjunct to lidocaine, EP tramadol provides a longer duration of analgesia than IM administration. The adverse effects produced by EP and IM administration of tramadol were not different. Further studies are needed to determine whether EP administration of tramadol could play a role in managing postoperative pain in cats when co-administered with lidocaine after painful surgical procedures.  相似文献   
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Accurate estimation of biomass in natural vegetation sites remains a challenge. Modeling biomass growth and production in Cerrado areas is crucial to understanding the vegetation succession process, especially regarding the changes in biomass accumulation over time. Thus, our objective was to model the growth and production of woody aboveground biomass (living and total) in a cerrado stricto sensu monitored for 27 years after implementing management systems. As expected, the basal area (with a diameter taken at 30 cm from the ground level) is the most important predictor variable and showed a higher correlation with the biomass stocks and allowed accurate and consistent estimates of these accumulated stocks over time. Future estimates of biomass production, generated from growth models that estimate production as a function of parameters observed at previous ages, indicate that maximum stocks of living (25.86?±?0.15 Mg ha?1 [mean?±?standard deviation]) and total aboveground biomass (26.11?±?0.15 Mg ha?1) are expected for a period between 28 and 30 years after the implementation of the management systems, with maximum mean annual increment between 23 and 27 years. Furthermore, the systems of equations obtained simulated reductions up to 30% of biomass after the occurrence of a forest fire at 23 years. Thus, our study can be useful for the decision-making process and developing public policies and strategies for managing and conserving natural resources in the Cerrado biome.

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Genetic Resources and Crop Evolution - Jatropha (Jatropha curcas L.) is an oleaginous potential, howetever, some studies report that there is low genetic diversity in Brazilian genotypes....  相似文献   
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Apple blotch (Marssonina coronaria) is a foliar disease of increasing importance globally. Methods to quantify the disease and knowledge about epidemiology are required for new studies on the disease. The objectives of this study were to develop a standard area diagram set (SADs) to assess apple blotch severity and to describe the temporal progress of the disease under field conditions on older and younger leaves of two apple cultivars. For the development of SADs, symptomatic leaves were collected and scanned to obtain the actual severity. Based on the pattern of the disease, a SADs was elaborated and validated. Leaf severities were estimated without and with SADs by 12 raters to validate the tool. After validation, the SADs was used to assess apple blotch in older and younger leaves of selected shoots during the vegetative cycle of cvs. Eva and Gala. SADs severities ranged from 0.2 to 96%. Accuracy, precision, and reliability of the estimates were significantly improved when the SADs was used. In the field, the onset of apple blotch was in late spring and greater increases in severity occurred during summer. Rates of disease progress ranged from 0.09 to 0.13. Epidemics were different in older and younger leaves at the end of the apple vegetative cycle for both cultivars tested. Our work provided a tool for apple blotch quantification and described the disease progress curve under subtropical conditions, which can contribute as basis for future studies.

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Soybean [Glycine max (L.) Merril] is the leading food crop worldwide, and selection of soybean genotypes for different levels of soil acidity may raise crop yield without the need to increase in planted area. An experiment in greenhouse conditions was conducted to determine the effects of two lime rates on soil chemical properties, grain yield (GY), yield components, nutritional status and physiological components of 15 soybean genotypes adapted to tropical and subtropical conditions. Genotypes BMX Apolo RR, BMX Potência RR, BRS 295RR, BRS 359RR, FPS Solar IPRO and TMG 716 IRR were the least responsive to soil acidity reduction, and BMX Turbo RR and BRS 360RR were the most responsive. Number of pods per pot, shoot dry weight yield, GY, photosynthesis, stomatal conductance, transpiration and chlorophyll increased significantly with increase in lime rate. Cultivar FPS Solar IPRO showed the highest foliar P, K, Ca and Mg concentrations in soybean, which was not observed in the grain, indicating the presence of genetic factors and the dilution effect on nutrient uptake.  相似文献   
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Abstract

Continuous limestone application can inhibit the copper (Cu) uptake by plants. This experiment was carried out in greenhouse conditions using two soils (Typic Oxisol and Typic Entisol) with different clay and soil organic matter (SOM) levels to evaluate the effects of liming on Cu fertilization. The treatments consisted of two dolomitic limestone rates (0 and 7.5?g per pot, equivalent to 0 and 5.0?Mg ha?1) and five Cu rates (0, 2, 4, 8, and 16?mg kg?1). Regardless of the soil type, the limestone and Cu rate interaction did not affect the grain yield (GY), however, they did increase the productivity, shoot dry weight yield (SDWY), number of grains per pod, number of pods per pot, pod weight per pot, weight of 100 seeds, root volume, photosynthetic rate, and chlorophyll, and Ca, Mg, and Cu contents in the soil and leaves. It was concluded that for soybeans cultivated in Typic Entisol and Typic Oxisol, there was no association between 5.0?Mg ha?1 of limestone and the Cu rates. However, in isolation, limestone and Cu rate caused a significant increase in the soybean productivity, physiological components, and yield characteristics.  相似文献   
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