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131.
小尾寒羊泌乳期母羊能量需要量及代谢规律研究 总被引:4,自引:0,他引:4
选择有代表性的小尾寒羊泌乳母羊6只,分成哺育单羔和双羔两组,每组3只,分泌乳前期(1~30天),泌乳中期(31~60天)和泌乳后期(61~90天)3个阶段进行饲养试验、消化代谢试验、呼吸测热试验及屠宰试验等研究。两组试羊均按NRC(1978)推荐的绵羊泌乳期哺育双羔母羊能量需要量供给代谢能和其它养分。结果表明,在本研究条件下,小尾寒羊泌乳母羊(包括哺育单、双羔者)在整个泌乳期内的平均日干物质(DM)、有机物质(OM)、代谢能(ME)和泌乳量分别为1689g,1571g,19.893MJ和653g。DM、OM和总能(GE)表观消化率分别为70.71%,72.58%和70.34%,代谢率(MEI/DEI)为84.89%。甲烷能占GEI的9.18%。每日畜体产热量(HP)为625.5KJ/kgW0.75。研究还表明:小尾寒羊泌乳母羊的每日维持代谢能和净能需要量分别为582.6和460KJ/kgW0.75,每户1kg原乳需要10802KJ的代谢能。维持效率为0.790泌乳效率为0.479,HI占GEI的18.10%。分析结果证明,试羊的泌乳量、采食量、畜体产热量和能量转化效率在单、双羔之间均无显著差异(P>0.05)。小尾寒羊泌乳母羊的代谢能总需要量(MER)可用下式估计:羊羔:MER=576.9W0.75+10810M;双羔:MER=588.2W0.75+10794M;平均:MER=582.6W0.75+1 相似文献
132.
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134.
Caroline Larsson Anne Vitger Rasmus B Jensen Peter Junghans Anne-Helene Tauson 《Acta veterinaria Scandinavica》2014,56(1)
Background
Overweight and obesity are the most common nutritional disorders in dogs and may lead to various secondary diseases and decreased lifespan. In obesity research, measurement of energy expenditure (EE) and determination of the energy requirements are essential. The objective with this study was to validate and evaluate the suitability of the oral 13C-bicarbonate technique (o13CBT) for measuring EE in dog obesity studies. A further objective was to investigate the impact of body weight (BW) reduction and changes in body composition on the EE when measured under conditions corresponding to the basal metabolic rate (BMR).Results
The EE in five privately owned, overweight dogs was measured simultaneously with the o13CBT and indirect calorimetry (IC) for comparison of the results. Two measurements per dog were performed under the same standardised conditions (i.e. fasted and resting state) at the start, and after completing a 12-week BW reduction program. Additionally, measurements of body composition by Dual-energy X-ray absorptiometry (DEXA) were conducted at the beginning and at the end of the BW reduction program. There were no differences in EE results obtained by the o13CBT and IC. Overweight and the BW reduction did not affect the estimates for the respiratory quotient (RQ) or the recovery factor for the 13C-tracer (RF), both needed when using the o13CBT. The dogs lost 16% (SD ± 2.0) of their initial BW in reduced fat mass (P < 0.001), whereas fat free mass (FFM) remained unchanged. There was no effect of the BW reduction on the determined EE expressed in kJ/kg BW/d, or in kJ/kg BW0.75/d. However, EE was lower (P < 0.001) after the BW reduction program when expressed in relation to FFM (kJ/kg FFM/d).Conclusions
Results from the present study show that the o13CBT can be a used in obesity research to determine EE in fasted dogs and under resting conditions. Furthermore, the results suggest that the BMR does not change with reduced BW in overweight dogs as long as the FFM remains unchanged. This indicates that the BMR to maintain one gram of fat is equal to maintaining one gram of FFM in overweight dogs. 相似文献135.
136.
基于小气候模型的温室能耗预测系统研究 总被引:6,自引:0,他引:6
【目的】建立一个基于温室小气候模型的温室冬季加温所需基础能耗计算机预测系统,为进一步研究中国温室环境的优化调控提供依据。【方法】根据能量平衡原理,综合考虑作物蒸腾对温室运行能耗的影响,建立了温室加温所需基础能耗预测系统。利用温室作物蒸腾和小气候观测试验资料确定了温室小气候模型中的作物参数,并用上海两个Venlo型自控温室2001年~2003年3个冬季的实际耗煤量对系统预测结果进行了检验。【结果】对两个温室冬季加温能耗预测结果与实际耗煤量统计分析回归方程分别为(x和y分别为实际值和预测值)y=0.8526x和y=0.8321x;决定系数R2分别为0.85和0.90;相对误差分别为27%和29%。结果表明,系统对能耗预测结果与实际耗煤量趋势一致。【结论】本研究建立的温室加温能耗预测系统是建立在温室小气候模型的基础上,其原理具有普适性,因此具有通用性强的特点。 相似文献
137.
The effects of Phomopsis longanae Chi infection on browning development and disease incidence in relation to energy status in pericarp of harvested longan fruit were investigated. Longan fruit were inoculated for 5 min with P. longanae at 104 spores mL−1, while fruit dipped in sterile deionized water were used as control. These fruits were stored at (28 ± 1) °C and 90% relative humidity for up to five days. The results showed that the browning index, disease incidence, cellular membrane permeability and AMP content increased but the contents of ATP and ADP, and energy charge decreased in pericarp of longan fruit infected by P. longanae. It was suggested that P. longanae infection caused energy deficiency in longan fruit, possibly resulting in accelerated senescence and decreased resistance to pathogen, and thus promoted browning development and disease occurrence. 相似文献
138.
[Objective]The energy productivity potential of Saccharum spontaneum L.germplasm resources as energy plants was discussed in this paper.[Method]The energy productivity potential of Saccharum spontaneum L.germplasm resources collected from the wild was assessed from the aspects of cellulose,semicellulose,lignin and crude ash contents and caloric value.[Result]The total content of cellulose and semicellulose ranged from 41.75%to 69.13%,the lignin content ranged from 2.16%to 11.75%,the crude ash content ranged from 4.79%to 9.34%and the caloric value ranged from 16.00 to 17.69 MJ/kg among the 30 Saccharum spontaneum L.germplasms.Compared to other plants,Saccharum spontaneum L.had higher contents of cellulose and semicellulose,a higher caloric value but lower contents of lignin and crude ash.[Conclusion]From the perspective of producing fuel ethanol with lignocellulose,Saccharum spontaneum L.has a great potential for development as an energy plant. 相似文献
139.
Seedling crops of gazania, geranium, marigold, mimulus, pansy, verbena and vinca were grown to 60% anthesis in three greenhouse temperature regimes: (a) 26 °C day/6 ± 3 °C night (LT), with a 16.5 °C mean daily temperature (MDT), (b) 26 °C day/17 ± 4 °C night, with a 21 °C MDT, and (c) variable day/night temperatures in response to heating and cooling by a phase change material energy storage module (PCM) with an 8 ± 2 °C night and a 16 °C MDT. Crops bloomed from 2 to 17 days earlier in the 26 °C/17 °C greenhouse. The morphological characteristics of all cultivars of gazania, mimulus, pansy and verbena, geranium and vinca were similar regardless of greenhouse temperature regime. Marigold diploid and triploid cultivars and mimulus were morphologically more variable than the other bedding plant species. Crops grown in the PCM and LT greenhouses had virtually identical morphological characteristics and bloomed in about the same number of days. Plant height was not affected by DIF environments in the greenhouses. The PCM and LT greenhouses had a similar MDT, but the distribution of numbers of hours of mean daily temperatures was different. 相似文献
140.
In this study, the energy budget of the Manila clam, Ruditapes philippinarum, was evaluated after one-week acclimation periods at 5, 10, 15, 20, and 25°C. Small clams (151 ± 12 mg DW) and large clams
(353 ± 16 mg DW) were fed with the microalgae, Isochrysis galbana. Filtration rate, ingestion rate, assimilation efficiency, oxygen-consumption rate, and ammonia excretion rate were measured.
Both filtration rate and ingestion rate of small and large clams were found to be related to temperature. The highest Q
10 values were measured in the range 15–20°C for both small and large clams. Assimilation efficiency of both small and large
clams was not significantly influenced by temperature, although the maximum mean values were detected at 20°C. Oxygen consumption
rate and ammonia excretion rate of small and large clams were found to be related directly to temperature over the entire
range, with a maximum being detected at 25°C. The highest Q
10 value was estimated in the range 10–15°C with regard to oxygen consumption rate, and in the range of 15–20°C with regard
to ammonia excretion rate. Scope for growth (SFG) was positive at all temperatures, achieving a maximum value at 20°C in both
small and large clams, primarily as a consequence of the enhanced ingestion rate which offset the concomitant elevation in
the metabolic rate. In this study we have estimated the thermal optimum for this species at 20°C. 相似文献