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101.
Emissions of N2O were measured following addition of 15N‐labelled residues of tropical plant species [Vigna unguiculata (cowpea), Mucuna pruriens and Leucaena leucocephala] to a Ferric Luvisol from Ghana at a rate of 100 mg N/kg soil under controlled environment conditions. Residues were also applied in different ratio combinations with inorganic N fertilizer, at a total rate of 100 mg N/kg soil. N2O emissions were increased after addition of residues, and further increased with combined (ratio) applications of residues and inorganic N fertilizer. However, 15N‐N2O production was low and short‐lived in all treatments, suggesting that most of the measured N2O‐N was derived from the applied fertilizer or native soil mineral N pools. There was no consistent trend in magnitude of emissions with increasing proportion of inorganic fertilizer in the application. The positive interactive effect between residue‐ and fertilizer‐N sources was most pronounced in the 25:75 Leucaena:fertilizer and cowpea:fertilizer treatments where 1082 and 1130 mg N2O‐N/g residue were emitted over 30 days. N2O (loge) emission from all residue amended treatments was positively correlated with the residue C:N ratio, and negatively correlated with residue polyphenol content, polyphenol:N ratio and (lignin + polyphenol):N ratio, indicating the role of residue chemical composition in regulating emissions even when combined with inorganic fertilizer. The positive interactive effect in our treatments suggests that it is unlikely that combined applications of residues and inorganic fertilizer can lower N2O emissions unless the residue is of very low quality promoting strong immobilisation of soil mineral N. 相似文献
102.
Erin Massender Luiz F. Brito Angela Cnovas Christine F. Baes Delma Kennedy Flavio S. Schenkel 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2021,138(1):91-107
Genetic selection for carcass traits is paramount to maximize the profitability and long‐term sustainability of any meat‐producing livestock species. The main objectives of this research were to evaluate the efficiency of indicator traits for the genetic improvement of lamb carcass traits and to determine the value of including carcass traits into terminal sire selection indexes for the Canadian sheep industry. The carcass traits included hot carcass weight (HCW), fat depth at the GR site (FATGR) and average carcass conformation score (AVGCONF), and were measured on heavy lambs (slaughter age less than 365 days and HCW greater than 16.3 kg) in commercial abattoirs. Growth traits were found to be moderately efficient indicator traits for the genetic improvement of HCW but selection on ultrasound traits was necessary to substantially improve the carcass quality traits (FATGR and AVGCONF). Economic selection indexes were designed by adding various combinations of carcass traits into the Canadian Sheep Genetic Evaluation System terminal indexes. Records measured on individuals and progeny were assumed to be the sources of information for live animal and carcass traits, respectively. The changes in index accuracy, efficiency and expected correlated response were used to assess the value of their inclusion. HCW was found to have a large economic value, and its inclusion into terminal selection indexes was expected to substantially increase their accuracy (0.08–0.12 points) and efficiency (20%–30%). However, further including FATGR (measured 110 mm from the carcass midline over the 12th rib) and AVGCONF had little impact on the accuracy (≤0.03) and efficiency (1%–7%) of the proposed indexes. Thus, the inclusion of carcass traits into the existing terminal selection indexes could be beneficial for the genetic improvement of HCW, but further research is needed to determine optimal methods of increasing carcass fatness and muscularity. 相似文献
103.
文章就土地测绘的内涵解析作为切入点,浅要论述了土地测绘质量问题的影响因素,并就土地测绘质量问题影响因素的处理提出了一些浅薄的建议。以期促进我国土地测绘质量的提升。 相似文献
104.
针对面板数据灰色关联决策分析评价问题,在经典灰色关联分析和灰色综合评价方法的基础上,构建面板数据灰色关联决策评价模型。将灰色关联决策方法扩展到面板数据分析中,解决了小样本面板数据的灰色评价分析问题。将这种方法应用于水环境面板数据质量评价中,经实例计算验证了面板数据灰色关联决策评价模型的稳定性、合理性和实用性,为水环境面板数据质量分析评价提供了可行的计算思路和方法。 相似文献
105.
文章将会从优选原材料与质量控制体系,高性能混凝土配台比设计体系,钢筋保护层施工质量控制体系以及混凝土施工质量控制及反馈体系这四个方面分别加以阐述,希望能够得到一些借鉴和参考。 相似文献
106.
SHI Li-guang ZHOU Xiong XUN Wen-juan HOU Guan-yu ZHOU Han-lin HUANG Xian-zhou 《中国畜牧兽医》2016,43(1):101-107
This experiment was conducted to study the effect of selenium and vitamin E supplement on semen quality, antioxidant enzyme activities and heat shock protein expression of goat in Hainan high temperature season.16 adult Hainan Black goat with good health and approximate weight were randomly divided into 4 groups, fed with basal diet(control group), basal diet+0.5 mg/kg Se(Se group), basal diet+100 mg/kg VE(VE group), and basal diet+0.5 mg/kg Se+100 mg/kg VE(Se+VE group), respectively.The experimental period was 93 d.Semen samples were collected in the last week of the experiment on two consecutive days.The semen quality, antioxidant enzyme activities and heat shock protein expression were analyzed.The results showed that compared with control group, the ejaculate volume was not significantly affected by Se or VE supplement(P>0.05).Sperm density and sperm motility were increased significantly by Se and VE supplement(P<0.05), and the abnormal rate was decreased extremely significantly(P<0.01).The goats fed with Se and VE also had higher activities of GSH-Px(P<0.01), SOD(P<0.05), CAT(P<0.05) and T-AOC(P<0.01), and lower MDA concentration in seminal plasma(P<0.05).The relative expression levels of HSP70 and HSP90 mRNA in supplement groups were decreased extremely significantly(P<0.01).However, there were some certain differences between the Se and VE supplement groups on semen quality and heat shock protein expression.In conclusion, the supplementation of Se and VE could help to improve goat semen quality by increasing the sperm density, sperm motility, the antioxidant enzyme activities, and decreasing the abnormal rate in hot season of Hainan.Finally, Se and VE supplement had good effects on relieving the environment heat stress. 相似文献
107.
《The Journal of Applied Poultry Research》2016,25(3):370-378
The objective of this experiment was to evaluate the effects of dietary glutamine and glucose on pectoralis major meat quality in broilers under acute heat stress. Three hundred 35-day-old male broilers (Arbor Acres) were randomly divided into 5 groups. Broilers in the positive control group were kept in a thermoneutral environment (23 ± 1°C, RH 45%–55%) and fed a basic diet, whereas the experimental (2 × 2) group was exposed to acute heat stress (34 ± 1°C, RH 65%–75%) for 12 h and fed the basic diet that contained glutamine (0 and 10 g/kg) and glucose (0 and 10 g/kg). Compared with the positive control group, acute heat stress without glutamine and glucose supplementation increased (P < 0.05) drip loss, L* values, and AMPK concentrations, but it decreased (P < 0.05) water-holding capacity, moisture, pH, a* values, b* values, and glutamine concentrations in pectoralis major meat of chickens. However, dietary glutamine (10 g/kg) increased (P < 0.05) water-holding capacity, moisture, pH, a* values, b* values, and glutamine concentrations, while it decreased (P < 0.05) drip loss, L* values, and AMPK concentrations in heat-stressed chicken pectoralis major meat. Dietary glucose (10 g/kg) increased (P < 0.05) water-holding capacity, moisture, pH, and a* and b* values, while it decreased (P < 0.05) L* values and AMPK concentrations of pectoralis major meat in chickens exposed to acute high temperature. There were significant interactions between glutamine and glucose in the water-holding capacity, pH values, AMPK, and glutamine levels of pectoralis major meat in the heat-stressed chickens. The above results suggest that the addition of glutamine and glucose in the diet is necessary for broilers during acute heat stress condition. 相似文献
108.
为评价地熊蜂在重庆地区设施番茄的授粉效果,在重庆市荣昌区龙舌嘴村开展授粉效果比较试验,分析地熊蜂授粉对设施番茄产量、果实品质及畸形果率的影响。试验结果显示,经地熊蜂授粉的设施番茄平均产量为2 206.44 kg/667 m2,与未授粉组相比显著提高了104.95%,授粉组的单果质量、果纵径、果最大横径、可溶性固形物含量、VC含量及总糖含量显著高于未授粉组。由此,认为地熊蜂适宜为重庆地区设施番茄授粉,且能够显著提高重庆地区设施番茄的产量与品质。 相似文献
109.
110.