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1.
Effect of Mediterranean saltbush (Atriplex halimus) ensilaging with two developed enzyme cocktails on feed intake,nutrient digestibility and ruminal fermentation in sheep 下载免费PDF全文
Haidy Alsersy Abdelfattah Z. M. Salem Borhami E. Borhami Jaime Olivares Hany M. Gado Maria D. Mariezcurrena Mohamed H. Yacuot Ahmed E. Kholif Mounir El‐Adawy Saul R. Hernandez 《Animal Science Journal》2015,86(1):51-58
The aim of this study was to assess the effects of feeding Atriplex halimus (AH) silage treated with two developed enzyme cocktails to sheep on feed intake, nutrient digestibility and ruminal fermentation. The AH silage was treated without or with 2 L of ZAD1® or ZAD2®/1000 kg with 5% molasses and ensiled for 30 days. Barley grain (300 g/head/day) was fed as an energy supplement once daily at 10.00 hours and AH silage with or without enzyme treatment was offered ad libitum to animals twice daily at 09.00 and 16.00 hours. Sheep were fed on four experimental forage diets comprised of AH silage and barley (D1), AH silage treated with ZAD1® and barley (D2), AH silage treated with ZAD2® and barley (D3) and AH silage treated with a combination of ZAD1® and ZAD2® (1:1) and barley (D4). Ensiling AH with enzymes reduced its contents of neutral detergent fiber and acid detergent fiber. The dry matter intake of AH of D2, D3 and D4 decreased (P < 0.001) as compared to D1. However, enzyme‐treated diets had greater total digestible nutrients intake (P < 0.001) as compared to D1. The nutrients digestibility for D2, D3 and D4 were higher than those for D1 (P < 0.001), and were higher for D3 as compared to both D2 and D4. Sheep fed on D3 had highest (P < 0.001) ruminal total volatile fatty acids concentration, ammonia nitrogen concentration and microbial protein yield. It could be concluded that AH silage treated with ZAD1® or ZAD2® improved digestibility and rumen fermentation in sheep. 相似文献
2.
在气候干燥、寒冷的西北地区 ,引进具有耐干旱、贫瘠 ,抗寒冷 ,抗盐碱等多种优良特性的常绿或准常绿饲料灌木四翅滨藜 ,经过 2a生长全过程的栽培试验 ,观测结果表明 :在不同土壤类型下 ,新梢生长量、扦插育苗的成活率、保存率都表现出差异性。但移栽苗的成活率、保存率差异不大 ,表现出较强的适应性。而在中、强盐碱性土壤、(粗 )砂土中仍能正常生长 ,但新梢生长量低 ,分枝减少 相似文献
3.
Based on polyacrylamide gel electrophoresis, nine natural populations of Atriplex halimus L., a perennial shrub, collected in different regions of Morocco, were studied for their genetic variation using isoenzyme
polymorphism of the highly active enzyme systems: esterases (EST), acid phosphatases (ACP) and glutamate oxaloacetate transaminase
(GOT). Different allozyme frequencies from 7 different loci were obtained for all populations of this halophyte species. High
levels of genetic diversity were revealed. The mean number of alleles per locus (A = 1.9–2.0), the percentage of polymorphic
loci (p = 71.4–85.7) and the mean expected heterozygosity (He = 0.339–0.385) showed an important variability in all populations. Gene diversity was essentially explained by the within
population component. The between populations differentiation accounted for 8% of the whole diversity (FST, averaged over all loci, is 0.08). The relationships among the 9 populations were inferred from the Nei’s genetic distances.
Four major groups were formed. The northern population ‘Tanger’, forming a unique group, was highly divergent from the other
groups. It appeared that the genetic distance between all groups was related to the geographic distance that separates them.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
Hayley C. Norman Matt G. Wilmot Dean T. Thomas David G. Masters Dean K. Revell 《Livestock Science》2009,121(2-3):162-172
The stable carbon isotope technique has been widely used to infer the dietary ecology of a range of animal species; however calibration of the technique with animals fed known diets is essential for accurate back-calculation of dietary preferences. The aim of this study was to identify suitable samples and back-calculation methods to predict short-term (2 to 3 week) dietary selection by sheep among plants with C3 and C4 photosynthetic pathways. Variation in integration time of dietary carbon into plasma and faeces; diet-tissue discrimination of carbon isotopes (fractionation) and the importance of accounting for the digestible or indigestible components of the diet was investigated. The results indicate that faecal and rumen samples provided the most accurate prediction of short term dietary changes in sheep selecting between C3 and C4 plants. The most accurate back-calculation method for these samples used δ13C of the C3 and C4 plants and accounted for both diet-tissue discrimination and differences in the indigestibility between the C3 and C4 forage. For faecal samples, the organic matter content of the diet originating from C4 plants could be predicted with a mean error as low as 2.7%. Wool and plasma samples were not conducive to predicting proportion of C4 forage in the diet within 18 days after a change in diet; however plasma could be used to discriminate between animals fed 100% C3 and C4 diets after 3 days. The δ13C technique provides a valuable tool for researchers when designing pastures for dual environmental and production purposes. An understanding of what sheep select allows for development of appropriate grazing management strategies to optimise productivity and/or persistence of target species. 相似文献
5.
三角叶滨藜甜菜碱醛脱氢酶基因克隆及植物表达载体的构建 总被引:2,自引:1,他引:2
通过RT PCR技术从盐生植物三角叶滨藜总RNA中,扩增并克隆了BADH68基因。该基因全序列显示,核苷酸序列长1520bp,12~1515bp为1个开放阅读框架,推测的氨基酸序列全长为500个氨基酸残基,其核苷酸序列与菠菜和山菠菜同源性分别为89%和95%。利用BamHI和SacI酶切位点将BADH68基因连接到pCAMBI A2301的多克隆位点,并把35S启动子和nos终止子分别连接到BADH基因的上游和下游的多克隆位点上,获重组植物表达质粒pCAMATBADH682,并转入根癌农杆菌LBA4404中,获LBA4404(pCBAMATBADH682)菌种。 相似文献
6.
7.
3种灌木幼苗对干旱胁迫的生理响应 总被引:1,自引:0,他引:1
通过盆栽试验测定了土壤自然干旱胁迫过程中柽柳、梭梭和四翅滨藜3种灌木叶片相对含水量、水分饱和亏、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性和脯氨酸含量的变化,研究了3种植物对水分胁迫逆境环境的生理适应机理.结果表明:随土壤水分胁迫的加重,3种灌木叶片相对含水量下降,水分饱和亏增加,渗透调节物质脯氨酸积累,保护酶系统酶活性上升,但在变化趋势和幅度上有显著差异.3种灌木幼苗均有较强的耐旱性,但耐旱机制不同. 相似文献
8.
该文阐述了以四翅滨藜1a生茎段为实验材料,比较研究了不同的基本培养基对四翅滨藜茎段的离体培养的诱导效果,通过正交试验结果认为,四翅滨藜最佳的初代培养基为MS+BA0.5+NAA 0.05。 相似文献
9.
采用室内模拟大田的试验方法,以引进大洋洲滨藜为试材,研究不同浓度的碱性盐NaHCO3胁迫下生物量、叶绿素含量、光合参数、Na+、K+、Ca2+等离子的动态变化。结果表明,随着NaHCO3胁迫浓度的升高,生物量、叶绿素质量分数、叶绿素a/叶绿素b的比值、净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(Gs)呈现先升后降的趋势,即低浓度(150mmol·L-1)时最高,胞间CO2体积分数(Ci)呈现先降后升的趋势,Na+、Na+/K+的比值和Na+/Ca2+的比值呈现升高趋势,K+、Ca2+呈现降低趋势;随着时间的变化,14d时大洋洲滨藜生长状况最好;在300mmol·L-1胁迫下,加入脱硫废弃物后,生物量、叶绿素质量分数、叶绿素a/叶绿素b的值、Pn、Tr、Gs、K+和Ca2+质量分数等均高于处理。说明大洋洲滨藜在低浓度时(150mmol·L-1)较适宜生长;同时也说明脱硫废弃物在一定程度上可减缓碱胁迫对大洋洲滨藜的伤害。 相似文献
10.
Márcio Fléquisson Alves Miranda Maria Betânia Galvão dos Santos Freire Brivaldo Gomes Almeida Fernando José Freire Luiz Guilherme Medeiros Pessoa 《Archives of Agronomy and Soil Science》2018,64(9):1207-1221
This study aimed to evaluate the use of phytoremediation and soil conditioners in the recovery of physical attributes of a saline-sodic Fluvic Neossol in Brazil Northeast. The applied treatments were: Atriplex nummularia L., as phytoremediation plant, due to its ability to extract salts from the soil; organic conditioners, such as bovine and sheep manure; gypsum and polymer, as chemical conditioners. Samples with preserved structure were collected at the time of the experiment installation and 18 months after in the layers 0–10 cm and 10–30 cm. The analyzed attributes were: water dispersed clay, dispersion index, bulk density, penetration resistance, soil porosity, and saturated hydraulic conductivity. The use of sheep manure, gypsum and polymer promoted an increase in saturated hydraulic conductivity in the 0–10 cm layer from 4.51 to 16.37 cm day?1, 11.26 to 23.95 cm day?1 and 7.24 to 22.77 cm day?1, respectively. Gypsum increased the macroporosity in the superficial layer by 42.6%. Atriplex and polymer were more efficient at reducing soil penetration resistance. The polymer was more efficient at improving the physical properties. However, it is necessary to consider phytoremediation with Atriplex as a more sustainable alternative that can still be used as complementary fodder in animal feed. 相似文献