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Insights into Seasonal Dormancy of Perennial Herbaceous Forages 被引量:1
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作者 Laxman Adhikari Rasyidah M. Razar +2 位作者 Dev Paudel Ruyue Ding Ali M. Missaoui 《American Journal of Plant Sciences》 2017年第11期2650-2680,共31页
Seasonal dormancy is an adaptive mechanism where plants suspend growth and become physiologically inactive to avoid extreme environmental conditions. Environmental factors like temperature, photoperiod, nutrients, and... Seasonal dormancy is an adaptive mechanism where plants suspend growth and become physiologically inactive to avoid extreme environmental conditions. Environmental factors like temperature, photoperiod, nutrients, and soil moisture control plant growth and development through various complex molecular mechanisms. Crown and seed dormancy of plants are mostly influenced by day length and temperature. Genes and physiological pathways triggered by these two factors along with genotype variability are some targets to manipulate seasonal dormancy. There is genetic variation in the depth and duration of seasonal dormancy. Therefore, their genetic manipulation is possible. Manipulations of summer and fall dormancy are relatively easier compared to winter dormancy because plants require protection of their apical meristem from freezing temperatures and limited water supply. Genetic factors that regulate seed dormancy may also have regulatory role for seasonal dormancy of the maternal plants. Limited genetic and genomic information are available for seasonal dormancy in herbaceous perennial species. Knowledge of genes controlling seasonal dormancy of eudicots, forest trees, and horticultural crops could be interpolated to explore possible dormancy mechanisms in perennial forages. This study reviews current knowledge of seasonal dormancy of herbaceous forages emphasizing the genetic and physiological context that would be valuable to breeders and plant biologists to expand the production season of perennial species by developing non-dormant and semi-dormant cultivars. 展开更多
关键词 HERBACEOUS PERENNIALS SEASONAL DORMANCY Genes ENDODORMANCY forages Hormones
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Nitrogen recovery and agronomic efficiency of forages with nitrogen fertilization under flooded condition 被引量:1
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作者 Gilbert C. Sigua Mimi M. Williams +2 位作者 Chad C. Chase Jr. Janet Grabowski Manoch Kongchum 《Agricultural Sciences》 2013年第3期138-148,共11页
The cow-calf (Bos taurus) industry in subtropical United States and other parts of the world that depends almost totally on grazed pastures is facing several production constraints like changing climatic conditions an... The cow-calf (Bos taurus) industry in subtropical United States and other parts of the world that depends almost totally on grazed pastures is facing several production constraints like changing climatic conditions and increasing cost of fertilizers, especially nitrogen (N). Particularly little is known about the response of forage species to the combined effect of water-logging and the addition of N. A two-year greenhouse study was conducted in 2008 and 2009 to determine i) the effect of flooding duration on N recovery and agronomic efficiency of bahiagrass (Paspalum notatum Fluegge) compared with two flooding tolerant forages, limpograss (Hemarthria altissima Poir), and maidencane (Panicum hematomon Schult) and ii) if N fertilization could mitigate the negative effect of flooding. Nitrogen recovery and agronomic efficiency varied significantly (P ≤ 0.001) among forage species. Averaged across levels of N, N recovery of bahiagrass and limpograss was reduced by about 41% and 56%, respectively after 84 d of continued flooding while N recovery of maidencane was slightly increase by about 5% between 0 and 84 d of flooding. Agronomic efficiencies of bahiagrass (41% to 26%) and limpograss (44% to 31%) were reduced by flooding while agronomic efficiency of maidencane was increased from 24% (no flooding) to 46% at 84 d of continued flooding. However, N recovery and agronomic efficiency of three forage species was positively affected by N fertilization. The overall N recovery of bahiagrass, limpograss, and maidencane ranged from 44% to 59%. Nitrogen fertilization could improve N recovery and agronomic efficiency of forage species under waterlogged condition. 展开更多
关键词 forages NITROGEN RECOVERY AGRONOMIC Efficiency FLOODING NITROGEN
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Effects of Chemical Pretreatment on Enzymatic Saccharification and Fermentation of Forages
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作者 高凤芹 孙启忠 《Animal Husbandry and Feed Science》 CAS 2009年第3期19-23,共5页
[ Objective] To study the effect of pretreatment with chemical substances on enzymatic saccharification of affalfa ( Medic, ago sativa L. ), sorghum hybrid sudan grass [ Sorghum bicolor ( L. ) Moench x Sorghum sud... [ Objective] To study the effect of pretreatment with chemical substances on enzymatic saccharification of affalfa ( Medic, ago sativa L. ), sorghum hybrid sudan grass [ Sorghum bicolor ( L. ) Moench x Sorghum sudanese (Piper) Stapf], erect milkvetch (Astraga/us adsurgens Pall. ) and pearl millet ( Pennisetum americanum ( L. ) Leeke). [ Method ] The forages were pretreated with sulfuric acid at different concentration, and then the content of cellulose, hemicellulose, and lignin were detected and compared with that before pretreatment. The concentration of glucose and ethanol after different fermentation time was also determined. [ Result] After pretreatment, the content of cellulose increased, while that of hemicel- lulose and lignin decreased. After treatment with 1.0% (W/V) sulfuric acid, the four kinds of forages all had the highest concentration of ethanol in the citric acid-sodium citrate buffer system (pH 4.8). Dudng fermentation process, the concentration of glucose and ethanol first increased and then declined, peaking respectively at 24 h and 48 h post fermentation. [Condusion] Pretreatment promotes the enzymatic saccharification and fermen- tation of alfalfa, sorehum hvbrid sudan orass. Dead millet, and erect milkvetch, and their enerov performance decreases in order. 展开更多
关键词 PRETREATMENT FORAGE Cellulose ethanol Enzymatic saccharification and fermentation
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Photosynthesis Characteristics of Three Species of Forages in the Arid-Hot Valleys
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作者 YANG Yanxian LIAO Chengfei SHA Yucang PAN Zhixian FENG Guangheng JI Zhonghua 《Wuhan University Journal of Natural Sciences》 CAS 2008年第3期309-316,共8页
By using TPS-1 portable photosynthesis measuring system, the photosynthesis characteristics of three kinds of high quality forages used in the arid-hot valley eco-agricultural models in Yuanmou were measured. The pape... By using TPS-1 portable photosynthesis measuring system, the photosynthesis characteristics of three kinds of high quality forages used in the arid-hot valley eco-agricultural models in Yuanmou were measured. The paper shows that Pennisetum purpureum Schumach is the heliophilous shade tolerance C4 plant and Styiosanthes guianensis is the heliophilous shade tolerance plant, both of them could make full use of the light energy under the weak light environment and have relatively strong CO2 assimilation capacity. Cajanus cajan(L.) Millspaugh is the strong heliophilous plant with high requirement for light and has a relatively weak CO2 assimilation capacity. Generally, these three kinds of high quality forages are drought resistant and show a relatively good adaptability to the arid-hot valley environment. To improve cultivation administration level and to interplant timely in the forest can be helpful to the ecological niche and to improve the productivity force. 展开更多
关键词 forages PHOTOSYNTHESIS arid-hot valley
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Madagascar High Lands Dry Season Forages: Lofium multiflorum (Italian Ray Grass) and Avena sativa (Oat)
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作者 Isabelle Herisoa Hantanirina Olivier Jean Rakotonirina Rivo Nirina Rabearimisa Jean de Neupomuscene Rakotozandriny 《Journal of Environmental Science and Engineering(B)》 2014年第6期316-324,共9页
Italian ray grass and oat are two grass species characterized by their ability to adjust tropical climate conditions. This study proposed to assess forage productivities to allow an appropriate mowing period determina... Italian ray grass and oat are two grass species characterized by their ability to adjust tropical climate conditions. This study proposed to assess forage productivities to allow an appropriate mowing period determination in their use as dairy female feed in Madagascar. A test on small plots has been set up in the southern part of the capital city Antananarivo during one dry period (4 months). Live observations followed by laboratory proximate analyses have been performed for forage productivity and feeding value determination. Cultivated on tanety (hill), irrigated in counter season, results show that: (I) oat higher height (H = 96.7 cm) than Italian ray grass (H= 69.4 cm) at 99 days of age; (2) similar biomass productivity; (3) dry matter yields significantly different (p = 0.05); (4) certain similarity between dry matter yields and FMU (fodder milk unit) score evolution; (5) leafy stage of Italian ray grasses at 99 days of age; (6) mid-flowering stage for oats during the same period. Cell wall content, crude fiber and dry matter contents increased with age (p = 0.05). Crude proteins and minerals evolved in opposite directions. Gross energy content did not present precise variation with age. This study allowed that for an acceptable quantitative and qualitative production during dry seasons, good mowing period for Italian ray grass could start at 76 days age, while oat could start being harvested at 68 days. 展开更多
关键词 Counter season forages productivity feeding values Lolium multiflorum Avena sativa Madagascar.
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Diversity shifts of rumen bacteria induced by dietary forages in dairy cows and quantification of the changed bacteria using a new primer design strategy 被引量:2
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作者 JIN Di ZHAO Sheng-guo +4 位作者 ZHANG Yang-dong SUN Peng BU Deng-pan Yves Beckers WANG Jia-qi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第11期2596-2603,共8页
The partial 16 S r RNA gene sequences(100 to 500 bp) were widely used to reveal rumen bacterial composition influenced by diets, while quantification of the changed uncultured bacteria was inconvenient due to diffic... The partial 16 S r RNA gene sequences(100 to 500 bp) were widely used to reveal rumen bacterial composition influenced by diets, while quantification of the changed uncultured bacteria was inconvenient due to difficult designing of specific primers based on short sequences. This study evaluated the effect of forage resources on rumen bacterial diversity and developed new strategy for primer design based on short sequences to quantify the changed uncultured bacteria. Denaturing gradient gel electrophoresis(DGGE) analysis and subsequent band sequencing were used to reveal the distinct rumen bacteria composition in cows fed with two forage sources(single corn stover vs. mixed forages including alfalfa hay and corn silage). The bacterial diversity in the rumen of dairy cows fed with corn stover was lower than that with mixed forages(P0.05). The bacterium named R-UB affiliating to uncultured Succinivibrionaceae was identified, and it was abundant in the rumen of cows fed with mixed forages compared to corn stover. The full length 16 S r RNA gene sequences with identity of 97% to the R-UB 16 S r RNA gene sequence were obtained from Gen Bank and used to design specific primers to quantify uncultured bacterium R-UB. All sequences of amplicon from the new primers were of 100% identity to R-UB sequences indicating the high specificity of new primers. Quantitative PCR confirmed that abundance of R-UB in the rumen of cows fed with corn stover was lower than those fed with mixed forages(P0.01). New strategy for designing primers based on partial 16 S r RNA genes to quantify targeted uncultured bacteria was successfully developed. The rumen bacteria descending significantly in the cows fed corn stover compared to those fed mixed forages was identified as uncultured R-UB from Succinivibrionaceae. 展开更多
关键词 RUMEN bacterial diversity forage source PRIMERS qPCR
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Minerals profile of forages for grazing ruminants in Pakistan
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作者 Farhad Mirzaei 《Open Journal of Animal Sciences》 2012年第3期133-141,共9页
The current research was carried out at Rakh Khaire Wala, which is well known as one of the most developed animal husbandry in Punjab, Pakistan. This location in the arid region, where sheep farming is a common practi... The current research was carried out at Rakh Khaire Wala, which is well known as one of the most developed animal husbandry in Punjab, Pakistan. This location in the arid region, where sheep farming is a common practice, was selected for this study. The aim of the study was to determine and collect data on the mineral contents of forages or feedstuffs that are harvested and used in animal nutrition in the region, in order to gain information on the deficiency and/or excess of mineral levels for ruminants grazing therein, fed mainly with these feedstuffs. These pastures were visited twice during the study, in summer and winter, to collect samples in order to determine the effect of seasonal changes on the mineral contents of forages. In each location, samples from the available forages were collected. Forage samples were analyzed in order to determine the Ca, Mg, Na, K, Fe, Cu, Zn and Mn levels using an Atomic Absorption Spectrophotometer. These results show that pasture grasses/forages had sufficient levels of K, Ca, Mg, Mn and Zn to meet requirements of ruminant animals, but the occurrence of marginal to deficient supplies of Na, and Cu appear very likely. There is an urgent requirement for experimentation on supplementation regimes involving these minerals, so that appropriate recommendations can be formulated. 展开更多
关键词 MINERAL Composition FORAGE GRAZING Pakistan
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Control Effect of Replacement Cultivation of Several High Quality Forages against Eupatorium adenophorum
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作者 Hua Jingsong 《Plant Diseases and Pests》 CAS 2013年第5期26-28,32,共4页
[Objective] The paper was to analyze the control effect of replacement cultivation of several high quality forages against Eupatorium adenophorum. [ Method] Five high quality forages including Lolium perenne, Dactylis... [Objective] The paper was to analyze the control effect of replacement cultivation of several high quality forages against Eupatorium adenophorum. [ Method] Five high quality forages including Lolium perenne, Dactylis glomerata, Setaria anceps, Trifolium repens and Medicago sativa were planted in the fields invaded by E. adenophorum, and their ecological adaptability and control effect against E. adenophorum were studied. [Result] Five kinds of forages could nor- mally grow at the local land. The indexes such as coverage, plant height, fresh weight of stems and leaves of S. anceps were the highest, and it showed very strong ecological adaptability as well as the best control effect on E. adenophorum, up to 97.85% and 93.81% at the first and second year, respectively, indicating good sustainable control effect. D. glomerata ranked the second place, of which the coverage after one year was 86% and the control effect on E. adenophorum was 89.68%. The other species showed poor control effect on E. adenophorum because of slow growth rate and heavily damage from companion weeds even they could establish dominant communities. [ Condusion] The paper provided reference for ecological control against E. adenophorum in local land and ecological restoration of invasive land. 展开更多
关键词 Eupatorium adenophorum High quality forage Replacement control
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Effect of Dehydrated Digested Effluent of Manure on Yield and Quality of Annual Forages and Soil Chemical Properties in Southern Kyushu, Japan
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作者 Sachiko Idota Yasuyuki Ishii 《Agricultural Sciences》 2014年第10期843-849,共7页
Digested effluent of manure (DEM) produced by biogas-plants contains many macro- and micro-nutrients. In an experiment conducted in southern Kyushu (Japan), forage crops cultivated after receiving DEM and chemical fer... Digested effluent of manure (DEM) produced by biogas-plants contains many macro- and micro-nutrients. In an experiment conducted in southern Kyushu (Japan), forage crops cultivated after receiving DEM and chemical fertilizers exhibited similar dry matter yields. From a logistical standpoint, however, DEM in liquid form is difficult to handle and apply due to the low concentration of nutrients. To overcome this shortcoming, we prepared dehydrated DEM (DDEM) by adding DEM to cattle manure without disturbing the manure fermentation process. The objective of this research was to evaluate the effect of DDEM on dry matter yield and nitrogen recovery rate in annual dual-cropping systems (summer crop of maize or sorghum and winter crop of Italian ryegrass) that are typical of the region and to compare these results to commercial cattle manure alone, in combination with chemical fertilizer (CM or CM + CF), or no fertilizer application (NF). In both cropping systems, the DDEM treatment produced similar dry matter yields (2.6 to 3.02 kg&middotm-2) and apparent nitrogen recovery rates (43% to 53%) as the CM + CF and CM treatments. This suggests that DDEM can potentially replace chemical fertilizers and commercial cattle manure in the region. 展开更多
关键词 Digested Effluent of MANURE ANNUAL FORAGE Nitrogen Recovery Yield
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Exploration of concentration of two macro-minerals in different wild forages in relation to nutrient requirements of livestock
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作者 Kafeel Ahmad Zafar Iqbal Khan +5 位作者 Muneeba Shaheen Farhad Mirzaei Abrar Hussain Fahim Arshad Tahir Mehmood Zahara Bibi 《Agricultural Sciences》 2013年第7期340-344,共5页
The composition of two macro-minerals (Ca and Na) was examined in soil and forages in two fields of District Sargodha, Pakistan. During winter and summer season, soil and forage samples were collected. In both seasons... The composition of two macro-minerals (Ca and Na) was examined in soil and forages in two fields of District Sargodha, Pakistan. During winter and summer season, soil and forage samples were collected. In both seasons, Na was sufficient in soil and forages. As compared to the winter season, the Na and Ca levels in soil were considerably higher in summer season. In forages, the level of Ca was deficient than the level which is essential for livestock growth. In the pastures, grazing livestock may be?deficient in these minerals as these pastures are not supplying sufficient minerals to the ruminants grazing therein. Supplementation of minerals is necessary to prevent the mineral imbalances and deficiency diseases in grazing livestock. 展开更多
关键词 MINERAL Composition Soil FORAGE LIVESTOCK
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Nickel, lead and manganese content of forages irrigated with different sewage water treatments: A case study of a semiarid region (Sargodha) in Pakistan
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作者 Kafeel Ahmad Zafar Iqbal Khan +5 位作者 Yasir Rizwan Muhammad Sher Muhammad Khalid Mukhtar Rab Nawaz Muneeba Shaheen Farhad Mirzaei 《Agricultural Sciences》 2013年第4期180-184,共5页
The use of sewage water for agricultural purpose has tremendously increased during the last few years due to shortage of water availability, especially in semi-arid regions. Despite of many nutrients recycling advanta... The use of sewage water for agricultural purpose has tremendously increased during the last few years due to shortage of water availability, especially in semi-arid regions. Despite of many nutrients recycling advantages of sewage water, farmers are not fully aware of its harmful chemical composition. Heavy metals toxicity in soil and crops results from the long term use of sewage effluent for irrigation purposes. The present study was conducted to assess effect of sewage water on the uptake of Ni, Pb and Mn in different forage species with respect to the nutrient requirement of the grazing ruminants inSargodha,Punjab,Pakistan. Five samples each of six fodder species viz., Trifolium alexandrinum, Cichorium intybus, Avena sativa, Medicago polymorpha, Brassica campestris and Medicago sativa were collected from three fields irrigated with canal water, mix water (canal plus sewage water) and sewage water respectively. Pb, Ni and Mn concentration in the forage species during different treatments varied from 0.624 to1.672 mg/g, 7.364 to 10.17 mg/g and 5.136 to 12.422 mg/kg respectively. High value of Pb and Mn concentrations was observed during sewage water treatment. Lead is a non-essential element and is a very toxic metal. But in the present investigation Ni and Pb level in forages were below the toxic level, so the ruminants feeding on these forage species had no chance of Pb and Ni toxicity. On the other hand, Mn concentration in the forage species under observation was below the critical level. So the grazing animals at this location need continued mineral supplementation of Mn to prevent diseases caused by Mn deficiency, and to support optimum animal productivity. The objective of this study was to examine the potential for forage analysis as indicators of likely mineral deficiencies or excesses of grazing livestock during different sewage water treatments. 展开更多
关键词 SEWAGE Water NICKEL LEAD Soil FORAGE Pakistan
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Use of Ultrasound Bath in the Extraction and Quantification of Ester-Linked Phenolic Acids in Tropical Forages
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作者 Mellina Damasceno Rachid Santos Aline de Paula Vitor +3 位作者 Jailton da Costa Carneiro Domingos Savio Campos Paciullo Renato Camargo Matos Maria Auxiliadora Costa Matos 《American Journal of Analytical Chemistry》 2011年第3期344-351,共8页
A method was developed for the analysis of ester-linked phenolic acids in forage samples using extraction by an ultrasound-assisted treatment and quantification by HPLC with a UV-VIS detector. A reversed-phase C18 col... A method was developed for the analysis of ester-linked phenolic acids in forage samples using extraction by an ultrasound-assisted treatment and quantification by HPLC with a UV-VIS detector. A reversed-phase C18 column was used for developing the method and the optimal condition was established with isocratic elution using acetonitrile/methanol/H3PO4 pH 2.08 (13:12.5:74.5) as the mobile phase. To reduce the time of sample processing, the extraction of ester-linked phenolic acids was studied using ultrasound bath and the results were then compared with those from an extraction usual using alkaline hydrolysis (20°C for 24 h). The method was valued through external and internal calibration. Internal calibration using o-coumaric acid as internal standard and m-coumaric acid as surrogate internal standard showed better results. The detection limits were of 0.09 and 0.04 mg●L-1 for p-coumaric and ferulic acids, respectively. The proposed method showed a good linear dynamic range (3.00 - 30.00 mg●L-1) for the analytes. The usefulness of the methodology was demonstrated by addition-recovery experiments using forage samples and values were in the 83 to 99% range. The extraction of ester-linked phenolic acids by 120 minutes of ultrasound bath was faster and more reproducible than alkaline hydrolysis (20°C for 24 h). 展开更多
关键词 Ultrasound Bath Phenolic Acids FORAGE Internal Calibration
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Nutritive value of forages consumed by ruminants during the dry season in the Western Highlands of Cameroon
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作者 Leslie Tieubou Tsopgni Jules Lemoufouet +5 位作者 Felix Meutchieye Langston Wilfried Edie Nounamo Camile Nyembo Kondo Jean Raphaël Kana Mama Mouchili Back Armel Feudjio 《Grassland Research》 2023年第2期112-119,共8页
Background:In the Western Highlands of Cameroon(WHC),information on the nutritional value of fodder species consumed by ruminants is very limited.Methods:Through interviews with farmers and monitoring of animals on th... Background:In the Western Highlands of Cameroon(WHC),information on the nutritional value of fodder species consumed by ruminants is very limited.Methods:Through interviews with farmers and monitoring of animals on the range,information was obtained on the types of fodder resources consumed by the ruminants.Samples of each forage species were collected in 15 districts,mixed,chopped,and dried in a ventilated oven at 60°C,and then ground for chemical composition analysis.Results:Twenty-two forage species were identified.Among these species,Vernonia amygdalina(29.43%±0.45%dry matter[DM])and Pennisetum clandestinum(87.21%±1.33%DM)were,respectively,the highest in protein and neutral detergent fiber contents.Manihot esculenta was one of the most energy-rich forages in terms of forage unit for lactation and forage unit for meat production.Hierarchical ascending classification revealed three main groups of forages,respectively,rich in crude fiber(Group 1),protein(Group 2),and energy(Group 3).Conclusions:The present study identified 22 forage species browsed by ruminants in WHC.Further studies should be carried out to determine the antinutritional factors and to evaluate their nutrient value using in vitro or in situ digestibility techniques. 展开更多
关键词 chemical composition nutritional value RUMINANTS tropical forages Western Highlands of Cameroon
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Ruminal fermentation and microbial community differently influenced by four typical subtropical forages in vitro 被引量:6
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作者 Muhammad W.Iqbal Qin Zhang +5 位作者 Yingbai Yang Caixia Zou Lili Li Xin Liang Shengju Wei Bo Lin 《Animal Nutrition》 SCIE 2018年第1期100-108,共9页
The present study evaluated the effects of 4 typical subtropical forages on ruminal microbial community composition to formulate a better diet for buffalo.Corn straw silage,elephant grass,cassava residues and sugarcan... The present study evaluated the effects of 4 typical subtropical forages on ruminal microbial community composition to formulate a better diet for buffalo.Corn straw silage,elephant grass,cassava residues and sugarcane tail silage were used as substrates for in vitro fermentation.Eight replicates were set up for every substrate,and fermentation was carried out in a 100-m L glass syringe,using buffalo rumen inoculum.Every replicate was anaerobically dispensed with 10 m L of rumen inoculum,20 m L of Mc Dougall's buffer and 200 mg of dried substrate,and placed in a water bath at 39C.Gas production was recorded at 0,2,6,12,24,36,48 and 72 h of incubation.After 24 h,fermentation was ceased for 4 replicates and samples were collected.Volatile fatty acids(VFA) concentrations were measured using gas chromatography.Microbial populations were quantified using quantitative real-time PCR(q RT-PCR),and microbial community was analyzed using high throughput sequencing technology.The results showed,cassava residues as substrate had the highest gas production,acetate,propionate and total VFA concentrations(P < 0.05),and corn straw silage had the lowest acetate:propionate ratio(P < 0.05).The lowest numbers of fungi,Ruminococcus albus and Fibrobacter succinogenes,and the highest number of protozoa were observed with cassava residues(P < 0.05).The least abundances of bacterial phyla Firmicutes,Bacteroidetes and genus Prevotella,and substantially higher abundance of phylum proteobacteria(56%) and genus Succinivibrio(52%) were observed with cassava residues.The most abundances of Methanobrevibacter gottschalkii and Entodinium were observed with cassava residues.Spearman's correlations analysis showed,Succinivibrio had strong positive correlations with propionate,butyrate,Metadinium and M.gottschalkii,indicating fermentation products were related to microbial community.In conclusion,incubation with cassava residues resulted in lower number of fiber degrading microbes but higher protozoal population because of its low fiber contents.The microbial community was highly altered by in vitro incubation with cassava residues,whereas remained similar for the other 3 high fiber containing substrates. 展开更多
关键词 Buffalo rumen inoculum In vitro fermentation Subtropical forages Microbial population Microbial community
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No evidence of predator odor avoidance in a North American bird community
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作者 Austin Dotta Batur Yaman Alex Van Huynh 《Avian Research》 SCIE CSCD 2024年第1期133-138,共6页
Recent advances in our understanding of avian chemical communication have highlighted the importance of olfaction in many aspects of avian life.Prior studies investigating predator avoidance behaviors in response to p... Recent advances in our understanding of avian chemical communication have highlighted the importance of olfaction in many aspects of avian life.Prior studies investigating predator avoidance behaviors in response to predator odor cues have produced mixed results across species and contexts.Here we assess if a community of birds in eastern Pennsylvania displays avoidance behaviors towards predator odor cues in a natural foraging setting.We use clay caterpillars to measure foraging activity by birds in the presence of predator(bobcat)urine,non-predator(rabbit)urine,and water controls in two different environmental contexts(field vs.forest).Although we detected a weak trend for birds to forage less at predator urine-treated sites,we found no significant difference in avian foraging between the site types.We did find that foraging rates between environmental contexts changed significantly over the course of the experiment,with forest sites showing decreasing foraging rates and field sites showing increasing foraging rates.Our results reinforce the published literature that avoidance of predator odors by birds may not be ubiquitous across contexts and species. 展开更多
关键词 FORAGING ODOR OLFACTION PREDATION Predator-avoidance
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Distributional and behavioral responses of the wintering Oriental Storks to drought in China’s largest freshwater lake
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作者 Fucheng Yang Mingqin Shao Jianying Wang 《Avian Research》 SCIE CSCD 2024年第2期187-195,共9页
Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi... Extreme droughts are increasing in frequency and severity globally as a result of climate change.Developing understanding of species’responses to drought is crucial for their conservation,especially in regions experi-encing increased aridity.Although numerous studies have investigated birds’responses to drought,the emphasis has primarily been on landbirds.Drought can significantly alter the wetland environments that waterbirds inhabit,but the response of waterbirds to drought remains understudied.In this study,we surveyed the distri-bution and behavior of Oriental Storks(Ciconia boyciana)in Poyang Lake,which is the largest freshwater lake in China.Results indicate that drought-induced catchment areas at the lowest water level limited the total popu-lation size of Oriental Storks in the sub-lakes.Sub-lakes with large catchment areas at the lowest water level demonstrated a capacity to support a larger population of wintering Oriental Storks.Over time,Oriental Storks exhibited a gradual concentration in Changhu Lake,characterized by larger catchments,after resource depletion in sub-lakes with smaller catchments.Additionally,the duration of Oriental Storks’vigilance and moving be-haviors decreased significantly compared with that observed before the drought.After the drought,Oriental Storks increased their foraging efforts,as evidenced by increased presence in deeper water and reaching their heads and necks into deeper water to forage,higher search rates,but lower foraging rates.In accordance with area-restricted search theory,reductions in habitat quality resulting from drought,including extensive fish die-offs,forced Oriental Storks to increase their foraging efforts.Sustaining a specific water area in sub-lakes during droughts can preserve resource availability,which is crucial for the conservation of Oriental Storks.Imple-menting measures such as water level control and micro-modification of lake bottoms in sub-lakes might mitigate the impact of drought on the piscivorous Oriental Storks. 展开更多
关键词 Climate change Extreme drought Foraging behavior Oriental stork Poyang lake
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Spatial search weighting information contained in cell velocity distribution
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作者 马一凯 李娜 陈唯 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期522-528,共7页
Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell ... Cell migration plays a significant role in physiological and pathological processes.Understanding the characteristics of cell movement is crucial for comprehending biological processes such as cell functionality,cell migration,and cell–cell interactions.One of the fundamental characteristics of cell movement is the specific distribution of cell speed,containing valuable information that still requires comprehensive understanding.This article investigates the distribution of mean velocities along cell trajectories,with a focus on optimizing the efficiency of cell food search in the context of the entire colony.We confirm that the specific velocity distribution in the experiments corresponds to an optimal search efficiency when spatial weighting is considered.The simulation results indicate that the distribution of average velocity does not align with the optimal search efficiency when employing average spatial weighting.However,when considering the distribution of central spatial weighting,the specific velocity distribution in the experiment is shown to correspond to the optimal search efficiency.Our simulations reveal that for any given distribution of average velocity,a specific central spatial weighting can be identified among the possible central spatial weighting that aligns with the optimal search strategy.Additionally,our work presents a method for determining the spatial weights embedded in the velocity distribution of cell movement.Our results have provided new avenues for further investigation of significant topics,such as relationship between cell behavior and environmental conditions throughout their evolutionary history,and how cells achieve collective cooperation through cell-cell communication. 展开更多
关键词 cell migration foraging efficiency random walk spatial search weight
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Diverse foraging strategies of breeding Swinhoe's Storm-petrel in the productive marginal sea of the Northwest Pacific
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作者 Yachang Cheng Lei Zhu +6 位作者 Lin Xue Shisheng Ma Nan Jia Shaoping Zang Zhihai Cao Jing Yuan Yang Liu 《Avian Research》 SCIE CSCD 2024年第1期27-34,共8页
Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to... Understanding the foraging behavior is essential for investigating seabird ecology and conservation,as well as monitoring the well-being of the marine environment.Breeding seabirds adopt diverse foraging strategies to maximize energy gains and cope with the intensified challenges of parenting and self-maintenance.Such tradeoff may stem from the heterogeneity of food resources and the constraints of central place foraging.Nevertheless,abundant marine productivity could alleviate the energy limitation for seabirds,resulting in a consistent foraging approach.Here,we investigated the foraging strategy during the breeding season of a cryptic small-sized seabird,Swinhoe’s Storm-petrel(Hydrobates monorhis),in the Yellow Sea,a productive marginal sea of the Northwest Pacific.Using GPS tracking,we evaluated habitat preference,quantified the foraging strategy,and tested if environmental conditions and individual traits influence foraging trips.We found that Swinhoe’s Storm-petrels preferred nearshore areas with shallow water and engaged in primarily short foraging trips.Distinctive southeastward and southwestward strategies emerged when combining trip metrics,including foraging direction,duration,and maximum distance.The bathymetry,proximity to the coastline,and sea surface temperature differed in two foraging strategies.Foraging strategies exhibited flexibility between individuals,potentially explained by wing morphology,in which longer-winged birds are more likely to embark on longer-distance foraging trips.These findings highlight the impact of environmental factors and individual traits on seabirds’foraging decisions in productive marginal sea ecosystems.Our study also provides valuable insights into the foraging ecology of this Asian endemic storm-petrel. 展开更多
关键词 Behavioral strategy BIOLOGGING Central place foraging Marine primary productivity Seabird Sea surface temperature
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Metaheuristic-Driven Two-Stage Ensemble Deep Learning for Lung/Colon Cancer Classification
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作者 Pouyan Razmjouei Elaheh Moharamkhani +2 位作者 Mohamad Hasanvand Maryam Daneshfar Mohammad Shokouhifar 《Computers, Materials & Continua》 SCIE EI 2024年第9期3855-3880,共26页
This study investigates the application of deep learning,ensemble learning,metaheuristic optimization,and image processing techniques for detecting lung and colon cancers,aiming to enhance treatment efficacy and impro... This study investigates the application of deep learning,ensemble learning,metaheuristic optimization,and image processing techniques for detecting lung and colon cancers,aiming to enhance treatment efficacy and improve survival rates.We introduce a metaheuristic-driven two-stage ensemble deep learning model for efficient lung/colon cancer classification.The diagnosis of lung and colon cancers is attempted using several unique indicators by different versions of deep Convolutional Neural Networks(CNNs)in feature extraction and model constructions,and utilizing the power of various Machine Learning(ML)algorithms for final classification.Specifically,we consider different scenarios consisting of two-class colon cancer,three-class lung cancer,and fiveclass combined lung/colon cancer to conduct feature extraction using four CNNs.These extracted features are then integrated to create a comprehensive feature set.In the next step,the optimization of the feature selection is conducted using a metaheuristic algorithm based on the Electric Eel Foraging Optimization(EEFO).This optimized feature subset is subsequently employed in various ML algorithms to determine the most effective ones through a rigorous evaluation process.The top-performing algorithms are refined using the High-Performance Filter(HPF)and integrated into an ensemble learning framework employing weighted averaging.Our findings indicate that the proposed ensemble learning model significantly surpasses existing methods in classification accuracy across all datasets,achieving accuracies of 99.85%for the two-class,98.70%for the three-class,and 98.96%for the five-class datasets. 展开更多
关键词 Lung cancer colon cancer feature selection electric eel foraging optimization deep learning ensemble learning
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Dispersed Wind Power Planning Method Considering Network Loss Correction with Cold Weather
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作者 Hanpeng Kou Tianlong Bu +2 位作者 Leer Mao Yihong Jiao Chunming Liu 《Energy Engineering》 EI 2024年第4期1027-1048,共22页
In order to play a positive role of decentralised wind power on-grid for voltage stability improvement and loss reduction of distribution network,a multi-objective two-stage decentralised wind power planning method is... In order to play a positive role of decentralised wind power on-grid for voltage stability improvement and loss reduction of distribution network,a multi-objective two-stage decentralised wind power planning method is proposed in the paper,which takes into account the network loss correction for the extreme cold region.Firstly,an electro-thermal model is introduced to reflect the effect of temperature on conductor resistance and to correct the results of active network loss calculation;secondly,a two-stage multi-objective two-stage decentralised wind power siting and capacity allocation and reactive voltage optimisation control model is constructed to take account of the network loss correction,and the multi-objective multi-planning model is established in the first stage to consider the whole-life cycle investment cost of WTGs,the system operating cost and the voltage quality of power supply,and the multi-objective planning model is established in the second stage.planning model,and the second stage further develops the reactive voltage control strategy of WTGs on this basis,and obtains the distribution network loss reduction method based on WTG siting and capacity allocation and reactive power control strategy.Finally,the optimal configuration scheme is solved by the manta ray foraging optimisation(MRFO)algorithm,and the loss of each branch line and bus loss of the distribution network before and after the adoption of this loss reduction method is calculated by taking the IEEE33 distribution system as an example,which verifies the practicability and validity of the proposed method,and provides a reference introduction for decision-making for the distributed energy planning of the distribution network. 展开更多
关键词 Decentralised wind power network loss correction siting and capacity determination reactive voltage control two-stage model manta ray foraging optimisation algorithm
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