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Alyce Raiana Monteiro dos Santos Lívia Vieira de Barros Matheus Lima Côrrea Abreu Bruno C. Pedreira 《Grass and Forage Science》2020,75(3):339-350
The addition of protein supplementation in a silvopastoral system can contribute to improved forage intake and digestibility. Our objective was to evaluate in vitro ruminal parameters, digestibility and gas production of Marandu palisadegrass [Urochloa brizantha (Hochst. ex A. Rich.) R. D. Webster] in a silvopastoral system and compare this to parameters obtained from diets with protein supplementation. Forage was sampled during the growing season (November to April) in 2016/17 and 2017/18. In vitro incubation treatments consisted of four levels of protein supplement (20% of crude protein; CP) in the diet (0.1, 0.2, 0.3 and 0.4 g/kg of body weight). The neutral detergent fibre, acid detergent fibre and indigestible neutral detergent fibre concentrations were highest in the first year. In the second year, CP concentration was 21% greater than in the first year. There was a linear increase for digestion rate, a quadratic effect for lag time and a linear decrease for average digestion time as supplementation levels were increased. The least lag time and digestion time occurred in the second year. There was no supplementation effect on ruminal pH, acetate and butyrate concentrations. Second-year in vitro dry matter digestibility (IVDMD) was greater than in the first year. Increases in supplementation levels linearly enhanced IVDMD and reduced methane (CH4) production. The inclusion of a protein supplement contributed to reduced CH4 and increased volatile fatty acids production; therefore, we recommended the supplement inclusion of >0.28 g/kg of BW for animals grazing in well-managed palisadegrass pastures. 相似文献
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1991年从哥伦比亚国际热带农业研究中心(CIAT)引入6095刚果臂形草(Brachiaria ruziziensis G.et E.CIAT6095),1992-1993年在网室和田间进行生态适应性观测,1994-1996年进行品种比较试验,1999-2004年进行区域试验,1999-2005年在海南、云南和福建进行生产试验。结果表明:热研15号刚果臂形草产草量达209865.83 kg/hm2·a,极显著(P<0.01)高于热研6号珊状臂形草(B.brizantha cv.Reyan 6)54.43%,高于热研3号俯仰臂形草(B.decumbens cv.Reyan 3)43.76%;热研15号刚果臂形草喜湿润热带气候,适宜在海拔1000~2000 m,年降水1000 mm以上的热带、亚热带地区生长,具有良好的耐旱能力,在pH4.5~5.0和极端贫瘠的土壤具有良好的持久性和丰产性;适于建植高产、优质、耐久的放牧型草地;固土护坡能力强,适于作水土保持的先锋草种。 相似文献
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Four clones of palisade grass, Brachiaria brizantha (Hochst. Ex. A. Rich.) Stapf., were studied in a diallel competition trial to investigate their competitive relationship in clonal mixtures. Clone X associate interactions were observed for plant height, number of tillers per plant and dry matter yield per plant. Both general and specific competitive abilities were observed for tiller number and dry matter yield. Clone X associate interaction for plant height was mainly due to the specific competitive ability of individual combinations. The most competitive clone observed was CIAT 6387. Competitive abilities of local clones were low compared to the imported clones. Local clones (RU 127 and RU 139) yielded more than imported clones (CIAT 6387 and PI 292185) under low competitive stresses. General and specific competitive abilities should be taken into consideration when mixing clones of palisade grass. 相似文献
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Fingerprinting of alfalfa meiotic mutants using RAPD markers 总被引:5,自引:0,他引:5
Summary A calendar of female sporogenesis and gametogenesis was made for both apomictic tetraploid (2n=4x=36) Brachiaria brizantha and Brachiaria decumbens and their apomictic F1 hybrids with sexual tetraploid (2n=4x=36) Brachiaria ruziziensis. Microgametogenesis was used as a reference. Apospory was facultative in both species and hybrids. Environmental conditions had variable effects on the level of apomixis according to each genotype. Ratios of segregation into sexuals and apomicts in the interspecific hybrids suggest an oligogenic determinism with dominant apomixis in the genus Brachiaria. Highly apomictic and partially male fertile hybrids were identified and will be used in an improvement program to transfer genes for apomixis into the sexual species B. ruziziensis. 相似文献
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Tiago Miqueloto Cauby de Medeiros Neto Clovis David Medeiros Martins Rodrigo Amorim Barbosa Sila Carneiro Da Silva André Fischer Sbrissia 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(3):208-214
ABSTRACTThe aim of this study was to evaluate the defoliation patterns of individual tillers, efficiency of herbage utilisation, and forage production in continuously stocked Brachiaria humidicola cv. Comum swards during periods of the year of restricted pasture growth. The experiment was conducted at the Embrapa, Campo Grande-MS, Brazil, from April to October 2012. Treatments consisted of two grazing management strategies, defined by two ranges of sward height (10–15 and 20–25 cm) managed under continuous and variable stocking rates. The experiment was conducted as a completely randomised block design with three replications. During periods of resource constraints, grazing management strategies based on ‘steady state’ sward heights did not alter defoliation patterns, herbage utilisation efficiency (HUE), and forage production in Brachiaria humidicola swards under a continuous stocking method. A direct implication of our results is that grazing management strategies during the driest and coldest periods of the year in the tropics should be developed based on the conditions most suitable for better promoting faster pasture recovery and a return to production in the following spring; it is unlikely that any grazing management strategy would be successful in increasing herbage production and/or HUE in periods of restricted pasture growth. 相似文献
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海南省西南半干旱地区臂形草引种试验 总被引:3,自引:0,他引:3
在海南省东方县半干旱条件下,对5种臂形草属牧草(Brachiaria spp.)进行3 a区域性品比试验,结果表明,产量最高的是杂交臂形草(B.hybrid CIAT9201/1873)和网脉臂形草(B.dictyoneura CIAT6133),年干草产量分别达到18 938和16 869 kg/hm^2,分别比对照热研6号珊状臂形草(B.brizantha cv.Reyan No.6,年干草产量12 694 kg/hm^2)增产49.2%和32.9%。其中杂交臂形草是株丛型草,可用作刈割型饲料;网脉臂形草由于草质硬,生长速度快、草层密度大、耐践踏,耐酸性瘦土,特别适合用作人工草地和覆盖用草;刚果臂形草茎叶柔软而毛少,适口性较好,是饲养幼畜幼禽的优良品种。 相似文献
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Changes in land-uses, fire regimes, and climate are expected to promote savanna expansion in the Amazon Basin, but most studies that come to this conclusion fail to define “savanna” clearly or imply that natural savannas of native species will spread at the expense of forest. Given their different conservation values, we sought to differentiate between species-diverse natural savannas and other types of fire-maintained grass-dominated vegetation that replaced tropical forests between 1986 and 2005 in 22,500 km2 of eastern lowland Bolivia. Analysis of Landsat TM and CBERS-2 satellite imagery revealed that, in addition to 1200 km2 (7.1%) of deforestation for agriculture and planted pastures, 1420 km2 (8.4%) of forest was replaced by derived savannas. Sampling in 2008 showed that natural savannas differed from forest-replacing derived savannas floristically, in soil fertility, and in fuel loads. Natural savannas typically occurred on sandy, acidic, nutrient-poor soils whereas most derived savannas were on comparatively fertile soils. Fuel loads in derived savannas were twice those of natural savannas. Natural savannas supported a diversity of grass species, whereas derived savannas were usually dominated by Guadua paniculata (native bamboo), Urochloa spp. (exotic forages), Imperata brasiliensis (native invasive), Digitaria insularis (native ruderal), or the native fire-adapted herb Hyptis suaveolens (Lamiaceae). Trees in derived savannas were forest species (e.g., Anadenanthera colubrina) and fire-tolerant palms (Attalea spp.), not thick-barked species characteristic of savanna environments (e.g., Curatella americana). In addressing tropical vegetation transitions it is clearly important to distinguish between native species-diverse ecosystems and novel derived vegetation of similar structure. 相似文献