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To evaluate the in vitro digestibility of forage legume from semi-arid northeast region using caecal inoculum liquor of ostriches with Reverse Tilley and Terry technique, the alfalfa hay (Medicago sativa) was used as reference food for comparison between hays of canephori (Senna multijuga), clitoria (Clitoria ternatea), leucaena (Leucaena leucocephala), kills pasture (Senna obtusifolia) and thrush (Mimosa caesalpiniifolia). There was, by Duncan test (P<0.05), significant difference to in vitro digestibility of the nutritional fractions among the legume hays resulting in general mean value of 49.62% for dry matter (DIVMS), of 23.38% for crude protein (DIVPB), of 17.88% for insoluble protein in neutral detergent fiber (DIVPIDN), of 34.52% for neutral detergent fiber (DIVFDN) and of 42.07% for neutral detergent fiber corrected for ash and protein (DIVFDNcp). The nutritional composition of feedstuffs influenced the fermentative activity of microorganisms from cecum-colon of ostriches in these in vitro incubations, and the better digestibility values were observed for alfalfa hay, followed by kills pasture and leucaena hays, wich were higher than other legumes from semi-arid. [ABSTRACT FROM AUTHOR]

Desde una perspectiva económica, se estudió un grupo de indicadores en tecnologías de ceba vacuna en pastoreo con Leucaena leucocephala (variedad Perú), con suplementación y sin ella. La investigación se desarrolló en el Instituto de Ciencia Animal, en sistemas con lotes de 150 animales de los genotipos ¾ Holstein x ¼ Cebú comercial y Charolais cubano: cinco con pasto natural y CT-115 (Pennisetum purpureum vc.), y dos con pasto estrella (Cynodon nlemfuensis). Se elaboraron fichas de costo por tratamiento y se calculó el costo/animal, costo/kg PV, costo/ha, costo/$, beneficio/costo (B/C) y el punto de equilibrio (kg carne y animales). Como indicadores financieros se estimó el margen bruto, ingreso neto y costos directos por hectarea y la rentabilidad y recuperación de inversión (años). Como patrón se utilizó el dólar estadounidense (USD), para posibilitar el análisis de transferencia tecnológica y el ahorro de importaciones. La utilización del silvopastoreo con leucaena fue positivo, independientemente del manejo de insumos y sistemas aplicados. Sin embargo, los mejores indicadores correspondieron a los sistemas no suplementados con menores costos/kg, por ha, animal y PV producido y mayor B/C, aunque el Charolais mostró indicadores similares, debido a su favorable respuesta económica ante la aplicación de suplementos. Los sistemas más intensivos presentaron los mayores márgenes brutos e ingresos netos por hectárea y mayor nivel de costos directos. La rentabilidad y recuperación de inversiones fueron favorables al empleo de menores insumos. El análisis demuestra la utilidad del uso de estos indicadores para viabilizar la selección de alternativas productivas, optimización de recursos y ahorro potencial de importaciones para Cuba. [ABSTRACT FROM AUTHOR]

Abstract: Leucaena leucocephala is widely used as raw material for the manufacture of paper and packaging material and in biomass based power plants in the state of Andhra Pradesh, Southern India. Experiments were conducted to study the affect of tree density on the growth, biomass partitioning and wood productivity. Six treatments 1 × 1 m, 1.3 × 1.3 m, 3 × 0.75 m, 3 × 1 m, 5 × 0.8 m and 3 × 2 m corresponding to a tree density of 10,000, 6666, 4444, 3333, 2500 and 1666 were evaluated with leucaena variety K636. At 51 months after planting, spacings significantly influenced tree height, diameter at breast height (DBH), number of branches and biomass partitioning. Wider tree rows resulted in greater tree height and diameter growth resulting in higher per plant productivity. At harvest, 70% of trees in 3 × 2 m attained a diameter of more than 7.5 cm, while 35% of the trees attained the same DBH in 1 × 1 m spacing. Increased spacing levels decreased the relative amount of growth allocated to the bole of the tree. Marketable biomass yield was highest with 1 × 1 m spacing. Spacing of 3 × 0.75 m produced marketable biomass comparable to that of 1 × 1 m and greater proportion of stems with more than 5 cm diameter. Leucaena can be grown at 3 × 0.75 m spacing either for pulpwood or fuelwood depending on the prevailing market prices and demand. [ABSTRACT FROM AUTHOR]

Abstract: A selection of the best wood raw materials for cellulose pulp and papermaking from five varieties of the Leucaena has been made (Leucaena diversifolia, Leucaena collinsii and three varieties of Leucaena leucocephala) with growth periods of one, two and three years. In accordance with biomass production and the features of the raw materials and cellulose pulp obtained, L. diversifolia in its second year of growth was selected as the most suitable material for pulp and papermaking. Pulping of L. diversifolia by soda–ethanol was studied using an experimental design in order to investigate the effects of cooking variables: temperature, time, soda concentration, ethanol concentration and wash-disintegrate temperature on the chemical composition of the obtained pulps (yield, kappa number, viscosity, solubles substances, lignin, holocellulose and α-cellulose contents) and the physico-chemical characteristics of paper sheets (tensile index). The results were evaluated using the response surface methodology. The optimum pulping conditions were established for this lignocellulosic material, using the model predictions. The pulp obtained at these conditions has suitable chemical (pulp) and physical (paper sheets) characteristics: yield (46.5%), 1%NaOH solubles (3.04%), hot water solubles (0.63%), ethanol–benzene extractives (0.44%), holocellulose contents (96.7%), α-cellulose contents (75.8%), lignin contents (0.85%), viscosity (1367) kappa number (15.2) and tensile index (19.2kNm/kg). [Copyright &y& Elsevier]

From an economic perspective, a set of indicators was studied for cattle fattening technologies in Leucaena leucocephala (variety Peru) grazing, with supplementation and without it. The research was developed at the Institute of Animal Science, in systems with lots of 150 animals of the genotypes 3/4 Holstein x 1/4 commercial Zebu and Cuban Charolais: five with natural pasture and CT-115 (Pennisetum purpureum cv.), and two with star grass (Cynodon nlemfuencis). Cost records per treatment were elaborated and the cost/animal, the cost/kg LW, the cost/ha, the cost/$, the benefit/cost (B/C), and the point of equilibrium (kg meat and animals) were calculated. As financial indicators, the gross margin, the gross income and the direct costs per hectare and the profitability and the recovery of the investment (years) were estimated. The American dollar (USD) was used as pattern, to make the analysis of technology transference and the safe of importations. The utilization of the silvopastoral system with leucaena was positive, regardless the handling of inputs and applied systems. Nevertheless, the best indicators corresponded to the non-supplemented systems with lower costs/kg, per ha, animal and LW produced and higher B/C, although the Charolais showed similar indicators, due to the favorable economic response to the application of supplements. The most intensive systems presented the highest gross margins and gross incomes per hectare and higher level of direct costs. The profitability and recovery of investments were favorable to the use of lower inputs. The analysis shows the utility of the use of these indicators to make viable the selection of productive alternatives, the optimization of resources and the potential safe of importations to Cuba. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to determine (i) the effects of protein-rich trees (PRTs) and (ii) the effects of leucaena treated with NaOH solution and leucaena plus polyethylene glycol (PEG) on nutrient digestibility, nitrogen (N) balance, urinary purine derivatives excretion and blood metabolites in Thai swamp buffaloes. In Experiment 1, animals were fed with rice straw as a basal diet and one of the four PRT supplements: (i) oven-dried rain tree pods (RTPP, control); (ii) sun-dried leucaena leaves; (iii) sun-dried cassia leaves and (iv) sun-dried mulberry leaves. Fibre digestibility and N balance were lower ( P < 0.05), but microbial N in the rumen was higher ( P < 0.05) in animals supplemented with RTPP than in those fed with the other supplements. In Experiment 2, animals were fed with rice straw as a basal diet and leucaena were treated in one of three ways: (i) untreated (control), (ii) leucaena treated with NaOH solution and (iii) leucaena + PEG. Fibre digestibility and N balance in the rumen improved ( P < 0.05) in animals supplemented with leucaena + PEG, but microbial N was not increased. The study demonstrated a way of using local PRTs for a suitable and worthwhile method to improve the quality of buffalo feeding systems in the tropics. [ABSTRACT FROM AUTHOR]

Twenty three Leucaena spp. accessions of a collection of 180 were evaluated, in order to characterize the performance of their phenological patterns in the establishment stage; the plants were sown at a distance of 6 x 3 m between rows and between plants. The number of pinnae per leaf and of pinnule per pinna was counted; in addition, the length and width of the pinnule were measured, and the quantity of legumes per capitulum, the length and width of the pods were determined. The form of the pinnae, the type and position of the glands and the color of he flowers were taken into consideration. The emergence of flowers and fruits was different among the species of this genus, and it occurred only annually in some of them. The accessions of each species had a similar performance, in the rainy, as well as the dry season, except L. diversifolia CIAT-17503, L. macrophylla CIAT-17233 and L. esculenta CIAT-17229 (which remained in vegetative stage). Likewise, the individual flowers of the Leucaena species and accessions were observed to be generally small. It is concluded that there are differences among the species and accessions evaluated in this stage; as well as in the performance of their flowering and fructification patterns. [ABSTRACT FROM AUTHOR]

Twenty three Leucaena spp. accessions of a collection of 180 were evaluated, in order to characterize the performance of their phenological patterns in the establishment stage; the plants were sown at a distance of 6 x 3 m between rows and between plants. The number of pinnae per leaf and of pinnule per pinna was counted; in addition, the length and width of the pinnule were measured, and the quantity of legumes per capitulum, the length and width of the pods were determined. The form of the pinnae, the type and position of the glands and the color of he flowers were taken into consideration. The emergence of flowers and fruits was different among the species of this genus, and it occurred only annually in some of them. The accessions of each species had a similar performance, in the rainy, as well as the dry season, except L. diversifolia CIAT-17503, L. macrophylla CIAT-17233 and L. esculenta CIAT-17229 (which remained in vegetative stage). Likewise, the individual flowers of the Leucaena species and accessions were observed to be generally small. It is concluded that there are differences among the species and accessions evaluated in this stage; as well as in the performance of their flowering and fructification patterns [ABSTRACT FROM AUTHOR]

Five leucaena trees of similar age were chosen in Jiangjia Ravine of Dongchuan, Yunnan Province, China, near which the soil samples were collected by digging profiles 2m in depth and 1m in width. In each section, soil samples at different depths were taken for direct shear experiments to determine the root amount and mechanical composition. It is found that the cohesion and internal friction angle of the undisturbed soil are related to the root amount, depth, clay content and breccias content. Cohesion correlates negatively with root content, a finding that differs from that of other researchers. In addition, internal friction angle correlates positively with all these factors. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the properties of cellulose pulp and paper from different lignocellulosic materials and the heating value and chemical composition of their autohydrolysis liquor. An integral fractionation method was used to assess their potential for the obtainment of energy, sugars and other chemical products. Raw materials included Eucalyptus globulus, Arundo donax, Leucaena diversifolia, Paulownia fortunei, sunflower stalks and Chamaecytisus proliferus. Results showed that the lignocellulosic materials seem to be effective choices for obtaining biomass fuel and cellulose pulp. In addition, the hemicellulose contents of all raw materials were higher than those for eucalyptus.

A total of 12 crossbred (Boer × Anglo-Nubian) goats were chosen from a commercial farm on the basis of similar body weight (25.0 ± 3.1 kg). The goats were housed in individual pens and allowed 3 weeks to adapt to experimental conditions. The goats were randomly allocated to three treatments in a 3 × 3 Latin square experiment (replicated four times). Within each period, each goat was given rice straw as roughage plus the respective treatment diet. The diets were iso-nitrogenous and iso-energetic containing cassava pulp, molasses, urea and commercial mineral and vitamin mix. The experimental treatments were (i) soybean meal (SBM), (ii) partial substitution of SBM with Leucaena ( Leucaena leucocephala) foliage and (iii) partial substitution of SBM with Madras thorn ( Pithecellobium dulce) foliage. Nutrient intakes, ruminal characteristics (pH, ammonia nitrogen and volatile fatty acids), nitrogen balances, plasma urea nitrogen and microbial N supply were not significantly different among treatments. The results of this study indicate that protein foliages from locally grown shrubs and trees can substitute imported feedstuff concentrates (e.g. SBM) as protein supplement for goat production. [ABSTRACT FROM AUTHOR]

Durante cuatro años, se condujo una investigación en un sistema silvopastoril de leucaena-guinea con ocho años de establecido. El objetivo fue evaluar, a través de chequeos poblacionales, la presencia e infestación de los insectos fitófagos asociados al sistema. Se partió de un muestreo estratificado, con una frecuencia mensual. Se definieron los organismos fitófagos y los biorreguladores y se describió la dinámica poblacional de los principales insectos-plaga. Además, se evaluó el daño de los insectos-plaga en los estratos arbóreo y herbáceo. Los datos se analizaron estadísticamente a través de las tablas de contingencia y análisis de comparación de proporciones (chi cuadrado). En leucaena se albergaron las mayores proporciones de fitófagos con hábitos voladores (91.10 %), capturando solo una minoría (8.90 %) en el pasto guinea. En todas las épocas del año que se evaluaron, la arbórea manifestó mayor proporción de organismos, destacándose como principal fitófago el psílido H. cubana con proporciones superiores (P < 0.001) al 60 % en la época de lluvia y 80 % en la seca. Sus índices poblacionales promedio superaron los diez insectos/m2 en la seca y los cinco insectos/m² en la época de lluvia. Sin embargo, no se presentó daño económico en las plantas evaluadas. La santanilla, Wasmannia auropunctata, fue el biorregulador de mayor proporción (P < 0.001) en las épocas lluviosas de 2004 y 2005, así como en la seca de 2005, 2006 y 2007, con proporciones superiores a 50 %. Las hormigas y las arañas le siguieron en proporción y en menor cuantía, de forma estable durante las dos épocas del año. Se recolectaron además, tijeretas (Doru taeniatum) y cotorritas (Diomus bruneri). Se concluye que el psílido Heteropsylla cubana permanece como el principal fitófago en áreas de leucaena-guinea, con incidencia mayor en la época seca, asociado en los rebrotes o puntos de crecimiento de la leguminosa arbórea. Sin embargo, los daños ocasionados por este insecto no produjeron perjuicios económicos, debido a la existencia de especies biorreguladoras que persisten en estos agroecosistemas y ejercen control natural sobre ellas. [ABSTRACT FROM AUTHOR]

Abstract: The objectives of the current study were, firstly to determine the molecular weight of condensed tannins (CTs) of 62-2-8 Leucaena-hybrid Bahru (LLB) and relating it to its protein binding ability, using the local Leucaena leucocephala (LLL) as control and; secondly to evaluate the effect of different levels of CTs of the hybrid LLB on rumen fermentation parameters, including dry matter and nitrogen digestibility and methane gas production. The weight-average molecular weights (M w) of purified CTs extracted from hybrid LLB and local LLL, determined using gel permeation chromatography were near similar, being 2737 and 2872Da, respectively. However, the CTs of the hybrid LLB exhibited stronger protein binding ability than the local LLL (0.305 and 0.420mg, respectively, for LLB and LLL to bind half maximum bovine serum albumin). The above results seems to suggest that molecular mass of CTs, at least for Leucaena forages, is not the sole factor in determining their capability to bind protein. Inclusion of about 20–40mg of CT/g DM of the CTs from hybrid LLB effectively decreased (P<0.05) methane production and in vitro nitrogen digestibility. The above results suggested a potential of using CTs from the hybrid LLB to protect dietary protein from rumen degradation for better utilization in the small intestine of ruminant animals, and in addition to mitigate their enteric methane emission, often implicated as a source of greenhouse gases. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the effect of supplementation with corn distillery residues on the performance of heifers in an association of grass and leucaena. The study was conducted in an area of the Experimental Station "Indio Hatuey" , Perico municipality, Matanzas province, Cuba. The prevailing pasture species was Panicum maximum cv. Likoni and as legume, Leucaena leucocephala. Eighteen heifers, distributed in a completely randomized design in three groups of six animals, were used; the control group did not receive supplementation (A), and the other two groups were supplemented with corn distillery residues in 10% (B) and 20% (C) of the protein requirements with regards to live weight. The chemical composition, dry matter availability, live weight gain, parasite infestation and hematocrit were determined. When analyzing the daily gain per treatments, significant differences (P<0,05) were found and the highest values were obtained in treatment C (805 g/animal/day); while A and B showed 479 and 572 g/animal/day, respectively. The hematocrit values (between 28,1 and 30,5%), as well as the egg count, were maintained, without significant differences among treatments. The supplementation with distillery corn residues was concluded to influence positively the mean daily gain, and it also maintained the hematocrit values within the recommended range for cattle. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate the effect of supplementation with corn distillery residues on the performance of heifers in an association of grass and leucaena. The study was conducted in an area of the Experimental Station "Indio Hatuey" , Perico municipality, Matanzas province, Cuba. The prevailing pasture species was Panicum maximum cv. Likoni and as legume, Leucaena leucocephala. Eighteen heifers, distributed in a completely randomized design in three groups of six animals, were used; the control group did not receive supplementation (A), and the other two groups were supplemented with corn distillery residues in 10% (B) and 20% (C) of the protein requirements with regards to live weight. The chemical composition, dry matter availability, live weight gain, parasite infestation and hematocrit were determined. When analyzing the daily gain per treatments, significant differences (P<0,05) were found and the highest values were obtained in treatment C (805 g/animal/day); while A and B showed 479 and 572 g/animal/day, respectively. The hematocrit values (between 28,1 and 30,5%), as well as the egg count, were maintained, without significant differences among treatments. The supplementation with distillery corn residues was concluded to influence positively the mean daily gain, and it also maintained the hematocrit values within the recommended range for cattle. [ABSTRACT FROM AUTHOR]

Twenty-three Leucaena spp. accessions from a collection of 180 were evaluated, with the objective of learning their performance under establishment conditions and select the most outstanding ones, based on some morphological and yield indicators. The plants were sown at a distance of 6 x 3 m between rows and plants. The evaluated indicators were: plant height, number of branches, stem diameter and yield. L. leucocephala CIAT-17480, CIAT-9438, CIAT-7988, CIAT-7384 and CIAT- 751, as well as L. esculenta CIAT-17225 and CIAT-17229 were the first ones to reach the height and stem diameter according to the established selection criteria. It could be observed that the establishment dynamics of the species from this genus showed differences among the accessions; likewise, it was noticed that all of them fulfilled the selection criteria, although not at the same time. It is concluded that there are intraspecific and interspecific differences in the evaluated material. The most outstanding accessions were L. leucocephala cv. Cunningham, cv. Peru, CIAT-9119, CIAT-9438, CIAT-751, CIAT-7988, CIAT-7384, CIAT-7929, CIAT-17480, cv. Ipil-pil, cv. CNIA- 250, L. lanceolata CIAT-17255, CIAT-17501 and L. diversifolia CIAT-17270, for which their utilization in further studies is recommended. [ABSTRACT FROM AUTHOR]

Twenty-three Leucaena spp. accessions from a collection of 180 were evaluated, with the objective of learning their performance under establishment conditions and select the most outstanding ones, based on some morphological and yield indicators. The plants were sown at a distance of 6 x 3 m between rows and plants. The evaluated indicators were: plant height, number of branches, stem diameter and yield. L. leucocephala CIAT-17480, CIAT-9438, CIAT-7988, CIAT-7384 and CIAT-751, as well as L. esculenta CIAT-17225 and CIAT-17229 were the first ones to reach the height and stem diameter according to the established selection criteria. It could be observed that the establishment dynamics of the species from this genus showed differences among the accessions; likewise, it was noticed that all of them fulfilled the selection criteria, although not at the same time. It is concluded that there are intraspecific and interspecific differences in the evaluated material. The most outstanding accessions were L. leucocephala cv. Cunningham, cv. Peru, CIAT-9119, CIAT-9438, CIAT-751, CIAT-7988, CIAT-7384, CIAT-7929, CIAT-17480, cv. Ipil-pil, cv. CNIA-250, L. lanceolata CIAT-17255, CIAT-17501 and L. diversifolia CIAT-17270, for which their utilization in further studies is recommended. [ABSTRACT FROM AUTHOR]

Leucaena leucaena ssp. leucocephala has become the fourth-most-rampant tree weed in Singapore, after Acacia auriculiformis, Falcataria mollucana, and Spathodea campanulata. The spread of the species around the island in recent times is believed to have been established from seed-contaminated soil, brought in from Malaysia or Indonesia for land reclamation and soil works. However, the species is more easily controlled because of its smaller size. It may be a potential candidate for use in reforestation projects in Singapore's nature reserves, to improve impoverished soils on exposed sites as well as to provide shade for seedling or saplings of forest species planted. More research should be done to ascertain the full potential of this species before categorizing it as another nuisance weed species. [ABSTRACT FROM AUTHOR]

The reliability of a field test kit for the detection and the persistence of Synergistes jonesii bacteria in sheep was investigated in two trials for 12 months. The test kit consisted of a culture medium (Fe2), serum test tubes, disposable syringes and needles, stomach tube, cheesecloth and ferric chloride reagent. The objectives were to test a field kit for practicality and reliability, to assess the spread of the bacteria among sheep flocks within the farm in Phase 1, and to monitor the persistence of the bacteria with and without Leucaena forage in the diet for 5 months in Phase 2. Three sheep flocks (20 young ewes, 30 older ewes and 11 wethers) were screened in Phase 1; and in Phase 2, four wethers were monitored for 19 weeks with and without Leucaena forage in the diet. In Phase 1, wethers tested positive within 6.364 ± 0.48 d, while the ewes took longer (16.5 ± 0.14 d). All flocks were infested with the bacteria even without prior inoculation. In Phase 2, the four wethers on Leucaena diet tested positive within 5.0 ± 0.0 d, but without Leucaena in the diet it took 12.08 ± 0.0, 11.0 ± 4.46, 11.67 ± 5.76, and 6.92 ± 0.0 d, respectively. The bacteria persisted for 5 months without Leucaena in the diet. This confirmed that the field test kit was simple, reliable and fast, and the bacteria are contagious and very persistent. [ABSTRACT FROM AUTHOR]

Mulching with vegetative materials is a highly beneficial and widely-investigated agro-technique in rainfed areas but the adoption of this practice has been constrained due to non-availability of mulch biomass locally. Live mulching with fast-growing annual green manure legumes like sunnhemp ( Crotalaria juncea) or prunings of Leucaena leucocephala grown as hedge rows can be done for moisture conservation as well as nutrient cycling in the maize–wheat cropping system, which is predominantly followed in the high rainfall sub-mountainous region of north-western India. A field experiment was conducted at Selakui, Dehradun during 2000–2004 to study the effect of legume mulching, viz. in situ grown sunnhemp and Leucaena prunings, along with varying N levels, viz. 0, 30, 60 and 90 kg N ha−1 (to maize), and 0, 40 and 80 kg N ha−1 (to wheat) on productivity, soil moisture conservation and soil physico-chemical properties. Intercropped sunnhemp added 0.75–1.45 t dry matter and 21.6–41.3 kg N ha−1 at 30–35 days, while Leucaena twigs added 1.89–4.15 t dry matter and 75.2–161.3 kg N ha−1 at 60–65 days of maize growth. Live mulching with sunnhemp or Leucaena biomass improved soil moisture content at maize harvest (+1.15–1.57%) and crop productivity by 6.8–8.8% over no mulching. Combined use of both the mulching materials was more effective in improving the soil moisture content (+2.08–2.29%) and grain yield (15.1%) over their single application. Response of maize to N fertilizer application was significant up to 90 kg N ha−1, and it was relatively more pronounced under the mulching treatments. Residual effect of mulching on wheat showed an increase in yield of 10.2% with sunnhemp or Leucaena, and 27.9% with sunnhemp + Leucaena. There was an improvement in organic C and total N status of soil, and a decrease in bulk density associated with an increase in infiltration rate due to mulching at the end of 4 cropping cycles. It was concluded that legume mulching is a highly beneficial practice for enhanced moisture and nutrient conservation, leading to increased productivity and soil health of maize–wheat cropping system under Doon valley conditions of north-western India. [ABSTRACT FROM AUTHOR]

Abstract: Samples obtained from two planting experiments with tropical shrub legumes rich in condensed tannins (CT) (Calliandra calothyrsus, Flemingia macrophylla, Leucaena leucocephala) were analysed in detail for CT concentration, composition and properties, as well as for in vitro degradability. The factors evaluated included cultivation site (fertile mollisol with pH 7.8 and bimodal rainfall vs. infertile oxisol with pH 5.0, high Al saturation and unimodal rainfall) and different levels of mineral fertilisation. In vitro ruminal degradability, CT concentration and properties were affected by cultivation site or fertiliser application or both. In Calliandra and Flemingia, the CT concentration showed a trend (P <0.1) to be higher at the site with the infertile soil. This was consistent with the increased (P <0.001) astringency of CT extracts found in Calliandra when plants were cultivated at this site. In Flemingia, however, astringency was reduced (P <0.001) on the infertile soil. There were certain effects of the cultivation site on the anthocyanidin profile of CT from Calliandra and Flemingia, but these were relatively small and could not explain the differences in astringency observed between sites. Fertilisation did not affect (P >0.05) total CT concentration in Calliandra and Flemingia but clearly increased (P <0.01) astringency of the CT extracts. This suggests that not only CT concentration but also properties of CT may be affected by cultivation site and fertilisation. Leucaena did not grow on the infertile soil and site effects could therefore not be evaluated in this species. Fertilisation did not affect (P >0.05) CT concentration and astringency of CT extracts of Leucaena but reduced (P <0.05) the cyanidin proportion in CT. Cultivation site affected several variables describing fermentation dynamics. Foliage of the legumes grown on the infertile soil exhibited lower (P <0.05) gas production rates. Dry matter degradation was lower (P <0.001) and the proportion of dietary N remaining undegraded after in vitro incubation was higher (P <0.001) when Calliandra was grown on the infertile compared to the fertile soil. The present results indicate that the cultivation site may affect the feeding value of CT-containing legumes. Fertilisation could not compensate the negative effects of the cultivation site on CT properties and ruminal nutrient degradation. Selecting appropriate cultivation sites (with higher soil fertility) may contribute to improve the feeding value of certain tanniniferous tropical shrub legumes. [Copyright &y& Elsevier]

With the objective of characterizing the best-performance accessions under nursery conditions, a Leucaena spp. collection, represented by 23 accessions of five species, was evaluated. For that purpose the following elements were measured: seedling height, stem diameter and branch number, dry biomass of the aerial part, root length and dry matter, which served as indicators of the optimum transplantation moment; the seedlings were planted in 26 x 14 cm black polyethylene bags. These features were observed to have remarkable influence on plant development and when a main component analysis was applied, they showed high variability (63,10%) in the first component. Relation was found among plant height, number of leaf growths, dry biomass of the aerial part, dry root mass and root length, and for these features the following accessions stood out: L. leucocephala cv. Cunningham, cv. Peru, CIAT-9119, CIAT-9438, CIAT- 751, CIAT-7988, CIAT-7384, CIAT-7929, CIAT-17480, cv. Ipil-pil, cv. CNIA-250; L. lanceolata CIAT-17255, CIAT- 17501 and L. diversifolia CIAT-17270. It is concluded that there was variability in the collection among the species and among the accessions of each species, and that it is necessary to take into consideration the studied characteristics to define the optimum transplantation moment. [ABSTRACT FROM AUTHOR]

Abstract: The use of the tree-legume Leucaena leucocephala (leucaena), which contains high levels of proteins in its foliage, is limited due to the presence of the toxic free amino acid mimosine. The goal of this research was to develop transgenic leucaena with reduced mimosine content. Two genes, pydA and pydB, encoding a meta-cleavage dioxygenase (EC 1.13.11.2) and a pyruvate hydrolase (EC 3.7.1.6), respectively, from the mimosine-degrading leucaena symbiont Rhizobium sp. strain TAL1145, were used to transform leucaena. These bacterial genes were sequence-optimized for expression in leucaena and cloned into the plant binary vector pCAMBIA3201 for Agrobacterium tumefaciens-mediated transformation. Using immature zygotic embryos as the start explant material, six pydA and three pydB transgenic lines were developed. The presence and expression of the bacterial genes in the transgenic lines were verified by PCR, reverse transcriptase PCR, and Southern analyses. HPLC analyses of the transgenic plants determined that the mimosine contents of the pydA-expressing lines were reduced up to 22.5% in comparison to the wild-type. No significant reduction in mimosine content was observed in the pydB-expressing lines. This is the first example of using a gene from a bacterial symbiont to reduce the toxicity of a tree-legume. [Copyright &y& Elsevier]

Aims: To assess the phenotypic, symbiotic and genotypic diversity scope of Mesorhizobium spp. strains associated with Acacia seyal (Del.) isolated from different agro-ecological zones in Senegal, and uses of susceptible microbial inoculum in a reafforestation process. Methods and Results: A polyphasic approach including phenotypic and genotypic techniques was used to study the diversity and their relationships with other biovars and species of rhizobia. The geographical origins of the strains have limited effect on their phylogenetic and phenotypic classification. Nodulation tests indicated promiscuity of the strains studied, because they were capable of nodulating six woody legume species ( Acacia auriculiformis, Acacia senegal, A. seyal, Acacia tortilis ssp. raddiana, Leucaena leucocephala and Prosopis juliflora). Sequencing and phylogenetic analyses of nodA, nodC and nifH genes pointed out that in contrast to nodA gene, the phylogenies of nodC and nifH genes were not consistent with that of 16S rRNA, indicating that these genes of the A. seyal-nodulating rhizobia might have different origins. Microbial inoculation on nonsterile soil had significant effect on the nodules number and the growth of the seedlings, indicating that these strains of rhizobia might be used as inoculum. Conclusions: The results indicated that A. seyal is a nonselective host that can establish effective symbiosis with Mesorhizobium spp. strains from diverse genomic backgrounds and that the selected A. seyal-nodulating rhizobia could enhance plant growth. Significance and Impact of the Study: These results showed the important role that A. seyal could play in the improvement of reafforestation process as a promiscuous host, which can establish effective symbiosis with rhizobia from diverse genomic backgrounds. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to determine the effect of four rates of nitrogen (N) in the form of leucaena leaves and the time of application on the performance of sorghum plants using the 15N isotopic dilution technique. Results showed that leucaena green manure (LGM) increased dry matter and N yield of sorghum. Nitrogen recoveries of LGM ranged between 23 and 47%. An additional beneficial effect of LGM was attributed to the enhancement of soil N uptake. The best timing of LGM incorporation for obtaining more N derived from LGM, less soil N uptake, and greater dry matter and N in sorghum leaves seemed to be at planting. However, the appropriate timing and rate of LGM to obtain greater dry matter and N yield in panicles, as well as in the whole plant of sorghum, appeared to be at 30 days before planting, particularly a rate of 120 kg N ha-1. [ABSTRACT FROM AUTHOR]

This work was conducted on a of Leucaena spp. collection that was established on acid soil in the Villa Clara province, with the objective of studying the seed production performance of this shrubby species on this soil type. Four treatments were evaluated (A, B, C and D), which were defined through the four quarters of the year, distributed according to a completely randomized design; in addition, the phenology was observed. A highly significant variation (P<0,01) in the total seed and pure seed yield, and the best result was obtained in treatment D. Besides, in this treatment the lowest weight of 1 000 seeds was observed, which represented a higher number of seeds per kilogram and a lower cost per kilogram of seed ($4,80). Variation was observed regarding the phenology patterns of flowering and fructification of the different studied species and accessions. The harvest of seeds from Leucaena is concluded to be more economical when it is carried out in the last quarter of the year under the conditions this trial was conducted. [ABSTRACT FROM AUTHOR]

Litterfall and fine root production is a major pathway for carbon and nutrient cycling in forest ecosystems. We investigated leaf litterfall, fine-root mass, production and turnover rate in the upper soil (0–30 cm) under four major tree species ( Leucaena leucocephala, Acacia nilotica, Azadirachta indica, Prosopis juliflora) of the semi-arid region of India. All the four tree species showed an unimodal peak of leaf litterfall with distinct seasonality. Leucaena leucocephala and Acacia nilotica had maximum leaf litterfall between September and December while Azadirachta indica and Prosopis juliflora shed most of their leaves between February and May. Annual leaf litterfall of the four species ranged from 3.3 Mg ha−1 ( Leucaena leucocephala) to 8.1 Mg ha−1 ( Prosopis juliflora). Marked seasonal variations in amount of fine root biomass were observed in all the four tree species. Fine root production was maximum in Prosopis juliflora (171 g m−2 y−1) followed by Azadirachta indica (169 g m−2 y−1), Acacia nilotica (106 g m−2 y−1) and Leucaena leucocephala (79 g m−2 y−1). Fine root biomass showed a seasonal peak after the rainy season but fell to its lowest value during the winter and dry summer season. Fine root turnover rate ranged from 0.56 to 0.97 y−1 and followed the order Azadirachta indica > Leucaena leucocephala > Prosopis juliflora > Acacia nilotica. The results of this study demonstrated that Prosopis juliflora and Azadirachta indica had greater capability for maintaining site productivity as evidenced from greater leaf litterfall and fine root production. [ABSTRACT FROM AUTHOR]

This research aimed to evaluate co-inoculation of Bradyrhizobium and Bacillus subtilis on nodulation, N2 fixation and growth of cowpea (Vigna unguiculata) and leucaena (Leucaena leucocephala) grown in a red Oxisol. Treatments consisted by: a) control; b) NPK; c) inoculation with Bradyrhizobium + PK; d) co-inoculation Bradyrhizobium + Bacillus subtilis + PK. There was an increase in nodulation of cowpea with co-inoculation. The shoot dry weight, N accumulation and chlorophyll were higher in both coinoculated and fertilized (NPK) treatments. For leucaena, there were not differences between NPK, inoculated and co-inoculated treatments. The dry weight roots of cowpea and leucaena increased with co-inoculation. The co-inoculation Bradyrhizobium and Bacillus subtilis favored the increase in nodulation of cowpea and it has potential to increase biological N2 fixation and plant growth. [ABSTRACT FROM AUTHOR]

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A study was conducted for two years in an area of 2 058 m² , on a Ferralitic Red soil of the EEPF "Indio Hatuey", which objective was to evaluate the performance of the plant community with the inclusion of leucaena trees. Simple 2 x 1 m plots were used. The studied indicators were: dry matter availability, chemical composition, floristic composition of the pastureland, population, height and diameter of leucaena. In the floristic composition of the pastureland, the predominance of P. maximum (P<0,001) could be observed. This association allowed a 6% increase in the population of the improved pasture; while leucaena increased its diameter and height. In turn, total DM availability was higher than 8 t/ha/rotation during the evaluation period. On the other hand, the grasses showed protein levels that oscillated between 9,7 and 11,7%, for the dry and rainy season, respectively; while in leucaena it was higher than 20%. No significant differences were detected in the chemical composition between seasons for any of the species. The floristic composition could be kept over 80% increasing the area covered by the improved pasture; the tree evolved positively in time, increasing the stem diameter. [ABSTRACT FROM AUTHOR]

This study was conducted with the objective of evaluating the agronomic performance of two Leucaena species, associated to Brachiaria brizantha and Clitoria ternatea in a silvopastoral system in the northern coastal prairie of the Nayarit state, Mexico. A randomized block design was used with four repetitions per treatment (legume:grass proportion): 1) L. leucocephala-B. brizantha (30:70); 2) L. glauca-B. brizantha (30:70); 3) L. leucocephala-B. brizantha- C. ternatea (28:52:20); 4) L. glauca-B. brizantha-C. ternatea (28:52:20); 5) B. brizantha (100). Tree growth was measured on a monthly basis, in addition to survival and the performance of the legume:grass relationship in the system. L. glauca showed more height (66 cm) and diameter (0,98 cm) when combined with B. brizantha and C. ternatea, and L. leucocephala showed a higher number of branches (8,7) and more height (4,5 cm). Regarding survival, values of 70 to 80% were observed after a year of implementing the system. According to the results, the mixture of the tree legumes with C. ternatea and B. brizantha is concluded to be an important choice under the ecological conditions of the Mexican dry tropic. [ABSTRACT FROM AUTHOR]

This study was conducted with the objective of evaluating the agronomic performance of two Leucaena species, associated to Brachiaria brizantha and Clitoria ternatea in a silvopastoral system in the northern coastal prairie of the Nayarit state, Mexico. A randomized block design was used with four repetitions per treatment (legume:grass proportion): 1) L. leucocephala-B. brizantha (30:70); 2) L. glauca-B. brizantha (30:70); 3) L. leucocephala-B. brizantha- C. ternatea (28:52:20); 4) L. glauca-B. brizantha-C. ternatea (28:52:20); 5) B. brizantha (100). Tree growth was measured on a monthly basis, in addition to survival and the performance of the legume:grass relationship in the system. L. glauca showed more height (66 cm) and diameter (0,98 cm) when combined with B. brizantha and C. ternatea, and L. leucocephala showed a higher number of branches (8,7) and more height (4,5 cm). Regarding survival, values of 70 to 80% were observed after a year of implementing the system. According to the results, the mixture of the tree legumes with C. ternatea and B. brizantha is concluded to be an important choice under the ecological conditions of the Mexican dry tropic. [ABSTRACT FROM AUTHOR]

A trial was conducted with seeds of Leucaena spp accessions harvested on acid soil and stored under ambient conditions, in order to determine the period and intensity of dormancy and its breaking. For that purpose a simple classification design and four replications were used, with the following treatments: 1) untreated seed (control); 2) coat cut; and 3) water at 80°C for 2 minutes. In each one of the accessions there were significant differences among the applied treatments and the highest germination values were found with the seed coat cut. All the accessions showed dormant state (between 10 and 98%), which was observed in the germination of the control and the viability with the seed coat cut. The highest dormancy values in the seeds harvested in 2006 were detected in L. macrophylla CIAT 17233, L. macrophylla CIAT 17231, L. diversifolia CIAT 17270 and L. leucocephala IH-1140, which hardness was 98,0; 97,0; 80,0 and 74,7%, respectively; in the seeds harvested in 2003 and 2004, the hardness percentages were 89,0; 69,0 and 60,0% for L. lanceolata CIAT 17252, L. macrophylla CIAT 17238 and L. leucocephala cv. K-67, respectively. The seeds of the accessions were concluded to show postharvest dormancy, which varied between 10 and 98%. In addition, thermal scarification caused dormancy breaking, for which the application of this procedure before planting to Leucaena spp seeds harvested on acid soil in Cascajal, is recommended. [ABSTRACT FROM AUTHOR]

A study was conducted for two years in an area of 2 058 m² , on a Ferralitic Red soil of the EEPF "Indio Hatuey", which objective was to evaluate the performance of the plant community with the inclusion of leucaena trees. Simple 2 x 1 m plots were used. The studied indicators were: dry matter availability, chemical composition, floristic composition of the pastureland, population, height and diameter of leucaena. In the floristic composition of the pastureland, the predominance of P. maximum (P<0,001) could be observed. This association allowed a 6% increase in the population of the improved pasture; while leucaena increased its diameter and height. In turn, total DM availability was higher than 8 t/ha/rotation during the evaluation period. On the other hand, the grasses showed protein levels that oscillated between 9,7 and 11,7%, for the dry and rainy season, respectively; while in leucaena it was higher than 20%. No significant differences were detected in the chemical composition between seasons for any of the species. The floristic composition could be kept over 80% increasing the area covered by the improved pasture; the tree evolved positively in time, increasing the stem diameter. [ABSTRACT FROM AUTHOR]

Chemical components of wood strongly influence the characteristics, properties and opportunities for use of natural composites. The main objective of the study was to determine basic chemical components of Leucaena leucocephala from 8- and 16-year-old trees and to correlate the effects of chemical components with properties of its oriented strand board. Besides age, the effects of tree portions, namely, top, middle and bottom were also studied. Leucaena leucocephala wood was analysed for holocellulose, lignin, ash and ethanol-toluene, cold water, hot water and 1% natrium hydroxide solubles. Oriented strand boards which were produced from the samples were evaluated for their mechanical and physical properties based on two resin levels (7 and 9%), two target board densities (700 and 800 kg m-3) and two strand sizes, namely, S1 (12.7-19.0 mm) and S2 (6.3-12.7 mm). This study revealed that tree portion significantly affected cold and hot water solubles, the solubilities of alkali and alcohol toluene, and also the ash and holocellulose contents of L. leucocephala. Only the solubility of alcohol toluene and lignin and holocellulose contents were affected by age. Although the correlation of some chemical components was significant, the correlation coefficients were relatively small, thus, indicating the loose association between the factors and board properties. It could be deduced that board properties had less association with chemical components but were more dependent on the resin content, board density and strand size used in the study. Generally, 8-year-old wood was found to be a suitable raw material for the manufacture of oriented strand board. [ABSTRACT FROM AUTHOR]

A study was carried out at Mocochá, Yucatán, México with the objective of determining whether the application of bentazon, imazethapyr or metribuzin would improve postemergence (POST) weed control without damaging a huaxin (leucaena, guaje, leadtree, wild tamarind) {Leucaena leucocephala (Lam.) de Wit} and insurgente grass (Brachiaria brizantha Richard Stapf) association. In both June 2004 and 2005, insurgente grass (INS) and huaxin (HUA) were seeded in an arrangement of two by one rows, respectively. Herbicide treatments were a single application of bentazon, imazethapyr or metribuzin at three different rates each, and the same herbicides at a single rate but applied sequentially two and three times during the growing season. Metribuzin damaged INS (10 to 95 %) and HUA (55 to 100 %) in both years. Overall, both forage species were tolerant to bentazon and imazethapyr. In 2004, both bentazon and metribuzin showed a greater weed control (82 %) than imazethapyr (70 %); in 2005, weed control was similar for all three herbicides (P>0.05), which averaged a moderate 65 %. This study shows that an increase in 1,000 kg DM ha-1 of weed biomass, decreases forage yield for this association by 190 kg DM ha-1. Forage yields with bentazon applied three times at a 0.8 kg a.i. ha-1 rate were similar to those in the weed-free control. In tropical areas, bentazon should be an interesting option for weed control in insurgente-huaxin associations. [ABSTRACT FROM AUTHOR]

The nutritive value of edible forage from Leucaena leucocephala cv. Cunningham (CUNN) and cv. CNIA-250 (CNIA) was determined during the rainy ( R) and dry ( D) seasons of Cuba without fertilization or irrigation. Forage was supplied ad libitum and the French system of total faeces collection was used for nutritive value determination and expression by using six adult castrated Pelibuey wethers for each determination. There were noticeable differences in the chemical composition and nutritive value between the two cultivars which were also influenced by year season. The highest protein and energy content were found in CNIA and during the rainy season which could also explain its higher forage intake and digestibility, while CUNN expressed higher DM and nutrient yield throughout the year, mainly due to advantages in tree size and morphology (higher ramification and proportion of leaves, and acceptable branch length). Quality and nutritive value results indicated that these Leucaena cultivars have a suitable potential as supplements for sustainable ruminant nutrition strategies during both seasons of the year; CNIA, because of its smaller height, is strongly recommended for agrosilvopastoral small ruminant browsing systems. [ABSTRACT FROM AUTHOR]

Twenty-four yearling steers of 134kg of average LW were handled in a completely randomized design to compare the effect of a multiple mixture of herbaceous legumes and Leucaena leucocephala on the microbial population and fermentative products in the rumen of Zebu upgraded yearling steers. The treatments were: (A) Leucaena leucocephala, and (B) multiple mixture of herbaceous legumes, composed of Neonotonia wightii, Pueraria phaseoloides, Macroptilium atropurpureum, and Centrocema pubescens. The stocking rate was of three animals/ha and the experiment lasted 150 d. The use of the multiple mixture of herbaceous legumes tripled the population of cellulolytic bacteria in rumen (11.1 and 34.2 x 106 cfu/mL for A and B, respectively). The populations of total viable and proteolytic bacteria were higher in the rumen of yearling steers fed the multiple mixture of herbaceous legumes, compared with those on L. leucocephala. There were not differences in the populations of fungi and protozoa. The concentration of ammonia was 13.58 and 18.26 mmol/L for L. leucocephala and herbaceous legumes, respectively. The multiple mixture of herbaceous legumes increased in 12 % the concentration of total short-chain VFAs. The concentration of acetic acid was 84.78 and 102.68 mmol/L, and that of propionic, 20.22 and 14.13 % for A and B, respectively. It was concluded that the grazing on herbaceous legumes increases the cellulolytic organisms and enhances the microbial composition in rumen, compared with L. leucocephala, although both systems are appropriate to keep an adequate rumen functioning in pre-fattening yearling steers. [ABSTRACT FROM AUTHOR]

The productive performance of twenty-four 5/8 Holstein x 3/8 Zebu crossbred bulls of 490 d of age was evaluated from 228.28 kg of liveweight (LW) until 412.24 kg of LW at slaughter. The animals grazed in 6 ha of a silvopastoral system at 100 % association of Leucaena leucocephala and grasses. In the dry season, in alternate days, they had access to 2 ha of biomass bank of Pennisetum purpureum cv. Cuba CT-115. Each area was divided into 8 paddocks. The auto-grazing was used without fertilization or irrigation. The occupation and resting times were of 7 and 49 d, respectively. The stocking rate was of 3 and 4 animals/ha in the silvopastoral system plus the biomass bank and in the silvopastoral system in the dry and rainy seasons, respectively. They consumed 1.50 kg/animal/d of rumen activating supplement. The daily average gain (DAG) of LW was of 519.35 and 609.76 g for the dry and rainy season, respectively. The system guaranteed the fulfillment of the protein requirements and permitted supplying 1.24 t/ha of LW at slaughter, with animals of 26.72 months of age. It was corroborated the need for working with smaller stocking rates and/or supplements with higher nutritive value to increase the DAG of LW and slaughter at early ages and get better market results. [ABSTRACT FROM AUTHOR]

The biomass production and the nutritive value of three tropical shrub legumes with condensed tannins (CT) ( Calliandra calothyrsus, Flemingia macrophylla, Leucaena leucocephala) and two without CT ( Cratylia argentea, Desmodium velutinum) as nitrogen-rich feed supplements for ruminants were assessed in two field experiments in Colombia. In one experiment, conducted on two different typical tropical soils (mollisol vs. oxisol; pH, 7·8 vs. 5·0; P content, 43 vs. 2 mg kg DM−1), the effects of low and high levels of fertilizer application with P, K, Ca, Mg and S were tested in both the dry and rainy seasons. In a second experiment on the oxisol, the effect of a lower level of application of either P or S fertilizer was assessed. On the oxisol, C. calothyrsus and F. macrophylla had the highest biomass production (93 and 100 g DM plant−1 in 9 weeks respectively) but the dry season caused extremely low DM yields in all species tested. Leucaena leucocephala did not grow on the oxisol but had the highest biomass production on the mollisol (454 g DM plant−1 in 9 weeks). On the oxisol, the mineral concentrations of the forage were below the requirements of ruminant livestock. Fertilizer treatment had no clear effects on the nutrient composition of the forage. The non-CT shrub C. argentea had the highest concentrations of most minerals in its forage. [ABSTRACT FROM AUTHOR]

Se manejaron 24 añojos de 134 kg de PV promedio en un diseño completamente aleatorizado para comparar el efecto de una mezcla múltiple de leguminosas herbáceas y Leucaena leucocephala en la población microbiana y productos fermentativos del rumen de añojos mestizos de Cebú. Los tratamientos fueron: (A) Leucaena leucocephala y (B) mezcla múltiple de leguminosas herbáceas, integrada por Neonotonia wightii, Puerariaphaseoloides, Macroptilium atropurpureumy Centrocemapubesces. La carga animal fue de tres animales/ha y la duración del experimento, de 150 d. La utilización de la mezcla múltiple de leguminosas herbáceas triplicó la población de bacterias celulolíticas del rumen (11.1 y 34.2x 106 ufc/mL para A y B, respectivamente. Las poblaciones de bacterias viables totales y proteolíticas fueron superiores en el rumen de los añojos que se encontraban en la mezcla múltiple de leguminosas herbáceas con respecto a los que se hallaban en L. leucocephala. No hubo diferencias en las poblaciones de hongos y protozoos. La concentración de amoníaco fue 13.58 y 18.26 mmol/L para L. leucocephala y leguminosas herbáceas, respectivamente. La mezcla múltiple de leguminosas herbáceas incrementó en 12 % la concentración de AGCC totales. La concentración de ácido acético fue 84.78 y 102.68 mmol/L y la de propiónico, 20.22 y 14.13 % para A y B, respectivamente. Se concluye que el pastoreo con leguminosas herbáceas incrementa los organismos celulolíticos y mejora la composición microbiana ruminal en relación con L. leucocephala, aunque ambos sistemas son apropiados para mantener el adecuado funcionamiento del rumen en añojos en pre ceba. [ABSTRACT FROM AUTHOR]

Se evaluó el comportamiento productivo de 24 machos mestizos 5/8 Holstein x 3/8 Cebú, de 490 d de edad, desde los 228.28 kg de peso vivo (PV) hasta los 412.24 kg de PV al sacrificio. Los animales pastaron en 6 ha de un silvopastoreo 100 % asociado de Leucaena leucocephala y gramíneas. En la época poco lluviosa, en días alternos, tuvieron acceso a 2 ha de banco de biomasa de Pennisetum purpureum vc. Cuba CT-115. Cada área se dividió en 8 cuartones. Se empleó el autopastoreo, sin fertilización ni riego. Los tiempos de ocupacióny reposo fueron de 7 y 49 d, respectivamente. La carga fue de 3 y 4 animales/ha en el silvopastoreo más el banco de biomasa y en el silvopastoreo, en las épocas poco lluviosa y lluviosa, respectivamente. Consumieron 1.50 kg/animal/d de suplemento activador del rumen. La ganancia media diaria (GMD) de PV fue de 519.35 y 609.76 g durante las épocas poco lluviosa y lluviosa, respectivamente. El sistema garantizó el cumplimiento de los requerimientos proteicos y permitió suministrar 1.24 t/ha de PV al sacrificio, con animales de 26.72 meses de edad. Se corroboró la necesidad de trabajar con cargas menores y/o suplementos con mayor valor nutritivo que permitan aumentar la GMD de PV, para lograr el sacrificio a edades tempranas y obtener mejores resultados en el mercado. [ABSTRACT FROM AUTHOR]

Pyrolysis of alternative biomasses, which contributes to the recovery of arid soils and does not compete with alimentary biomass, could increase use of biomass as feedstock in energy production facilities. In this sense, in order to optimize this thermal process and gain better insight the origin and evolution of the main produced volatiles, nonisothermal thermogravimetry coupled to mass spectrometry (TG/MS) has been applied for samples of two biomasses [Leucaena Leucocephala(Leucaena) and Chamaecytisus Palmensis(Tagasaste)], which find application as energy crops and contribute to soil restoration. In a first stage, autocatalytic kinetics has been used in order to obtain the mass loss rate profiles (DTG) of each biomass pseudocomponent (hemicellulose, cellulose, lignin, and extractives) during pyrolysis. In a second stage, the experimental mass spectrometry signals of the main volatiles (CO, CO2, and H2O) have been simulated using a linear combination of the previously calculated DTG profiles. The accurate fitting obtained, explains the origin of these volatiles from a simple volatization process, mainly from lignin. In a third stage, in order to simulate the hydrogen signal, it has been necessary to consider the char produced during the volatization process. According to the model, the charring process explains close to 77 wt % of the total hydrogen obtained during pyrolysis. Considering the specific char production of each biomass pseudocomponent, it is possible to measure their individual contributions to hydrogen production: hemicellulose, 27.5; cellulose, 9.7; and lignin, 60.9 wt %, for Leucaena. Taking into account the composition of the samples, the relation between the specific hydrogen productions of the single pseudocomponents (hemicellulose:cellulose:lignin) can be calculated: 3.4:1.0:7.6. [ABSTRACT FROM AUTHOR]

Descriptive analysis (DA), principal components (PCA) and linear correlations (LC) were utilized in order to characterize the nutritional composition of leguminous foliage species of the genus Pithecellobium, Gliricidia, Leucaena, Samanea, Acacia, Bauhinia, Cassia and Pentaclethra; and other non leguminous genus: Chlorophora, Morus, Guazuma, Cordia, Trichantera, Tithonia, Moringa, Azadirachta, Bulnesia, Capparis, Hibiscus and Wedelia. Chemical composition, secondary metabolites and dry matter (DMD) and crude protein (CPD) digestibility were estimated. The species showed excellent chemical composition for its use as a supplement in animal feed (CP: 23.46 ±4.43%; NDF: 39.33 ±2.55%; ashes: 9.78 ±4.35%; DMD: 64.98 ±14.42%; CPD: 69.15 ±15.89%). However, leguminous species exhibited higher concentrations of condensed tannins (4.06 ±4.01 vs 0.49 ±0.31%), precipitant tannins (1.95 ±1.37 vs 0.28 ±0.23%) and protein digestibility using pepsin (72.51 ±14.64 vs 66.90 ±16.92%) than the non-leguminous species. Although the trypsin inhibition percentage was similar between the two groups (50.84 ±6.81 vs 50.92 ±8.94), the activity of these inhibitors (3.29 ±2.76 vs 1.55 ±0.39) and the number of inhibited units (625.10 ±524.01 vs 323.33 ±135.31) was higher in the leguminous forage. According to the DA, PCA and LC results, the leguminous species exhibited marked differences in the phytochemical profile pattern when compared with the rest. The precipitating tannins in the leguminous species affected the digestibility of nutrients fractions, while phenols and sterols contained in the non-leguminous forages exhibited greater antinutritional potential. [ABSTRACT FROM AUTHOR]

An evaluation was done of the effect of leucaena height (90 and 120 cm) on the ingestive behavior (IB) of Zebu cattle (n=10) during three annual seasons (northwind, dry and rainy) in dry tropical vegetation in Yucatan state, Mexico. Bite rate (b min-1), grazing time (sec) per feeding station (GTS) and movement time (sec) between feeding stations (MTS) were documented by direct observation. Bite size (g bite-1) and intake rate (g min-1) were calculated. Leucaena height affected some IB components. The height x season interaction was significant (P<0.05) for bite rate, bite size and intake rate. Bite rate was higher in the 90 cm treatment than in the 120 cm treatment during the rainy (39 vs 37) and dry seasons (38 vs 34). Bite size was larger in the 90 cm treatment (> 0.50 g) than in 120 cm treatment (0.46 g) in the dry and northwind seasons; intake rate followed the same pattern. GTS was only significantly different for the main effect of season; it was highest during the rainy season, following by the northwind and dry seasons. MTS did not differ (P>0.05) between treatments. A leucaena height of 90 cm favored higher total and available DM yield, which resulted in a higher intake rate over the short-term in two of the three studied seasons. [ABSTRACT FROM AUTHOR]

An endophagous seed predator, Acanthoscelides macrophthalmus (Coleoptera: Chrysomelidae: Bruchinae), utilizes Neotropical Leucaena (Fabaceae: Mimosoideae). One of its hosts, Leucaena leucocephala, is a fast-growing nitrogen-fixing tree that serves as a multipurpose beneficial plant but eventually becomes an aggressive invader where it was introduced. Herein, we report A. macrophthalmus invasion of the Far East, South Asian tropics and subtropics (Japanese Pacific Islands, Taiwan, Southern China, Northern Thailand and Southern India). Of other field-collected mimosoid legumes, an introduced tree, Falcataria moluccana, in Taiwan was found to be used by the seed predator. Conversely, our published work review revealed that the seed predator had retained high host specificity to Leucaena species in its native and introduced regions. Acanthoscelides macrophthalmus was able to utilize aphagously postharvest mature seeds for oviposition and larval development, which is a trait of post-dispersal seed predators. We confirmed that A. macrophthalmus that was reared on L. leucocephala was able to utilize F. moluccana as well. Although the relatively high host specificity of the oligophagous beetle is suitable for controlling the weedy L. leucocephala, the potential host range expansion confirmed by this study must be cautioned. [ABSTRACT FROM AUTHOR]

Fur condition in wild ringtailed lemurs, Lemur catta, was recorded during September–November birth seasons 2001–2006 at Berenty Reserve, Madagascar. Body coat condition was scored on a scale from BS 0: full, smooth coat with guard hairs, to BS5: half or more of back and limbs hairless. Tail condition was scored from TS 0: full, to TS 5: half or more hairless. Where troop core areas included stands of Leucaena leucocephala, alopecia was dramatically more frequent than in similar areas without leucaena, including many animals with score BS5 or TS5, “bald lemur syndrome.” Female coats were worse than males,' possibly related to female dominance and access to this preferred food. Tails in non-leucaena-feeding females tend to remain full, even if coats deteriorate, but with leucaena-feeding female tails are highly correlated with coat condition and equally bare. Coat and tail condition in L. catta reflected not only the dietary toxin but individual differences as well as differences between adjacent troops that may result from territorially mediated access to the environment. Leucaena contains the non-protein amino acid mimosine, a known cause of alopecia, wasting, and organ damage in livestock, although the effects are usually reversible. This is the first case of its effect in wildlife. Leucaena is an agroforestry tree introduced throughout the tropics. In high dietary concentrations leucaena might potentially affect any browsing mammal. Am. J. Primatol. 71:199–205, 2009. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]