Journal articles on the topic 'Digitaria decumbens Stent (Pangola)'

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1

Teakle, DS, S. Hicks, RM Harding, RS Greber, and RG Milne. "Pangola stunt virus infecting pangola grass and summer grass in Australia." Australian Journal of Agricultural Research 39, no. 6 (1988): 1075. http://dx.doi.org/10.1071/ar9881075.

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A widespread disease of pangola grass (Digitaria decumbens) and summer grass (D. ciliaris) in south-eastern Queensland was characterized by a bunched and stunted growth habit, yellow or red discolouration of the foliage, seed heads with crimped, distorted racemes, and sometimes premature plant death. Virus-like particles present in extracts of diseased plants were unstable, 50-70 nm in diameter, had a core and outer coat and were morphologically similar to particles of viruses in the genus Fijivirus, family Reoviridae. The particles were shown by immune electron microscopy to be serologically closely related to pangola stunt and maize rough dwarf viruses, but unrelated to oat sterile dwarf virus. Similar virus-like particles were observed in crystalline arrays in ultrathin sections of cells in vein enations of D. ciliaris. Extracts of diseased pangola grass and summer grass contained 10 double-stranded RNA species, which were somewhat similar in size to those reported for pangola stunt virus. A planthopper, Sogatella kolophon, which is related to the South American vector of pangola stunt virus, S. furcifera, was associated with diseased pangola grass and summer grass in the field, and was shown to be a vector. However, efforts to infect maize, a major host of maize rough dwarf virus, were unsuccessful. On the basis of these properties the Australian virus is considered to be pangola stunt virus.
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2

Esqueda-Esquivel, Valentín Alberto, and Oscar Hugo Tosquy-Valle. "Efectividad de métodos de control de malezas en la producción de forraje del pasto pangola (Digitaria decumbens Stent.)." Agronomía Mesoamericana 18, no. 1 (April 3, 2006): 1. http://dx.doi.org/10.15517/am.v18i1.5031.

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3

De Almeida, Abraão Rodrigues, Isabel Correia Da Silva, Israel Joaquim da Silva Filho, Evaldo Barbosa de França Júnior, Kedma Maria Silva Pinto, Pablo Radamés Cabral De França, Márcio Fléquisson Alves Miranda, and José Carlos Da Costa. "Avaliação de bancos de sementes de plantas daninhas em áreas de pastagens cultivadas com Digitaria decumbens stent. cv Pangola sob diferentes manejos / Evaluation of weed seed banks in pasture areas cultivated with Digitaria decumbens stent. cv Pangola under different managements." Brazilian Journal of Development 8, no. 2 (February 23, 2022): 14428–46. http://dx.doi.org/10.34117/bjdv8n2-391.

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4

Norton, BW, and MJ Deery. "The productivity of Angora goats grazing improved and native pastures in south-eastern Queensland." Australian Journal of Experimental Agriculture 25, no. 1 (1985): 35. http://dx.doi.org/10.1071/ea9850035.

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Two groups of Angora wether goats were grazed over 1 year on replicated areas (0.4 ha each) of either pure N-fertilized Pangola grass (Digitaria decumbens Stent.) pasture or native pastures containing Acacia, Eucalyptus and groundsel (Baccharis halimfolia L.) regrowth. Half of the goats in each group were given a cobalt bullet and their health, liveweight change and fleece growth were monitored. When adequate levels of native pasture were available (>800 kg green matter/ha) performance of goats on the different pastures was similar over the spring and summer grazing periods. In the winter period, fleece growth rate and yield were significantly (P<0.05) lower and liveweight loss (11 g/day) occurred in goats grazing native pastures. In the same period, goats on Pangola grass pastures supplemented with cobalt continued to grow (39 g/day) and maintained high fleece yields while unsupplemented goats on the same area lost weight rapidly (84 g/day), indicating the onset of cobalt deficiency. Over a 9-month period, the population of regrowth acacias and eucalypts less than 1.5 m high were markedly reduced, and groundsel was completely eliminated from the area. In this period, the palatable native grasses were selected in preference to blady grass (Imperata cylindrica (L.) Beauv.), which increased as a proportion of declining total grass yield.
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5

Ferreira, Walter Motta, and Genário Sobreira Santiago. "Desempenho produtivo de coelhos criados em diferentes densidades populacionais." Revista Brasileira de Zootecnia 28, no. 1 (February 1999): 113–17. http://dx.doi.org/10.1590/s1516-35981999000100016.

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O objetivo deste experimento foi estudar os efeitos da densidade populacional sobre o desempenho produtivo de coelhos para corte na fase de recria. Foram utilizados 108 coelhos da raça Nova Zelândia Branco, de ambos os sexos, desmamados aos 28 dias e alojados aos 35 dias de idade por um período experimental de 6 semanas, em gaiolas de arame galvanizado, de dimensões 0,6 x 0,6 x 0,375 m, equipadas com comedouro automático e bebedouro tipo "nipple", instaladas em galpões semi-abertos. Os animais foram alimentados à vontade com ração peletizada comercial contendo 16% de proteína bruta (PB), 11,84% de fibra em detergente ácido (FDA), 17,49% de fibra em detergente neutro (FDN), 1,20% de cálcio (Ca), 0,60% de fósforo (P) e 2500 kcal de energia digestível (ED)/kg, ad libitum, em todo período experimental, e suplementados a partir dos 56 dias de idade com feno de capim Pangola (Digitaria decumbens, STENT) contendo 4,04% PB; 37,31% FDA; 52,04%FDN; 0,61% Ca; 0,10% P; e 1180 kcal ED/kg, oferecido na quantidade de 50 gramas por animal/dia. As densidades populacionais testadas foram de 1200, 900, 720 e 600 cm²/animal, equivalentes às lotações de 3, 4, 5 e 6 animais por gaiola, respectivamente. O aumento da densidade populacional acarretou diminuição significativa do ganho de peso diário e do consumo diário de ração por animal alojado, sem influir na conversão alimentar e no rendimento de carcaça. Não houve efeito de sexo nas variáveis estudadas. A mortalidade ocorrida no período experimental não apresentou associação com a densidade populacional.
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6

Ash, AJ, and BW Norton. "Productivity of Australian cashmere goats grazing Pangola grass pastures and supplemented with untreated and formaldehyde treated protein meals." Australian Journal of Experimental Agriculture 27, no. 6 (1987): 779. http://dx.doi.org/10.1071/ea9870779.

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The liveweight change and fleece growth Of Australian cashmere goats were studied in a 14 week grazing experiment (Mar.-June) in south-eastern Queensland. Weaner goats grazed nitro-fertilised Pangola grass (Digitavia decumbens Stent.) pastures and were supplemented every second day with a range of protein meals (60 g crude protein/goat.day), i.itht.1. untreated or fomialdehyde treated. Following high growth rates (> 90 g 1iveweight.day) by all kids early in the experiment, control animals experienced severe weight loss (-40 g/day). Goats given protein supplements performed significantly (P<0.05) better, though they only maintained weight. There were no differences (P> 0.05) in liveweight change between the untreated and formaldehyde treated protein groups. The poor growth of goats in this study was associated with declining feed availability under the high stocking rates used (80 goats/ha) and possibly with a seasonal depression in appetite. Total fleece growth was significantly (P<0.05) increased by protein supplementation, except for sunflower meal. However, cashmere growth (mean � s.e., 16.3 � 2.1 g) was largely unaffected by supplementation, with greater hair growth (64 v. 54 g) being responsible for the improved fleece weight in those goats receiving protein supplements. Kids supplemented with formaldehyde treated protein tended to grow more fleece than did kids given untreated protein meals but the differences were not significant.
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7

ARCHIMEDE, H., M. DULORME, R. TOURNEBIZE, G. SAMINADIN, F. PERIACARPIN, and A. XANDE. "The effects of Gliricidia supplementation on intake and digestion of a Digitaria decumbens hay by Black-belly sheep." Journal of Agricultural Science 137, no. 1 (August 2001): 105–12. http://dx.doi.org/10.1017/s0021859601001198.

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The research was carried out at the animal experimental station of the National Agricultural Research Institute of the French West Indies (Guadeloupe) in 1999. Effects on intake and digestion by sheep of addition of Gliricidia leaves to a diet of 35-day-old Digitaria decumbens (pangola) hay, have been studied. In a first trial (a 4×4 Latin Square design), four rams were fed four diets: hay (G0); hay plus 1300 g of Gliricidia (G0·25), hay plus 2600 g of Gliricidia (G0·50), hay plus 3900 g of Gliricidia (G0·75). Total dry matter intake (DM), hay and Gliricidia intake, total tract and rumen digestibility of DM and its components, microbial and total nitrogen flows were estimated. In a second trial (a 2×2 Latin Square design), the same animals received hay (G0) or Gliricidia (G1·00) ad libitum to estimate the rumen turnover of pangola and Gliricidia fibrous particle. Neutral detergent fibre and crude protein content of the Digitaria decumbens hay and Gliricidia were 746 and 51, 458 and 198 g/kg dry matter respectively. Total dry matter intake (DM) varied from 42·7 to 76 g DM/kg LW0·75 from G0 to G0·75. The rate of substitution of pangola by Gliricidia (decrease of pangola intake for one unit Gliricidia consumed) was 233 g/kg. The digestibility of cell-wall linearly decreased with increasing level of Gliricidia in the diet. No digestive interaction was registered in the mixed diets. The total nitrogen and microbial nitrogen duodenal flows increased with the level of Gliricidia in the diet. The rumen turnover of fibrous particles of Gliricidia was double that of pangola. The incorporation of Gliricidia in diets increases their nutritive value by higher intake and intestinal nitrogen duodenal flows, but no positive digestive interaction was observed between pangola hay and Gliricidia leaves.
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8

Minson, DJ, and JB Hacker. "Selecting for nutritive value in Digitaria milanjiana. 2. Intake and digestibility of divergently selected full-sibs compared with Digitaria decumbens." Australian Journal of Experimental Agriculture 26, no. 5 (1986): 551. http://dx.doi.org/10.1071/ea9860551.

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We compare the voluntary intake and digestibility of 6 genotypes selected from 3 F1 families of Digitaria milanjiana for high or low leaf digestibility, and D. decumbens (pangola grass). Swards were harvested on 6 occasions (4 by 4-week regrowths, 1 by 10-week and 1 by 14-week regrowth) and fed to sheep in metabolism cages. Averaged over families and regrowths, high digestibility selections were significantly superior to low digestibility selections in digestibility, voluntary dry matter intake and intake of metabolisable energy. There was a large range in leafiness of the genotypes. Correlations between leafiness and in vivo digestibility, dry matter (DM) intake and intake of metabolisable energy were positive and statistically significant. Comparison of full-sibs at the same percentage stem (80 and 100%) suggested a higher DM intake, digestibility and intake of metabolisable energy of stem from genotypes selected for high leaf digestibility. Averaged over harvests, none of the selected genotypes was significantly superior to pangola grass in digestibility but all were superior in DM intake and 5 in intake of metabolisable energy. The best selected genotype was 35% better than pangola grass in terms of intake of metabolisable energy. Differences in in vitro digestibility of young leaves from vegetative tillers of full sibs, the characteristic on which the genotypes had been selected, were maintained under sward conditions, although differences were reduced.
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9

Lowe, KF, RJ Moss, RT Cowan, DJ Minson, and JB Hacker. "Selecting for nutritive value in Digitaria milanjiana. 4. Milk production from an elite genotype compared with Digitaria eriantha ssp. pentzii (pangola grass)." Australian Journal of Experimental Agriculture 31, no. 5 (1991): 603. http://dx.doi.org/10.1071/ea9910603.

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An elite genotype of Digitaria milanjiana, which had been selected on the basis of improved leaf digestibility, was compared with pangola grass (Digitaria eriantha ssp. pentzii, formerly Digitaria decumbens) in terms of milk production, at Mutdapilly in south-eastem Queensland. Unsupplemented Holstein-Friesian cows grazed nitrogen-fertilised, irrigated swards of 2 grasses using a switch-back experimental design. Pasture management and stocking rate were adjusted to provide the animals with 15 kg of green leaf (on a dry matter basis) per cow per day, so that any differences in milk yield could be attributed to differences in leaf quality rather than to total dry matter yield. Cows grazing the selected genotype produced 0.9 kg more milk, 0.07 kg more butterfat and 0.05 kg more protein per cow per day (5.8, 13.0 and 10.9%, respectively) than those grazing pangola grass. These increases were associated with a small increase in leaf digestibility, a faster rate of breakdown of leaf (in an artificial masticator) and a higher proportion of leaf in the diet chosen by the cows grazing the selected genotype. The results of this experiment demonstrate that a tropical grass selected on the basis of digestibility increased milk production of grazing cows. However, factors other than higher digestibility (such as leafiness) contributed to the improvement in production over that from pangola grass.
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10

Hunter, RA, and BD Siebert. "Digestion of mature pangola grass (Digitaria decumbens) by Bos taurus and Bos indicus cattle." Australian Journal of Agricultural Research 37, no. 6 (1986): 665. http://dx.doi.org/10.1071/ar9860665.

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The digestion of mature pangola grass (Digitaria decurnbens) by Hereford (Bos taurus) and Brahman (Bos indicus) steers was studied. There was no significant difference between breeds in the digestion of organic matter (OM) and cell wall constituents (CWC). The OM digestibility in the whole tract was 0.59 with 90% of the digestion occurring in the stomachs. There was a significantly (P < 0.05) greater nonammonia nitrogen flow through the abomasum in Herefords (66 g/day) than Brahmans (59 g/day). Likewise the ratio of crude protein digested in the intestines to digestible OM (DCPi:DOMI) was higher (P < 0.05) in Herefords (0.120) than in Brahmans (0.102). In both breeds 66% of the nitrogen associated with the CWC was digested in the whole tract, essentially all digestion occurring in the stomachs. These results for pangola grass, especially the DCPi:DOMI ratios, are compared with the digestion characteristics of other tropical grasses and are discussed in terms of the capacity of tropical grasses to meet the protein requirements of growing cattle.
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11

Fujita, H., and L. R. Humphreys. "Variation in seasonal stocking rate and the dynamics of Lotononis bainesii in Digitaria decumbens pastures." Journal of Agricultural Science 118, no. 1 (February 1992): 47–53. http://dx.doi.org/10.1017/s002185960006799x.

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SUMMARYPastures of Digitaria decumbens (pangola grass) previously oversown with Lotononis bainesii at Mount Cotton, south-east Queensland, Australia, were grazed by sheep for 3 years (1985–87), using a factorial combination of seasonal variations in stocking rate.Lotononis behaved as a short-lived plant with a mean half-life of 4·2 months (range 1·6–10·3); rate of mortality was positively related to initial seedling density. The proportion of lotononis remained very low for the first 2 years of the experiment, when conditions were unsuitable for large-scale seedling regeneration, which was also limited by the hardness of the seed reserves. Subsequently, lotononis regenerated well in treatments which combined the following features: (i) light grazing (5 sheep/ha) during the main flowering period of spring-early summer, (ii) heavy short-duration grazing in mid-summer to create a ‘gap’ and (iii) medium or heavy (18 or 27 sheep/ha) grazing during late summer-autumn to reduce competition from pangola grass.The ecological niche of lotononis and the possible use of complementary pastures are discussed.
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12

Alexandre, G. "Elevage à l'herbe des chevreaux Créole après le sevrage." Revue d’élevage et de médecine vétérinaire des pays tropicaux 44, special (May 1, 1991): 99–104. http://dx.doi.org/10.19182/remvt.9228.

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Plusieurs essais concernant l'amélioration de l'élevage à l'herbe des chevreaux Créole après leur sevrage sont menés avec le Pangola (Digitaria decumbens). En zone humide et en stabulation libre, les niveaux d'ingestion très faibles sont en étroite relation avec le taux de MS du fourrage (15 % à 22) et induisent des croissances très médiocres (respectivement 14 et 8 g/j). Une étude menée au pâturage en zone sèche, selon 3 pressions de pâturage différentes, avec des chevrettes en croissance montre que, pour des quantités de Pangola "utile" proposées par animal et par jour (830, 1030 et 1770 g de MS de feuilles), la croissance observée durant 10 semaines est de 37, 46 et 52 g/j. Une comparaison entre le Pangola et le Pangola-Siratro (Macroptilium artropurpureum) est menée avec des mâles en croissance (8,5 à 20 kg). Le chargement varie de 900 et 1400 kg/ha de l'entrée à la sortie du système. Aucune différence n'est apparue, les GMQ moyens obtenus sont respectivement 51.7 + 26.0 g/j et 44.3 + 18.4 g/j (P > 0.05). Les facteurs de variations sont discutés. Le pâturage en avant des jeunes chevrettes sevrées leur permet d'avoir un meilleur choix alimentaire : elles ont deux fois plus de fourrage à leur disposition. En conséquence, la croissance est meilleure que celle des témoins (+ 44,9 vs + 30,7 g/j).
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13

Aumont, G., G. Saminadin, P. Cerneau, and A. Xandé. "Effects of sample preparation on nitrogen degradability of pangola grass (Digitaria decumbens) and tropical tree legumes." Journal of Agricultural Science 123, no. 1 (August 1994): 47–54. http://dx.doi.org/10.1017/s0021859600067769.

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SummaryThe effects of particle size on the nitrogen degradability of four tropical forages were studied in 1991 in Guadeloupe. Samples of pangola grass (Digitaria decumbens) 22 and 47 days old, Gliricidia sepium and Leucaena leucocephala were prepared as follows: grasses were (1) freshly cut with scissors to 0·5–1·0 cm in length and frozen at – 18 °C; or for later study were dried at 80 °C and ground to pass a (2) 0·5 mm, (3) 10 mm or (4) 20 mm screen. Nitrogen degradability (ND) was determined by placing samples in nylon bags with two different pore sizes (25 and 46 μm) which were then put into the rumen of cows for 2, 4, 8, 16, 24 and 48 h. The kinetics of nitrogen degradation were examined using Ørskov's model. Particle losses through the nylon bags, dry matter (DM) and nitrogen solubility of the samples were also measured in vitro. The sample preparation and the type of forage were the main sources of variation in the rapidly degradable nitrogen fraction, the slowly degradable nitrogen fraction, the degradation rate, the potentially degradable nitrogen fraction and ND. Nitrogen degradability was 55·8,46·7, 640 and 46·5% for pangola grass (at 22 and 47 days regrowth), Gliricidia and Leucaena samples, respectively. Mean ND was 47·9, 59·4, 56·1 and 49·6% for freshly cut and 0·5, 1·0 and 2·0 mm dried ground samples, respectively. Sample preparation had little effect on nitrogen solubility. For samples dried and ground at 0·5 and 1·0 mm, particle losses were 18·8 and 15·0% of DM, respectively. The insoluble but degradable fraction was 60·8, 51·9, 42·5 and 42·7% for freshly cut and 0·5, 1·0 and 2·0 mm dried ground samples, respectively. The freshly cut material appeared to be suitable for the estimation of ND in tropical forages.
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14

Ford, Clive W. "A feruloylated arabinoxylan liberated from cell walls of Digitaria decumbens (pangola grass) by treatment with borohydride." Carbohydrate Research 190, no. 1 (July 1989): 137–44. http://dx.doi.org/10.1016/0008-6215(89)84153-9.

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15

Britz, Steven J., Wayne E. Hungerford, and David R. Lee. "Photoperiodic Regulation of Photosynthate Partitioning in Leaves of Digitaria decumbens Stent." Plant Physiology 78, no. 4 (August 1, 1985): 710–14. http://dx.doi.org/10.1104/pp.78.4.710.

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16

Archimède, H., G. Aumont, G. Saminadin|, E. Deprès, P. Despois, and A. Xandé. "Effects of urea and saccharose on intake and digestion of a Digitaria decumbens hay by black belly sheep." Animal Science 69, no. 2 (October 1999): 403–10. http://dx.doi.org/10.1017/s1357729800050979.

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AbstractEffects of incorporation of urea and saccharose in diets, on intake and digestion by sheep of a 35-day-old pangola (Digitaria decumbens) hay, have been studied according to a 4 × 4 Latin-square design. Sixteen rams were given four diets: hay (C); hay plus urea (U, 23 g/kg hay); hay plus saccharose (S, 60 g/kg hay), hay plus urea and saccharose (SU). Acid-detergent fibre and crude protein (CP) content of the roughage were 395 and 78 g/kg dry matter (DM) respectively. Intake of hay (g DM per kg live weight0.75), supplemented with urea and sugar (42⋅9), was lower (F < 0.05) than with other diets (47.2, s.e. 1.6). The organic matter (OM) total tract and ruminal digestibility of the diet C, S, U and SU were 0.622, 0.590, 0.615 and 0.587 (s.e. 0.007); 0.361, 0.380, 0.378 and 0.345 (s.e. 0.015) respectively. Effective degradation and nylon bag kinetics of DM degradation were higher with U and SU compared with S or C. Few differences were observed between diets for ruminal concentration of volatile fatty acids. The ruminal ammonia concentrations were higher (P < 0.05) for the diets with urea than without urea (78 v. 215 mg/l). The efficiencies of the microbial synthesis (g nitrogen per kg OM fermented in the rumen) were, 23.6, 22.4, 24.9 and 29.3 (s.e. 1.7) for the diets C, U, S and SU respectively.Even though additional urea increased nitrogen availability for ruminal bacteria, urea supplementation did not affect significantly intake or digestion of the pangola hay of medium CP content used in this experiment.
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17

Ford, Clive W. "Comparative structural studies of lignin-carbohydrate complexes from Digitaria decumbens (pangola grass) before and after chlorite delignification." Carbohydrate Research 147, no. 1 (March 1986): 101–17. http://dx.doi.org/10.1016/0008-6215(86)85010-8.

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18

Whiteman, PC, NR Halim, BW Norton, and JW Hales. "Beef production from three tropical grasses in south-eastern Queensland." Australian Journal of Experimental Agriculture 25, no. 3 (1985): 481. http://dx.doi.org/10.1071/ea9850481.

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A grazing trial with beef cattle was conducted on three grasses, Paspalum plicatulum cv. Rodd's Bay, Brachiaria decumbens cv. Basilisk (signal grass) and Panicum maximum cv. Hamil, in the first year. P. maximum was replaced by Digitaria decumbens (pangola grass) in the second and third years. There were three stocking rates (3.0, 3.75, and 5.0 steers/ha), plots were fertilized with 300 kg N/ha, in two replicates. Animal liveweight gain was low; maximum values were 650 kg/ha for pangola grass, 640 kg/ha for signal grass and 400 kg/ha for P. plicatulum. Liveweight gain was only poorly correlated with rainfall, because low winter temperatures retarded pasture growth. Correlations between liveweight gain and individual green leaf percentage in each species were high, particularly for P. plicatulum, which had only 2% green leaf in winter. Weight loss on plicatulum was therefore high in winter, and overall performance poor, even though this species had the highest percentage of green leaf in summer. Signal grass showed a higher tolerance to grazing at 5.0 steers/ ha than the other grasses. Over most of the year, except in winter when only small amounts of green leaves were available, plicatulum had the lowest phosphorus percentage, sometimes below the 0.12% suggested as the critical dietary phosphorus percentage for cattle. Over all grasses, nitrogen and phosphorus concentrations were linearly related (r = 0.98). From this experiment, P. plicatulum was shown to be a poor grass for beef production and, for this grass and the other two species at this site, beef production using 300 N kg/ha could not be financially viable.
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19

Hunter, RA, and BD Siebert. "The effect of supplements of rumen-degradable protein and formaldehyde-treated casein on the intake of low-nitrogen roughages by Bos taurus and Bos indicus steers at different stages of maturity." Australian Journal of Agricultural Research 38, no. 1 (1987): 209. http://dx.doi.org/10.1071/ar9870209.

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The response in voluntary feed intake, firstly to supplements of rumen-degradable protein and then to additional supplements of formaldehyde-treated casein (FTC) was studied in Aberdeen Angus (Bos taurus) and Brahman (Bos indicus) steers fed long-chopped spear grass (Heteropogon contortus) and pangola grass (Digitaria decumbens). The intake responses were measured at four stages of maturity of the steers ranging from soon after weaning to near maturity. On diets deficient in nitrogen the magnitude of the intake response to rumen-degradable protein was greater in Angus than in Brahmans. With the exception of the Angus steers fed spear grass soon after weaning, there was no significant response to FTC with either diet beyond that achieved with rumen-degradable protein. From published values of the digestible protein supplied by the diets and the protein requirements of cattle for maintenance, it was calculated that pangola grass, prior to supplementation with FTC, supplied sufficient digestible protein for maintenance. On the other hand, that supplied by spear grass, prior to supplementation with FTC, was substantially below that required for maintenance. These experimental and calculated data are discussed in terms of factors limiting feed intake, and conclusions drawn about protein requirements for the expression of maximum feed intake of roughage diets.
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20

Hunter, R. A., and B. D. Siebert. "Utilization of low-quality roughage byBos taurusandBos indicuscattle." British Journal of Nutrition 53, no. 3 (May 1985): 649–56. http://dx.doi.org/10.1079/bjn19850074.

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1. In a number of experiments voluntary food intake of three low-quality roughages, either alone or supplemented with rumen-degradable nitrogen and sulphur and minerals, was measured in Brahman (Bos indicus) and Hereford (Bos taurus) steers. The chaffed hays were Spear grass (Heteropogon conform) (6.2 g N/kg organic matter (OM)), Pangola grass (Digitaria decumbens) (7.9 g N/kg OM), and Pangola grass (12.0 g N/kg OM). Rumen characteristics relating to rate of fluid outflow from the rumen were also determined.2. There was no significant difference between breeds in the dry-matter intakes of the unsupplemented diets which ranged from 11.3 to 17.8 g/kg body-weight (BW) by Herefords and from 11.8 to 16.1 g/kg BW by Brahmans.3. Supplementation of Spear grass with N and S significantly (P < 0.05) increased intake by Herefords (24%) but not by Brahmans. When the lower-N Pangola grass was supplemented there was a significant increase in intake by both breeds with the magnitude of the response in Herefords (42%) (P < 0.001) being greater than that in Brahmans (15%) (P < 0.05). The intakes of both the supplemented Spear grass and the lower-N Pangola diets were significantly (P < 0.05) greater by Herefords than Brahmans. There was no breed difference in intake when the higher-N Pangola grass was supplemented. Both breeds recorded an 8% intake response to supplementation, although the increase was only significant (P < 0.05) in Herefords.4. The mean retention time of fluid in the rumen on the unsupplemented Pangola grass diet of lower N content was 12.7 h in Brahmans compared with 17.5 h in Herefords (P < 0.01). When the higher-N Pangola was fed, both alone and supplemented, the mean retention times were similar on both diets (10.5 and 9.9 h for Herefords; 9.5 and 8.1 h for Brahmans for unsupplemented and supplemented diets respectively).5. Plasma urea concentrations were higher in Brahmans than in Herefords on all diets. Rumen ammonia concentrations were significantly (P < 0.001) higher in Brahmans than Herefords when the lower-N Pangola grass diet was unsupplemented.6. The intakes and the variable intake responses to supplementation between breeds and diets are discussed in relation to a number of animal and dietary factors.
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Tjandraatmadja, M., I. C. MacRae, and B. W. Norton. "Digestion by sheep of silages prepared from mixtures of tropical grasses and legumes." Journal of Agricultural Science 120, no. 3 (June 1993): 407–15. http://dx.doi.org/10.1017/s0021859600076577.

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SUMMARYFour silage diets were prepared from tropical grass and legume mixtures and fed to intestinally fistulated sheep to determine the sites and extent of digestion of the different silage components in the digestive tract. Pangola grass (Digitaria decumbens) was ensiled either alone or with the addition, 33% (w/w), of leucaena (Leucaena leucocephala cv. Cunningham), gliricidia (Gliricidia sepium) or cowpea (Vigna unguiculata cv. Caloona). All forages were grown at the University of Queensland farm in 1985. All silages were well preserved as indicated by low pH (< 4·1), ammonia N (< 9% total N), acetic acid (< 13 g/kg dry matter (DM)) and ethanol (< 19 g/kg DM) contents, and high DM (> 290 g/kg) and lactic acid (> 41 g/kg DM) contents. The inclusion of leucaena and gliricidia significantly increased the total N content of the silages. The addition of legumes at ensiling significantly increased rumen ammonia N (pangola 59 mg N/l, legume diets 110–115 mg N/l) and the proportion of propionic acid in rumen fluid. Sheep given pangola + leucaena silages had significantly higher DM intakes (66·3 g/kg W0·75 per day) than sheep given pangola and pangola + cowpea silages (52·4 and 53·2 g/kg W0·75 per day respectively). The inclusion of gliricidia significantly depressed silage intake (43·1 g/kg W0·75 per day). There were no significant effects of diet on DM (551–609 g/kg) and organic matter (550–612 g/rkg) digestibility. Sheep given pangola + leucaena silages had higher N intakes, N balances, rates and efficiencies of microbial N synthesis and total non-ammonia N (NAN) flows to the small intestine than did sheep given the other silages. Apparent degradabilities of silage N in the rumen were similar for all diets (0·491–0·559 g N/kg N intake), but sheep given pangola + leucaena silages had lower true (corrected for endogenous N) N degradabilities (0·648 g N/kg N intake) than those given the other diets (0·751–0·775 g N/kg N intake). The values obtained in this experiment were compared with those reported for temperate grass silages, and it was concluded that whilst the digestibility of tropical grass/legume silages was low, intakes and rumen fermentation characteristics were similar to those found for temperate grass silages.
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22

Almeida-M., Ricardo. "Productividad primaria de tres praderas de especies tropicales: pará (Brachiaria mutica), Grama amarga (Paspalum conjugatum) y Pangola (Digitaria decumbens)." Botanical Sciences, no. 41 (March 30, 2017): 3. http://dx.doi.org/10.17129/botsci.1240.

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23

Ford, C. W., and R. Elliott. "Biodegradability of mature grass cell walls in relation to chemical composition and rumen microbial activity." Journal of Agricultural Science 108, no. 1 (February 1987): 201–9. http://dx.doi.org/10.1017/s0021859600064273.

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SummaryCell walls from mature stems of three tropical grass species (Digitaria decumbens(pangola),Setaria anceps(cv. Kazangula) and sugar cane), and temperate barley straw, were analysed for lignin, carbohydrate, and the maj or acyl groups ferulate, ρ-coumarate and acetate. Samples were incubated in nylon bags in the rumen of sheep in a 4 x 4 latin-square design, and rates of disappearance of cellulose, hemicellulose, xylose, arabinose, ferulate, ρ-coumarate and acetate were determined during 60 h incubation. Interspecies differences in cell-wall chemistry appeared largely in the variable degree of acylation with p-coumaric acid (1·0–3·3%) and acetate (0·5–3·6%), and the high glucose concentration in the hemicellulose from pangola (17%) andSetaria(9%). Barley had much lower concentrations of these components than the tropical species. After 24 h incubation, losses of cellulose and acyl groups were greatest from pangola, whereas hemicellulose and its major components xylose and arabinose were degraded to the greatest degree from barley straw.Setariacell-wall components were generally more resistant to degradation than the other species. No relationship was found between the concentration of any cell-wall constituent and degradability measurements. Nor were changes in microbial population, indicated by measuring the accumulation of cystine on the fibres, related to the rate or degree of degradation of any of the measured cell-wall constituents. Lignin was fractionated with alkali into insoluble and soluble fractions. The latter (25–50% of original lignin) gave high interspecies correlations with the degradability of total hemicellulose and its component monosaccharides. It was concluded that variability in the biodegradability of the cell walls was more likely due toin situstructural features, such as cross-linking between polymers, than to the concentration of any particular cell-wall constituent.
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24

Silva, I. F., and J. Mielniczuk. "Sistemas de cultivo e características do solo afetando a estabilidade de agregados." Revista Brasileira de Ciência do Solo 22, no. 2 (June 1998): 311–17. http://dx.doi.org/10.1590/s0100-06831998000200017.

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Em um Latossolo Roxo de Santo Ângelo (RS), e em um Podzólico Vermelho-Escuro de Eldorado do Sul (RS), ambos com textura argilosa, submetidos o primeiro à exploração com cultivo convencional de trigo (Triticum aestivum L.) e soja (Glycine max L.) e sob setária (Setaria anceps L.), e o segundo à exploração com capim-pangola (Digitaria decumbens L.), siratro (Macroptilium atropurpureum L.), plantio direto com aveia (Avena bizantina L.)/milho (Zea mays L.) e área sem vegetação, foi realizado o presente trabalho durante a safra de verão (1990/1991), com o objetivo de avaliar a estabilidade e a agregação do solo sob diferentes sistemas de cultivo. Constatou-se, nessa avaliação, que as gramíneas perenes por meio do seu sistema radicular tiveram grande efeito na agregação e estabilidade dos agregados do solo e que os teores de carbono orgânico, de ferro e alumínio-oxalato, argila e grau de dispersão tiveram também efeitos na agregação do solo, porém insuficientes para explicar as variações entre o diâmetro médio ponderado dos agregados sob os diferentes sistemas de cultivo.
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Santos, A. C., I. F. Silva, J. R. S. Lima, A. P. Andrade, and V. R. Cavalcante. "Gramíneas e leguminosas na recuperação de áreas degradadas: efeito nas características químicas de solo." Revista Brasileira de Ciência do Solo 25, no. 4 (December 2001): 1063–71. http://dx.doi.org/10.1590/s0100-06832001000400028.

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Com o objetivo de avaliar a eficiência de duas leguminosas e duas gramíneas na melhoria das características químicas do solo (carbono orgânico, CTC efetiva e potencial e teores de P, K, Na, Ca, Mg, H + Al e pH do solo), considerando a profundidade e a posição de coleta das amostras, foi realizado experimento com arranjo fatorial em parcelas subdivididas, utilizadas anteriormente para estudos de perdas de solos por erosão, em um Nitossolo Vermelho eutrófico textura argilosa, localizado no município de Alagoinha (PB). Os tratamentos utilizados constituíram-se de duas leguminosas (feijão guandu - Cajanus cajan L. e siratro - Macroptilium atropurpureum L.), duas gramíneas (capim-pangola - Digitaria decumbens L. e capim-elefante - Pennisetum purpureum L.) e parcela desnuda (testemunha), com três repetições. A utilização das leguminosas e das gramíneas promoveu aumentos nos teores de carbono orgânico total e na capacidade de troca de cátions; promoveu, também, aumento nos teores de potássio, matéria orgânica e magnésio, principalmente na camada superficial. O maior acúmulo de liteira foi conseguido com o capim-elefante, sendo este acúmulo maior na posição inferior das parcelas em todos os tratamentos.
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ALEXANDRE, G., G. AUMONT, J. FLEURY, O. COPPRY, P. MULCIBA, and A. NEPOS. "Production semi-intensive au pâturage de caprins à viande en zone tropicale humide : le cas des cabris Créoles sur pangola (Digitaria decumbens) en Guadeloupe." INRAE Productions Animales 10, no. 1 (February 7, 1997): 43–53. http://dx.doi.org/10.20870/productions-animales.1997.10.1.3976.

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Dans la Caraïbe, le mode de production animale le plus répandu est l’élevage au pâturage. Différents travaux menés sur l’exploitation du pangola (Digitaria decumbens) par les chèvres Créoles à viande en Guadeloupe sont présentés. Le troupeau est conduit toute l’année au pâturage de façon intensive (conduite de la reproduction, prophylaxie, fertilisation, irrigation, charge animale). La production de chèvres en système allaitant valorise le système fourrager testé (1385 kg de sevrés/ha) et le système intensif permet l’expression du potentiel de ce génotype performant. L’augmentation du chargement de 1390 à 1980 kg de poids vif par hectare ne s’accompagne pas de baisses des performances de reproduction et d’allaitement mais d’une augmentation de la mortalité pré-sevrage de 7 à 10,5 %. Un mode de gestion rotatif basé sur l’âge de repousse du fourrage n’a pas permis d’améliorer la qualité pastorale du fourrage offert mais a sans doute accru le parasitisme gastro-intestinal des jeunes sous la mère. Une réduction notable des apports de concentrés aux mères (près de 46 % d’énergie totale) a pu être appliquée sans altérer leurs performances zootechniques. Les performances à l’herbe des jeunes en croissance sont de près de 37 g/j de croissance du sevrage jusqu’à l’âge de 11 mois. L’élevage des chevreaux mâles ou femelles sur pâturage intensif de pangola produit en moyenne 1130 kg de croît/ha/an. Un enrichissement de la prairie en légumineuse n’a pas permis d’augmenter de façon sensible la croissance des jeunes boucs. Un mode de pâturage en avant de jeunes chevrettes au sortir du sevrage a permis d’améliorer leurs résultats d’élevage. Les méfaits de l’intensification fourragère sont discutés : mauvaise maîtrise agronomique des pâtures, accumulation de biomasse fourragère résiduelle, dégradation progressive de la valeur pastorale des prairies, augmentation de l’incidence parasitaire. L’intérêt de promouvoir une intensification raisonnée des systèmes de pâturages tropicaux est présenté.
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27

Tjandraatmadja, M., I. C. MacRae, and B. W. Norton. "Effect of the inclusion of tropical tree legumes, Gliricidia sepium and Leucaena leucocephala, on the nutritive value of silages prepared from tropical grasses." Journal of Agricultural Science 120, no. 3 (June 1993): 397–406. http://dx.doi.org/10.1017/s0021859600076565.

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SUMMARYSilages were prepared from the tropical grasses, pangola grass (Digitaria decumbens) and setaria (Setaria sphacelata), with the addition of molasses (4% w/w) and/or leaves (33%) from the leguminous trees leucaena (Leucaena leucocephala) and gliricidia (Gliricidia sepium). All forages were grown at the University of Queensland farm in south eastern Queensland during 1985. These silages, together with hays made from these grasses and sorghum silage (13 diets) were fed to sheep to assess their nutritive value. All silages were well preserved, as indicated by low pH (3·5–4·4), low ammonia N (26–57 g/kg total N) and high lactic acid (73–95% total acids) contents. The addition of legumes increased both the dry matter (DM) and total N (TN) contents of silages to the same extent as the addition of both legumes and molasses at ensiling. Sheep given silages prepared from pangola grass and legumes (±molasses) consumed similar DM intakes (22·9–25·4 g/kg0·75 per day) as sheep given pangola grass hay (23·9 g/kg0'75 per day). Silage made from pangola grass + molasses was of low palatability (16·1 g/kg0·75 per day). The digestibilities of silage DM (DMD) and its fibrous components were significantly (P<0·05) lower (DMD 53·3–60·6%) than that of pangola hay (DMD 64·7%). Silages and hay made from setaria, and sorghum silage, were of lower nutritive value than those from pangola grass. The addition of leucaena and molasses increased silage DM intakes (21·1 g/kg0·75 per day) above those for setaria hay and setaria + molasses silage (16·7 and 19·0 g/kg0·75 per day respectively). The intakes of silages made from gliricidia (17·1 g/kg0·75 per day) were significantly (P <0·05) improved when molasses was included at ensiling (21·8 g/kg0·75 per day). The digestibilities of silage DM were significantly (P<0·05) higher (DMD 53·6–60·4%) than that of setaria hay (DMD 40·6). Liveweight change in sheep was significantly (P<0·05) correlated with intakes of digestible DM (r2= 0·74) and with N intake (r2= 0·82). The inclusion of legumes in the silages increased N retention and, for setaria silages, also increased rumen ammonia concentration. It was concluded that tropical grasses can be effectively ensiled by the addition of legumes alone and, with the exception of setaria/gliricidia silages, the resultant silages were of sufficiently high quality to merit their use in tropical animal production systems.
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Mahieu, Maurice. "Production ovine sur pâturage de Digitaria decumbens Stent. irrigué ou non. Résultats technico-économiques." Revue d’élevage et de médecine vétérinaire des pays tropicaux 44, special (May 1, 1991): 17–22. http://dx.doi.org/10.19182/remvt.9238.

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Entre 1981 et 1985, la SECI a conduit un programme destiné à évaluer l'impact de l'irrigation sur la production de viande, avec pour supports le Digitaria decumbens Stent. et le mouton créole. Les résultats des essais indiquent que l'irrigation permet de : passer de 11 à 40 brebis par hectare, et de produire 1090 contre 230 kg de mouton sevré à l'hectare et par an, grâce à la régularisation de la production fourragère et à l'amélioration induite des performances individuelles des animaux; s'affranchir des risques techniques (et économiques) liés aux saisons sèches prolongées; d'améliorer la rentabilité de l'élevage, d'où, pour assurer un même revenu, diminution du capital et de la surface nécessaires.
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29

Haddad, Cláudio Maluf, José Alfredo Salinas Daiub, Flávio Geraldo Ferreira Castro, and Luis Fernando Monteiro Tamassia. "Produção de matéria seca, valor nutritivo e a maturidade de Digitaria decumbens Stent. cv. transvala." Scientia Agricola 56, no. 3 (July 1999): 681–88. http://dx.doi.org/10.1590/s0103-90161999000300024.

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Este experimento teve como objetivo avaliar a produção de matéria seca, a digestibilidade in vitro e a variação na composição químico-bromatológica e mineral do capim-Transvala (Digitaria decumbens Stent. cv. Transvala) em função da idade de corte. O delineamento estatístico adotado foi inteiramente casualizado, com seis tratamentos e cinco repetições. Os tratamentos constaram de seis idades de corte, com intervalo de 10 dias entre cada corte, sendo que o primeiro corte foi realizado 20 dias após o corte de uniformização. A produção de matéria seca aumentou de forma linear (P < 0,05) com o avanço da idade da planta e a digestibilidade in vitro da matéria seca e o teor de proteína bruta decresceram quadraticamente (P < 0,05). Inversamente, o teores de fibra em detergente neutro e fibra em detergente ácido aumentaram de forma quadrática (P < 0,05) com a idade da planta e os teores de fósforo, potássio, cálcio, magnésio e enxofre sofreram decréscimos quadráticos (P < 0,05). As concentrações de Cu e Zn diminuíram de forma quadrática (P < 0,05) com o avanço da idade da planta, enquanto o teor de Mn aumentou de forma quadrática. A análise dos resultados permitiu concluir que no manejo do capim do capim-Transvala deve ser adotado o intervalo entre cortes de 30 a 40 dias, levando-se em conta os valores dos níveis dos parâmetros analisados e as necessidades nutricionais dos animais.
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30

Gonçalves, Geógenes da Silva, Gabriel Jorge Carneiro de Oliveira, Soraya Maria Palma Luz Jaeger, Ronaldo Lopes Oliveira, Jamille Oliveira Campos, and Letícia Santos Rezende. "Desempenho de cordeiros alimentados com dietas contendo sal forrageiro de espécies vegetais xerófitas." Revista Brasileira de Zootecnia 37, no. 12 (December 2008): 2185–90. http://dx.doi.org/10.1590/s1516-35982008001200016.

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Este trabalho foi realizado com o objetivo de avaliar o uso de sal forrageiro sobre os consumos de sal forrageiro (CSF) e de feno de capim-pangola (Digitaria decumbens) e os consumos de matéria seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), hemicelulose (HCEL), lignina e água (AGU), além do ganho de peso diário (GPD) e da conversão alimentar de cordeiros em confinamento. Os sais forrageiros foram compostos de farelos de fenos (90%) das dicotiledôneas, sal mineral (5%) e milho triturado (5%). Utilizaram-se 30 animais machos não-castrados, mestiços Santa Inês, distribuídos em delineamento inteiramente casualizado, com seis tratamentos (sal mineral; sal forrageiro de leucena, Leucaena leucocephala; sal forrageiro da parte aérea de mandioca, Manihot esculenta; sal forrageiro de feijão-bravo, Macroptilium bracteatum; sal forrageiro de barriguda, Ceiba samauma; e sal forrageiro de quipé, Piptadenia moniliformis), cada um com cinco repetições. Os sais forrageiros de leucena e da parte aérea de mandioca promoveram melhores resultados de desempenho, ganhos de pesos totais e conversão alimentar, o que evidencia o potencial dessas forrageiras para formulação de sal forrageiro, utilizado na suplementação de dietas para cordeiros em confinamento.
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31

Lyra Netto, Angela M. C. de, Armando D. de Araújo, Jandira F. Warumby, and Irene M. R. Marques. "Flutuação populacional da cigarrinha de pastagens Deois schach (Fabricius, 1787) (Homoptera-Cercopidae) em capim pangola (Digitaria decumbens) no estado de Pernambuco." Anais da Sociedade Entomológica do Brasil 18, no. 1 (June 1, 1989): 33–41. http://dx.doi.org/10.37486/0301-8059.v18i1.565.

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32

Hunter, R. A. "The effect of the α2-adrenergic agonist, guanfacin, on the energy metabolism of steers fed on low-quality-roughage diets." British Journal of Nutrition 67, no. 3 (May 1992): 337–43. http://dx.doi.org/10.1079/bjn19920039.

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The effect of the α2-adrenergic agonist, guanfacin, on the energy metabolism, feed intake and live weight (LW) change of steers was studied in three experiments. In the first, the metabolic rate of twelve steers was measured after a 72 h fast. The next day, after a 96 h fast, six steers were injected intramuscularly with 15 mg guanfacin in sterile saline (9 g sodium chloride/l) and six with sterile saline alone, and metabolic rate was measured again. Treatment significantly (P < 0.01) lowered metabolic rate by approximately 20% (53.9 v. 66.8 kJ/kg per d). In the second experiment twelve steers were fed on long-chopped, low-quality roughage (Pangola grass (Digitaria decumbens) hay) ad lib. for 6 weeks. Six steers were continuously infused through a jugular catheter with 15 mg guanfacin/d (about 40 μg/kg LW) in sterile saline. The other six served as controls. There was no significant effect of treatment on feed intake (g dry matter (DM)/kg LW) or the rate of LW loss. Treatment significantly (P < 0.05) increased the retention time of fluid (17.9 v. 22.1 h) in the alimentary tract. In the final experiment twenty-three steers were divided into four treatment groups and fed on long-chopped, low-quality roughage (Pangola hay). Treated animals were continuously infused with guanfacin at the rate of 20, 40 or 80 μg/kg LW per d. Control steers were not infused. At the end of the 6-week feeding period metabolic rate was measured after a 72 h fast. Regardless of dose, guanfacin significantly (P < 0.01) lowered metabolic rate. Feed intake was not significantly affected by treatment but the rate of LW loss was significantly (P < 0.05) less in treated steers.
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Galgal, K. K., N. P. McMeniman, and B. W. Norton. "Effect of copra expeller pellet supplementation on the flow of nutrients from the rumen of sheep fed low quality pangola grass (Digitaria decumbens)." Small Ruminant Research 15, no. 1 (December 1994): 31–37. http://dx.doi.org/10.1016/0921-4488(94)90056-6.

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34

MAHIEU, M., G. AUMONT, Y. MICHAUX, G. ALEXANDRE, H. ARCHIMÈDE, M. BOVAL, and M. THÉRIEZ. "L’association d’ovins et de bovins sur prairies irriguées en Martinique." INRAE Productions Animales 10, no. 1 (February 7, 1997): 55–65. http://dx.doi.org/10.20870/productions-animales.1997.10.1.3977.

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Les performances animales et les productions par unité de surface de cinq systèmes d’exploitation de prairies irriguées de pangola (Digitaria decumbens) ont été étudiées durant deux années en Martinique (FWI) : agneaux ou agnelles "Martinik" en croissance pâturant seuls, génisses Brahman en croissance pâturant seules, agneaux ou agnelles associés aux bovins. Les charges en poids métabolique (PM=PV0,75) ont été identiques entre les systèmes et ont varié entre 488 et 536 kgPM/ha. L’association de bovins avec des ovins a permis une augmentation de la croissance des ovins, en particulier pour les mâles (+ 13 %). L’association avec des ovins a également conduit à une augmentation (non significative) de 10 % de la croissance des génisses. L’association des bovins et ovins a augmenté la production de viande à l’hectare de 18 à 25 %. Cette augmentation de la production a pu être reliée à une diminution de l’infestation parasitaire des ovins (en particulier pour les agneaux) par Haemonchus contortus, une diminution de la biomasse fourragère sur les parcelles et une amélioration de la qualité du disponible fourrager (ratio feuilles/tiges). Les bilans de production fourragère ont montré que l’association des bovins et des ovins au pâturage permet de limiter les pertes d’azote dans la biomasse inutilisée. Cependant, la maîtrise de la fertilisation azotée reste une des contraintes majeures pour l’optimisation des systèmes pâturés intensifs en milieu tropical humide.
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Ospina R., Oscar, Hector José Anzola Vasquez, Olber Ayala D., Andrea Baracaldo M., Juan Arévalo C., and Pedro Lozada W. "Comparación de la fibra detergente neutra en gramíneas, calculada mediante algoritmo de análisis de imágenes rojo, verde y azul vs espectroscopia del infrarrojo cercano." Revista de Investigaciones Veterinarias del Perú 32, no. 1 (February 26, 2021): e17498. http://dx.doi.org/10.15381/rivep.v32i1.17498.

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El trabajo estuvo orientado a evaluar la precisión del algoritmo de análisis de imágenes Red, Green, Blue (RGB) incluido en el software TaurusWebs V2017® para el cálculo del porcentaje de fibra detergente neutra (FDN) en la materia seca de gramíneas, a partir de imágenes de las praderas tomadas por un dron con cámara RGB. Los resultados fueron comparados con los valores de FDN calculados con espectroscopia del infrarrojo cercano (NIRS). Se tomaron 42 muestras para NIRS: 18 de gramíneas de trópico alto en Cundinamarca: kikuyo (Pennisetum clandestinum), falsa poa (Holcus lanatus) y pasto brasilero (Phalaris arundinacea) y 24 de trópico bajo en Tolima, Colombia: pangola (Digitaria decumbens), pará (Brachiaria mutica), bermuda (Cynodon dactylon) y colosuana (Bothriochloa pertusa). Los resultados se compararon contra 180 evaluaciones hechas con el algoritmo de las imágenes de las mismas gramíneas donde se tomaron las muestras para NIRS. Las pruebas de correlación de Kendall y de Spearman fueron significativas (p<0.05), con una asociación de rho=0.81 para la prueba de hipótesis de Kruskal Wallis (p> 0.05). No hubo diferencias significativas en los valores de FDN bajo las dos metodologías y según la prueba de Wilcoxon las medianas de la FDN calculada por NIRS vs. las del algoritmo son iguales. En conclusión, la información generada con el algoritmo se puede utilizar para trabajos de análisis del FDN en gramíneas.
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Ospina R., Oscar, Héctor Anzola Vásquez, Olber Ayala Duarte, and Andrea Baracaldo Martínez. "Validación de un algoritmo de procesamiento de imágenes Red Green Blue (RGB), para la estimación de proteína cruda en gramíneas vs la tecnología de espectroscopía de infrarrojo cercano (NIRS)." Revista de Investigaciones Veterinarias del Perú 31, no. 2 (June 20, 2020): e17940. http://dx.doi.org/10.15381/rivep.v31i2.17940.

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El presente trabajo estuvo orientado a evaluar la precisión del algoritmo de análisis de imágenes Red, Green, Blue (RGB), incluido en el software TaurusWebs ®, que permite calcular el porcentaje de proteína cruda de la materia seca (%PC) de las gramíneas a partir de imágenes de las praderas tomadas por un dron acoplado con cámaras RGB. Se compararon las mediciones del %PC calculadas por el algoritmo frente a un referente, Near Infrared Reflectance Spectroscopy (NIRS), del laboratorio de Corpoica (Agrosavia), calibrado para gramíneas. Se tomaron 42 muestras para NIRS, 18 de gramíneas de trópico alto en Cundinamarca: kikuyo, Pennisetum clandestinum; falsa poa, Holcus lanatus; pasto brasilero, Phalaris arundinacea y 24 de trópico bajo en Tolima, Colombia: pangola, Digitaria decumbens; pará, Brachiaria mutica; bermuda, Cynodon dactylon y colosuana, Bothriochloa pertusa. Los resultados del NIRS se compararon contra las evaluaciones hechas con el algoritmo de las imágenes de las gramíneas provenientes del mismo potrero donde se tomaron las muestras. Los resultados fueron comparados usando las pruebas no paramétricas de correlación de Kendall, rho=0.83 y de Kruskal Wallis. No se encontraron diferencias entre el resultado del %PC de las gramíneas medida por NIRS vs el %PC medida por el algoritmo de análisis de imágenes RGB. En conclusión, la información generada con el algoritmo se puede utilizar para trabajos de análisis del %PC en gramíneas.
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Moss, RJ, and IK Goodchild. "Rearing dairy calves on irrigated tropical pastures. 2. Effect of levels of maize and cottonseed meal on growth of weaner calves." Australian Journal of Experimental Agriculture 32, no. 5 (1992): 581. http://dx.doi.org/10.1071/ea9920581.

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Fifty-two Australian Friesian Sahiwal (AFS) calves were weaned at 70 kg liveweight onto irrigated and fertilised couch (Cynodon dactylon)- pangola (Digitaria decumbens) pastures in North Queensland. They were offered supplements of maize (9.5% crude protein) or a mixture of 5 maize: 1 cottonseed meal (15% crude protein) fed at 1.0 or 1.5 kg/calf.day in a 2 x 2 factorial experiment. Calves entered the experiment after weaning and were removed when they exceeded 130 kg liveweight. More calves were reared in spring and summer than in autumn and winter, and stocking rate varied between 20 weaners/ha (summer) and 12.5 weaners/ha (winter). Additional supplementation with maize above 1 kg/calf.day did not increase liveweight gain in calves of up to 130 kg liveweight. Inclusion of cottonseed meal in the supplement increased calf growth at the higher level of supplementation (P<0.01) and calves reached 130 kg liveweight 2 weeks earlier than calves fed maize (P<0.05). The interaction of level of feeding with protein content of the supplement was significant at P = 0.058. Calves reared in the wet season gained less (0.47 kg/day) than calves reared in the dry season (0.60 kg/day) (P<0.01). Animal responses to supplementary feeding were similar in both seasons, but even at high levels of supplementation, and with added protein, calves reared in the wet season did not maintain desired growth rates over this period.
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Díaz Lezcano, Maura Isabel, Cynthia Carolina Gamarra Lezcano, Susana Ruiz Diaz, and Mirtha Vera de Ortiz. "Contenido de materia orgánica en suelos de sistemas silvopastoriles establecidos en el Chaco Central paraguayo." Revista de la Sociedad Científica del Paraguay 25, no. 2 (November 11, 2020): 131–43. http://dx.doi.org/10.32480/rscp.2020.25.2.131.

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El sistema silvopastoril se caracteriza por asociación de ganadería, árboles y pastura, la interacción entre estos componentes aporta beneficios tanto al suelo, como a la pastura, al ganado y a los árboles y permite un aumento en la productividad y la diversificación de la producción. Para conocer la influencia del componente arbóreo del sistema silvopastoril sobre el contenido de materia orgánica del suelo se llevó a cabo un estudio exploratorio en propiedades privadas ubicadas en los Departamento de Boquerón y Presidente Hayes del Chaco Central paraguayo. Se instalaron 8 parcelas permanentes de 1 ha cada una en las que se midieron y registraron todos los individuos de algarrobo (Prosopis spp), se identificaron y extrajeron muestras de pastura de subparcelas de 1m2 que se ubicaron bajo la copa de los árboles y fuera de la copa para comparar la biomasa de la pastura, se extrajeron muestras de suelo bajo las condiciones mencionadas y a dos profundidades, de 0 a 10 cm y de 10 a 30 cm, para comparar el contenido de materia orgánica, carbono y nitrógeno. El componente arbóreo estaba integrado por algarrobo blanco (Prosopis alba) y algarrobo negro (Prosopis nigra) asociados a pastura implantada, Gatton panic (Panicum máximum cv Gatton panic) pasto Pangola (Digitaria decumbens) y pasto Buffel (Cenchrus ciliaris) mayoritariamente. No se registraron diferencias significativas en el contenido de materia orgánica, carbono y nitrógeno entre condiciones de sol y de sombra, pero sí al variar la profundidad. Bajo las condiciones del presente estudio no se registró una influencia significativa del componente arbóreo sobre el contenido de materia orgánica.
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Vezzani, Fabiane Machado, and João Mielniczuk. "Agregação e estoque de carbono em argissolo submetido a diferentes práticas de manejo agrícola." Revista Brasileira de Ciência do Solo 35, no. 1 (February 2011): 213–23. http://dx.doi.org/10.1590/s0100-06832011000100020.

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A estrutura física é uma propriedade essencial para que o solo cumpra adequadamente suas funções e tenha qualidade. Com o objetivo de avaliar a contribuição de práticas de manejo na recuperação da agregação de um solo fisicamente degradado, estudou-se a distribuição de agregados estáveis em água e partículas simples em classes de diâmetro (9,51-4,76; 4,76-2,00; 2,00-0,25; 0,25-0,053; < 0,053 mm) e o estoque de C na camada superficial de 0-7,5 cm de um Argissolo Vermelho distrófico típico da Depressão Central do Rio Grande do Sul sob sistemas de manejo. Em parcelas experimentais com 17 anos, avaliaram-se os sistemas: solo mantido sem plantas e sem revolvimento (Descoberto); plantio direto de Lablab purpureus e milho (Zea mays) (Lablab/m); plantio direto de Cajanus cajan e milho (Guandu/m); e pastagem perene de Digitaria decumbens (Pangola). Em parcelas experimentais com 15 anos, avaliaram-se os sistemas: preparo convencional e plantio direto de Avena strigosa e milho (pc a/m e pd a/m, respectivamente) e Avena strigosa + Vicia sativa e milho + Vigna unguiculata (pc av/mc e pd av/mc, respectivamente). Avaliaram-se, também, área de lavoura de grãos em preparo convencional conduzida por 30 anos (Lavoura) e área de campo nativo (CN), representando a condição degradada e o ecossistema nativo deste solo, respectivamente. As avaliações foram realizadas em amostras de solo indeformadas coletadas em duas épocas (setembro de 1999 e setembro de 2000), compondo seis repetições por sistema de manejo. Os dados foram analisados por meio da análise de variância, e o teste de Tukey (5 %) foi utilizado para verificar as diferenças entre os sistemas de manejo. O CN apresentou 76,4 % de solo agregado, distribuídos em 63,8 % de macroagregados e 23,6 % de partículas simples, com estoque de C de 20,0 Mg ha-1 na profundidade de 0-7,5 cm. O uso agrícola com revolvimento intenso do solo e baixa adição de resíduos (sistema Lavoura) reduziu a proporção de solo agregado para 49,9 % e aumentou a de partículas simples para 50,1 %. O estoque de C reduziu para 11,8 Mg ha-1 na profundidade de 0-7,5 cm. A partir dessa condição, o sistema sem revolvimento de solo, com maior diversidade de espécies de plantas e grande adição de resíduos (pd av/mc) elevou, em 15 anos, a proporção de solo agregado para 70,7 %, e a dos macroagregados, para 53,5 %. A pastagem perene (Pangola) elevou a proporção de solo agregado para 74,1 % e a dos macroagregados para 61,8 %, igualando-se ao CN. Os sistemas pd av/mc, Guandu/m e Lablab/m recuperaram os estoques de C no nível do CN. No entanto, a Pangola, que apresentou os maiores índices de agregação do solo, teve o estoque de C inferior ao desses sistemas, enfatizando a ação positiva do sistema radicular denso na recuperação da agregação do solo.
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40

Dorow, Rubens, and Fernando Luiz Ferreira de Quadros. "DESEMPENHO DE TERNEIROS DESMAMADOS PRECOCEMENTE E SUBMETIDOS A DIFERENTES SISTEMAS DE ALIMENTAÇÃO." Ciência Rural 24, no. 2 (1994): 411–13. http://dx.doi.org/10.1590/s0103-84781994000200034.

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RESUMO Este experimento foi conduzido na Fazenda Rincão em Cachoeira do Sul, RS; em convênio com a EMATER-RS e o Departamento de Zootecnia da Universidade Federal de Santa Maria, com o objetivo de avaliar o desempenho de temeiros de corte, medido em ganho de peso vivo, desde o desmame aos 90 dias até um ano de idade, quando submetidos a sistemas de alimentação baseados em pastagens naturais, pastagens de Digitaria decumbens Stent., Pennisetum americanum (L) Schum. e Avena strigosa Schreb., combinadas entre si. Avaliou-se a qualidade e disponibilidade de matéria seca das pastagens associando-as ao desempenho dos temeiros desmamados aos 90 dias. Observou-se, nas condições em que foi realizado o experimento, que os temeiros alimentados com pastagens de milheto no verão e aveia no inverno, atingiram 187,75kg de peso vivo médio aos 12 meses de idade. As condições climáticas adversas do período experimental e o manejo animal impostos na Fazenda Rincão contribuíram para a redução na disponibilidade de matéria seca das pastagens, influenciando diretamente o desempenho dos animais.
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41

Tomkins, N. W., N. P. McMeniman, and R. C. W. Daniel. "Voluntary feed intake and digestibility by red deer (Cervus elaphus) and sheep (Ovis ovis) of pangola grass (Digitaria decumbens) with or without a supplement of leucaena (Leucaena leucocephala)." Small Ruminant Research 5, no. 4 (September 1991): 337–45. http://dx.doi.org/10.1016/0921-4488(91)90071-w.

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42

Margan, DE, NM Graham, DJ Minson, and TW Searle. "Energy and protein values of four forages, including a comparison between tropical and temperate species." Australian Journal of Experimental Agriculture 28, no. 6 (1988): 729. http://dx.doi.org/10.1071/ea9880729.

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Artificially dried grass of 2 tropical species (Setaria spacelata and Digitaria decurnbens) from which most of the stem had been removed, and a temperate grass (Loliurn perenne) grown under the same subtropical conditions, were compared for energy and protein value. Data for a temperate clover hay (Trifolium resupinatum) that was tested concurrently are included because they provide useful contrasts. Each was evaluated by measuring energy, nitrogen (N) and carbon balances in 4 adult sheep at 2 levels of intake (ad libitum and near energy maintenance) and during fasting. The 3 grasses had similar leaf content (76-83%) and the clover much less (60%). The tropical forages had similar chemical composition but they contained less crude protein (10%) than the ryegrass (L. perenne) (1 5%) and more cell wall constituents (63-66% v. 58%). The clover had the most crude protein (19%) and the least cell walls (38%); it also was highest in carbohydrates, pectin and heat of combustion. Voluntary intakes of the setaria, pangola (D. decumbens) and ryegrass were similar and 20-30% lower than the intake of clover. Digestibilities of dry matter (DM), organic matter (OM) and energy were similar for the grasses and 8 percentage units lower than for the clover whereas digestibility of crude protein differed between the tropical and temperate species, the latter having digestibilities 12-15 units greater. Digestibility of cell walls did not vary. The metabolisable energy (ME) values of the grasses at maintenance were 8.3-8.5 MJ/kg DM while that of clover was 10.1; at maximum intakes, corresponding ME values were 7.9 and 10.0 MJ/kg DM. Net availability of ME for gain was 0.42 for the tropical grasses and the persian clover and 0.36 for the ryegrass. By contrast, the tropical forages supported higher gains of N relative to N supply than did the temperate forages because urinary N loss was not affected by intake of the tropicals; these differences in N gain were drastically reduced when gain was expressed in relation to ME. These results do not support the contention that forages of tropical species have a lower energy value per kg than temperate forages of similar composition. Indeed, the tropical species tested here appear to have had an ideal balance of energy and protein insofar as efficiency of use of digestible N was close to 100% and their energy values were commensurate with their chemical composition.
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López-Herrera, Michael, Rodolfo WingChing-Jones, and Augusto Rojas-Bourillon. "Bromatología de ensilados de corona de piña con pulpa de cítricos, heno y urea." Agronomía Mesoamericana 27, no. 1 (December 9, 2015): 37. http://dx.doi.org/10.15517/am.v27i1.21876.

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<p class="p1">El objetivo de esta investigación fue determinar las características nutricionales de los ensilados de mezclas de corona de la piña con inclusión de pulpa de cítricos deshidratada y heno, con niveles crecientes de urea. El experimento fue realizado entre los meses de mayo a setiembre del 2013 y las coronas provenían de Guápiles, Costa Rica. Estas fueron picadas hasta obtener una partícula promedio de 3 cm, y colocadas en bolsas de empaque al vacío a las que se les agregó, urea (0;0,5;1,0;1,5% p/p en base fresca), dos fuentes altas en materia seca: heno (H) de pasto Transvala (<em>Digitaria decumbens</em>, Stent., cv. Transvala) y pulpa de cítricos deshidratada (PCD) ambos a un nivel de inclusión (10% p/p en base fresca), y un único nivel de melaza (3% p/p) e inóculo bacterial por fermentación de melaza con suero de leche (1 l/t). Además se preparó una muestra sin aditivos como control. El heno aumentó el contenido de materia seca y todos los componentes de la fibra, pero redujo el contenido de proteína cruda (PC), carbohidratos no fibrosos y nutrimentos digestibles totales. Cuando se usó PCD, se redujo la fracción fibrosa, lo que aumentó la digestibilidad de la mezcla ensilada. El uso de urea aumentó el contenido de PC y redujo el nivel de nitrógeno ligado a la fibra por un efecto de dilución. Se estimó que los materiales ensilados podrían producir 0,43-1,89 kg leche/vaca, al consumir 5 kg material verde (MV)/animal; 0,86-3,77 kg leche/vaca, al consumir 10 kg MV/animal; 1,29-5,66 kg leche/vaca, al consumir 15 kg MV/animal.</p>
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44

"Pangola stunt virus. [Distribution map]." Distribution Maps of Plant Diseases, no. 2) (August 1, 2001). http://dx.doi.org/10.1079/dmpd/20066500434.

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Abstract A new distribution map is provided for Pangola stunt virus Viruses: Family Reoviridae: Genus Fijivirus Hosts: Digitaria decumbens and other Digitaria spp. Information is given on the geographical distribution in ASIA, Malaysia, Peninsular Malaysia, Sabah, Sarawak, Taiwan, SOUTH AMERICA, Brazil, French, Guiana, Guyana, Peru, Suriname, Venezuela, OCEANIA, Australia, New South Wales, Queensland, Fiji.
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Sánchez-Santillán, Paulino, Nicolas Torres-Salado, Jeronimo Herrera-Pérez, Adelaido R. Rojas-García, María A. Maldonado-Peralta, and Marco A. Ayala-Monter. "In vitro gas and methane production and dry matter degradation of pumpkin (Cucurbita argyrosperma) silages with pangola grass (Digitaria decumbens) hay." Agro Productividad 13, no. 11 (December 8, 2020). http://dx.doi.org/10.32854/agrop.v13i11.1786.

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Objetivo: Determinar la producción de gas, metano y degradación de la materia seca in vitro de ensilados elaborados con cascara y pulpa de calabaza (CPC; Cucurbita argyrosperma), heno de pasto pangola (Digitaria decumbens) y como aditivos urea y dos porcentajes de inclusión de melaza fermentados durante 14 y 21 días. Metodología: Los ensilados (2 Kg) fueron: E1 = 72.5% de CPC, 22.5% de pasto pangola, 3% de melaza y 2% de urea; E2 = 72.5% de CPC, 19.5% de pasto pangola, 6% de melaza y 2% de urea. Ambos ensilados se fermentaron por 14 y 21 días. Se evaluó la producción de gas, metano (CH4), conteo de bacterias totales y degradación de materia seca (DEGMS). El diseño experimental fue un diseño completamente al azar con arreglo factorial 2 x 2 con tipos de ensilado y tiempo de fermentación como factores. Resultados: El E1 a los 21 d mostró la menor producción de gas a las 72 h (46.96 mL g-1 MS) y menor DEGMS (35.78%; p ? 0.05). La producción de CH4 y conteo de bacterias totales no mostraron diferencias (p > 0.05) entre tipos de ensilado, ni tiempos de fermentación. Limitaciones del estudio: La inclusión de 3% de melaza con un tiempo de fermentación de 21 días presentó la menor producción de gas y degradación de la materia seca en ensilados con cascara y pulpa de calabaza y heno de pasto pangola. Conclusiones: Los ensilados elaborados con cascara y pulpa de calabaza son una alternativa viable para conservar y producir alimento para rumiantes en la época de sequía; así mismo usar adecuadamente materiales potencialmente contaminantes como la cascara y pulpa de calabaza.
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46

Gamarra, Cynthia, Maura Isabel Díaz Lezcano, Mirtha Vera de Ortíz, María Del Pilar Galeano, and Antero José Nicolás Cabrera Cardús. "Relación carbono-nitrógeno en suelos de sistemas silvopastoriles del Chaco paraguayo." Revista Mexicana de Ciencias Forestales 9, no. 46 (March 7, 2018). http://dx.doi.org/10.29298/rmcf.v9i46.134.

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El sistema silvopastoril permite que la producción ganadera sea más sustentable, porque la interacción entre sus componentes aporta beneficios al suelo, a la pastura, al ganado y a los árboles; además de, un aumento en la productividad y la diversificación de la producción. Para conocer las características de dichos sistemas, se llevó a cabo un estudio en propiedades privadas ubicadas en el Chaco Paraguayo, donde se instalaron ocho parcelas permanentes de 1 ha cada una, en las que se midieron todos los individuos de Prosopis spp. (algarrobo), se identificaron y extrajeron muestras de pastura de subparcelas situadas bajo la copa de los árboles y fuera de ella para comparar su biomasa; también se obtuvieron muestras de suelo en las mismas condiciones, a dos profundidades: de 0 a 10 cm y de 10 a 30 cm, con el propósito de comparar el contenido de materia orgánica y la Relación Carbono/Nitrógeno (C/N). El componente arbóreo estaba integrado por Prosopis alba (algarrobo blanco) y Prosopis nigra (algarrobo negro) asociados a pastura cultivada compuesta en forma mayoritaria por Panicum maximum cv Gatton panic (Gatton panic), Digitaria decumbens (pasto pangola) y Cenchrus ciliaris (pasto buffel). La presencia de los algarrobos influyó sobre la biomasa de la pastura, pues sus registros fueron mayores bajo las copas que fuera de estas. La materia orgánica en el suelo no presentó diferencias significativas entre condición de sol y de sombra, pero sí al variar la profundidad; en cambio, la Relación C/N no varió en ninguna de las condiciones.
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47

Villagra-Mendoza, Karolina, Daniela Brenes-Cano, and Natalia Gómez-Calderón. "Efecto del balanceo de cargas en los ejes de tractores agrícolas sobre la eficiencia de labranza y las propiedades físico-mecánicas de un suelo vertisol." Agronomía Costarricense, January 31, 2023. http://dx.doi.org/10.15517/rac.v47i1.53968.

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Introducción. Debido a la alta tasa de degradación del suelo a nivel mundial, se requiere encontrar prácticas agrícolas que promuevan la conservación de suelos. Objetivo. Evaluar el balanceo estático de cargas de un tractor dedicado a la labranza, por medio de diferentes distribuciones de contrapesos en sus ejes, para mejorar las propiedades físicas, mecánicas e hidráulicas y la eficiencia de operación en un suelo vertisol. Materiales y métodos. Se plantearon 3 balanceos de cargas diferentes en los ejes delantero y trasero 40-60%, 30-70% y 50-50%; mediante la adición de contrapesos en el eje trasero del tractor. Se realizaron muestreos de campo a una profundidad de 15 cm en 3 etapas de muestreo (antes de mecanizar, inmediatamente y 2 meses después de mecanizar) en un vertisol con cultivo de pasto (Digitaria decumbens Stent). Se analizaron las variables de contenido de humedad del suelo, densidad aparente, límites plásticos, resistencia a la penetración del suelo, así como las necesidades hídricas del cultivo de acuerdo con los tratamientos. Además, se determinaron variables de operación y eficiencia, tales como profundidad de labranza, patinaje, consumo de combustible y fricción. Se analizaron las diferencias de las variables entre los tratamientos y entre etapas de muestreo con el fin de determinar el tratamiento con la menor afectación a las propiedades del suelo y mayor eficiencia de operación. Resultados. Se encontraron diferencias significativas entre los balanceos de carga por eje evaluados para todas las propiedades del suelo analizadas, excepto en el contenido de humedad. El balanceo 30-70% presentó los valores más bajos de consumo de combustible y de agua para el riego, patinaje, resistencia al corte y resistencia a la penetración. Conclusiones. El balanceo 30-70% se considera ideal para mecanizar bajo las condiciones estudiadas. No se recomienda mecanizar con el balanceo 50-50%, ya que la profundidad de labranza y los cambios en las propiedades del suelo fueron en detrimento de algunas propiedades del mismo.
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