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1.
Summary
Considering leguminous trees Leucaenaand Gliricidiaas good sources of quality food, on-station and on-farm studies were conducted in the humid zone of West Africa to establish
animal responses to levels, times and forms of browse supplementation, to develop alternative feeding strategies for utilising
limited feed supply and to assess the economic benefits of feed supplements as against the use of tree foliage as mulch for
crop production. Results indicate that at any level of supplement, sheep grew twice as fast as goats. The main benefits of
supplementation came through increased growth and survival. Form and level of supplementation had significant effect on intake.
Economic analyses showed that crop response to mulching was the principal competing determinant of whether the use of tree
foliage as feed supplement was economic.
Beneficios Nutricionales Y Economicos De La Utilizacion DeLeucaena YGliricidia Como Suplementos Para Pequenos Rumiantes En Zonas Humedas Del Africa Occidental
Resumen Considerando que los árboles de los génerosLeucaena y Gliricidia son fuentes de alimento de buena calidad, se llevaron a cabo estudios en granjas y estaciones experimentales en zonas húmedas del Africa Occidental para determinar (1) la respuesta de los animales a diferentes niveles, momentos y formas de suplementación, (2) desarrollar estrategias de alimentación alternativas para aprovechar alimentos escasos y (3) determinar los beneficios económicos de la utilización de las hojas de los árboles mencionados como suplemento en lugar de como sistema de protección de los cultivos. Los resultados indicaron que, para cualquier nivel de suplementación, las ovejas crecieron dos veces más deprisa que las cabras. Los principales beneficios de la suplementación fueron un aumento en el crecimiento y en la supervivencia. La forma y el nivel de suplementación tuvieron efectos significativos sobre la ingestión. Los análisis económicos indicaron que la respuesta de los cultivos a la protección con hojas y estiercol fue el pricipal factor a tener en cuenta a la hora de decidir acerca de si la utilización de las hojas como suplemento para el ganado resultaba económica.
Interets Economiques Et Nutritionnels DeLeucaena EtGliricidia En Tant Qu’Apports Alimentaires Pour Les Petits Ruminants De L’Afrique Humide De l’Ouest
Résumé Considerées comme des sources nutritionnelles de qualité, des études furent menées surLeucaena etGliricidia dans les fermes et les lieux d’élevage dans la zone humide d’Afrique de l’ouest dans le but d’établir les résponses des animaux aux niveaux, durées et formes du broutage, pour développer des stratégies alternatives d’alimentation pour l’utilisation limitée d’apports alimentaires et pour estimer les avantages économiques des suppléments nutritionnels par opposition à l’utilisation de ces legumineuses comme terreau pour la production de récolte. Les resultats montrent que quel que soit le niveau d’apport nutritionnel, la croissance des moutons fut deux fois plus rapide que celle des chèvres. Les principaux intérêts de l’apport nutritionnel résiderent dans l’augmentation de croissance et de la survie des animaux. La nature et le niveau de l’apporteurent un effet significatif sur la consommation. Des analyses économiques montrérent que la résponse des récoltes après apport en terreau fut le principal facteur en compétition d’un point de vue économique, pour l’utilisation de ces légumineuses comme supplément alimentaire.相似文献
2.
Crop and livestock production in the Guinea savanna zone of northern Ghana has been declining over the past years as a result
of increasing pressure on land. To sustain soil productivity, pigeon pea(Cajanus cajan), a leguminous perennial crop was evaluated for its potential as a short duration fallow crop for fodder and grain, and maize
(Zea mays)production. It involved comparing a natural fallow (i.e., control) and four improved fallows of pigeon pea pruned annually
at 30 cm, 60 cm and 90 cm from the ground, and unpruned pigeon pea over a two-year period. After this time, the land was cleared
manually and planted to maize. The highest mean annual biomass of pigeon pea over the two-year period of 6.1 t ha−1 dry matter (DM) was obtained by pruning at 60 cm. The highest leaf litter production and pigeon pea seed yield was obtained
from the no pruning treatment. The mean maize grain yield from the improved fallow (3.02 t ha−1) in the first year after clearing was significantly (P < 0.05) greater than that of the natural fallow (1.54 t ha−1). Considering the biomass of pigeon pea from pruning, pigeon pea seed yield and maize grain yield after the pigeon pea, pruning
pigeon pea at 60 cm is the most promising regime for crop-livestock production systems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
3.
Adriana Vella Sinéad Murphy Joan Giménez Renaud de Stephanis Barbara Mussi Joseph G. Vella Kamel Larbi Doukara Daniela Silvia Pace 《水产资源保护:海洋与淡水生态系统》2021,31(Z1):110-136
- Preservation of endangered species is now recognized as a relevant component of regional and global conservation actions achieved through the maintenance of the remaining populations in a favourable conservation status. The Mediterranean common dolphin (Delphinus delphis) is listed as an Endangered subpopulation in the International Union for Conservation of Nature Red List, with declining numbers in some of the areas where it has been studied for numerous years. Prey depletion, fisheries bycatch, pollution, health risks, and climate change are among the recognized threats that the species is facing in the region.
- The existing national, regional, and international legislation pertinent to Mediterranean countries should aid greater science–policy–management integration and support innovative research and monitoring towards effective conservation. The challenges inherent in studying the pelagic D. delphis should not preclude the use of long-term, year-round, multiplatform surveys, side by side with the latest molecular tools, which aid our understanding of its populations' genetic diversity, resistance to diseases, and resilience in a semi-enclosed fast-changing sea.
- Addressing the multiplicity of problems confronting the species requires collaborative effort at all levels to share and merge resources, data, and expertise more efficiently. In this review, we provide an overview of the current knowledge on the Mediterranean common dolphin, the main threats, and knowledge gaps that are priorities for addressing its conservation, while providing clear recommendations for effectively safeguarding the species and its habitat at both local and regional levels.
4.
Two experiments evaluated variations in feed value among Calliandra calothyrsus provenances. In Experiment 1, edible forage
production of four provenances were evaluated at Ibadan, southwestern Nigeria over a 2-year period in three seasons: main-wet
(April–August), minor-wet (September–November) and dry (December–March). Forage samples from the main-wet and dry seasons
were incubated for 6, 12, 48, 72 and 96 h in rumen-fistulated steers to estimate in sacco dry matter (DM) and nitrogen (N)
degradation characteristics. In vitro gas production was estimated over 3, 6, 12, 24, 48, 72 and 96 h of incubation. In Experiment
2, DM degradation characteristics of 14 provenances of C. calothyrsus planted on an acid soil in Yaounde, Cameroon, were evaluated.
Data were subjected to cluster analysis for grouping, and the 14 provenances were placed into four distinct cluster groups.
Based on the potential extent of DM and, N degradation and gas production characteristics in Experiment 1, the four provenances
of C. calothyrsus were classified into three forage quality groups: high (ILCA 16310), medium (ILCA 14891, ILCA 15166) and
low (NFTA 896). In Experiment 2, using the extent of DM degradation as a forage quality index, C. calothyrsus provenances
in clusters 3 and 4 (namely: 51/92, 11/91, 13/91, 45/92, 10/91, 15/91, 18/91, 134/91, 12/91, 62/92), were relatively higher
in quality than their counterparts in clusters 1 and 2. The results suggested the existence of intra-species variation among
the provenances, and confirmed earlier observations that forage quality of C. calothyrsus could be improved through provenance
evaluation.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
W. O. Larbi 《Land Degradation \u0026amp; Development》2003,14(5):513-514
6.
Dalila Souguir Howaida Ibrahim Abd-Alla Ezzedine El Ferjani Mohamed Larbi Khouja Mohamed Hachicha 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(8):688-696
Salt stress is more and more becoming a serious problem in the world especially if we consider its damaging effect on the plant growth and yield. The cultivation of medicinal plants, such as Aloe vera, might be an alternative for the saline water use and salt-affected soils occupation. Aloe vera, commonly known as aloe, is one of the primary medicinal plants with multipurpose applications going from pharmaceutical to cosmetic aspects with a promising economic return. Aloe plants were cultivated and irrigated, for 14 months, with drinking water (C0) and with two levels of salt (C1 and C2). Changes in growth, hydrogen peroxide (H2O2), lipid peroxidation and phenolic compounds were examined in leaves at harvest. Depressive effects of salt irrigation on the plant growth parameters and a perturbation in inorganic ion contents were found especially with a high level of salt in the irrigation water. The intracellular oxidative stress was evaluated with the H2O2 production. Our results showed that the H2O2 content increased with the accumulation of the toxic ion (Na) in the leaf tissues. In addition, lipid peroxidation, measured by the malondialdehyde (MDA) level, increased as well with salt augmentation in the irrigation water. In response to salt stress, Aloe leaves showed a significant increase in the levels of phenolic compounds too. These results suggest that Aloe can be planted in soils affected by salinity and irrigated with salt water at least at a moderate concentration used in the present study. 相似文献
7.
A. Larbi A. A. Awojide I. O. Adekunle D. O. Ladipo J. A. Akinlade 《Agroforestry Systems》2000,48(2):157-168
Seasonal fodder production responses of five shrubs (Centrosema arenarium, Desmodium strigillosum, Desmodium velutinum, Phyllodium pulchellum, and Tadehagi triquetrum)and five trees (Albizia gummifera, Berlinia grandiflora, Albizia niopoides, Bauhinia monandra, and Inga edulis) to pruning heights ranging from 15 to 75 cm were evaluated during the main-wet, minor-wet, and dry seasons of 1993 and 1994 in the forest-savanna transition zone of West Africa. Fodder from the main-wet season was analysed for nitrogen (N) and phosphorus (P), and dry matter degradation characteristics after 6, 12, 24, 48, 72 and 96 h of incubation in rumen-fistulated N'Dama steers. In the minor-wet season, fodder production of all species increased in response to increasing pruning height with the exception of P. pulchellum and A. gummifera. Highest fodder production was attained at a pruning height of 45 cm for the Desmodium species, 50 cm for P. pulchellum, and 75 cm for the rest of the species. Concentrations of N and P varied significantly among the species; for N the ranges were 28.7–38.8 g kg–1 (shrubs) and 25.3–44.5 g kg–1 (trees), while for P the ranges were 3.26–7.04 g mg–1 (shrubs) and 3.58–6.76 g mg–1 (trees). Dry matter degradation characteristics differed significantly among shrubs and trees; ranges for shrubs were: soluble fraction (a), 128–185; degradable fraction (b), 664–703; potential degradability (PD), 793–857, as g kg–1; rate of degradation (c), 0.0241–0.0308 as % h–1 while for trees ranges were: (a), 139–160; (b), 651–826; (PD), 824–970, as g kg–1; (c), 0.0143–0.0227 as % h–1. Based on fodder production and quality, C. arenarium, D. strigillosum, D. velutinum, B. monandra, I. edulis, and A. niopoides were the most promising species for the development of animal agroforestry technologies in the west African forest-savanna transition zone and similar environments in the tropics.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
8.
The study investigated rumen dry matter (DM) degradability characteristics in a completely randomized design and the effects of milk, sweet potato foliage (SPF) from three cultivars (A = TIS-87/0087; B = TIS-8164; C = TIS-2532.OP.1.13), dried brewers' grains (DBG) and cottonseed meal (CSM) as supplements to Panicum maximum (Panicum) for pre-weaned calves in randomized complete block designs. Diet 1 = milk + SPF-A foliage + Panicum, Diet 2 = milk + SPF-B foliage + Panicum, Diet 3 = milk + SPF-C foliage + Panicum, and Diet 4 = milk + DBG & CSM + Panicum (as control). Dry matter (130 ± 0.4 to 864 ± 3.9 g kg− 1), ash (54 ± 4.2 to 173 ± 2.8 g kg− 1 DM), OM (827 ± 4.2 to 946 ± 5.7 g kg− 1 DM), N (7.4 ± 0.6 to 38.6 ± 1.4 g kg− 1 DM), and NDF (439 ± 1.4 to 774 ± 8.5 g kg− 1 DM) contents were highly significant (P < 0.01). In Trial I, 16 pre-weaned calves were used over 70 d with milk intake (34.8 ± 4.4 ml kg W− 0.75 d− 1), Panicum DMI (22.3 ± 2.77 g kg W− 0.75 d− 1), total DMI (35.7 ± 2.83 g kg W− 0.75 d− 1), and LWG (198 ± 44.6 g d− 1) not significantly different (P > 0.05). Supplement DMI varied (P < 0.05) from 11.6 g kg W− 0.75 d− 1 in Diet 3 to 16.6 g kg W− 0.75 d− 1 in Diet 4. In Trial II, 16 pre-weaned local and crossbred calves were involved over 77 d with initial age of calves, Panicum intake, metabolic DMI, and LWG similar (P > 0.05) among crosses. Birthweight varied (P < 0.05) from 17.3 kg for N'Dama × Jersey crosses to 21.2 kg for White Fulani × Brown Swiss crosses. Supplement and total DMI ranged (P < 0.05) from 172 to 483 g d− 1 for N'Dama × Jersey crosses to 233 and 674 g d− 1 for non-inseminate or purebred calves, respectively. The LWG in the White Fulani × Brown Swiss and the N'Dama × Jersey calves were respectively 30% and 24% better, though not significantly, than purebred calves. In Trial III, rumen DM degradability characteristics of feeds in three N'Dama steers showed no significant differences (P > 0.05) in slowly degradable fraction (b) and rate of degradation of b (c). Soluble fraction (a), 48-h degradation, potential degradability (PD) and effective degradability (ED) varied significantly (P < 0.05) and were lowest in Panicum, but similar for foliage among the three sweet potato cultivars. Panicum fodder showed improvements in degradation characteristics with supplementation. 相似文献
9.
A. Larbi J. W. Smith I. O. Kurdi I. O. Adekunle A. M. Raji D. O. Ladipo 《Agroforestry Systems》1996,33(1):41-50
Millettia thonningii (Schum. & Thonn.) Bak., a nitrogen fixing shrub native to Africa and Albizia lebbeck Benth, were harvested at 0.50 m above ground level after one year of establishment to determine edible forage production. Harvests were made at the end of the main (April–August) and minor (September–November) wet, and dry (December–March) seasons for two years. Dry season edible forage samples were analyzed for concentrations of crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (NDF), acid detergent lignin (ADL), cellulose (CL), soluble phenolics (SOPH) and proanthocyanidins (PAs). In sacco dry matter (DM) and nitrogen (N) degradation and in vitro gas production (GP) characteristics were also determined on dry season edible forage samples. Edible forage production of M. thonningii was significantly lower than A. lebbeck during the wet seasons. Millettia thonningii had relatively lower CP and PAs, but higher NDF, ADF, ADL, CL and SOPH than A. lebbeck. In sacco DM and N degradation and in vitro GP parameters of M. thonningii were significantly lower than A. lebbeck. Parameters of in sacco DM degradation and in vitro GP were highly correlated. Millettia thonningii appeared to be of lower feed value than A. lebbeck based on edible forage production, chemical composition, in sacco DM and N degradation and in vitro GP characteristics. 相似文献
10.
Mhemmed Gandour Mohamed Larbi Khouja Lamjed Toumi Saîda Triki 《Annals of Forest Science》2007,64(5):549-555
Twenty-six provenances (2 340 plants) of cork oak (Quercus suber spp.) originating from Portugal, Spain, Italy, Morocco, Algeria, and Tunisia were tested for genetic variation among and within provenances by growth traits. Seven morphometrical characters were measured in 90 plants from each provenance. Analysis of variance showed highly significant differences for all characters. The phenotypic coefficient of differentiation reached 0.24 for the form and 0.22 for height, thus revealing a strong structuring between the provenances. Comparative study of growth among the provenances revealed more vigorous growth and better survival rate for those from Morocco, Spain, and Portugal, which may constitute better materials for afforestation. Furthermore, this variability appeared to be geographically structured and would be mainly genetically controlled, as cork oak provenances were cultivated under the same environmental conditions. Our results should be helpful for guide forest managers in afforestation. 相似文献