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Introduction, Selection and Evaluation of Annual Sown Forage Legumes Under Continental Mediterranean Climate Conditions in Pakistan
Get PDFThe upland areas (\u3e 1000 m) of Baluchistan Province in Pakistan (Latitude 28-32° N) experience a continental semiarid Mediterranean climate with some irregular additions of summer monsoonal rainfall. The current farming systems rely on the production of small ruminants from degraded Artemesia and Chrysapogon sp. rangeland and subsistence cropping of wheat/fallow rotations (Icarda, 1988). Sheep and goat numbers in Baluchistan have increased since 1955 from approximately two to thirteen million head in 1986 (Icarda, 1988). This has resulted in severely overgrazed rangelands and periodic acute feed deficits. In response the Arid Zone Research Institute has initiated a program for the introduction and screening of new forage and range species into the local farming systems. The forage crop component of this program which is reported in this paper has the dual objectives of (a) intensifying and diversifying crop production and (b) producing animal feed for periods of critical shortage and thereby reducing the current severe overgrazing on natural rangelands. Annual sown forage legumes principally Vicia and Lathyrus spp. have been the initial candidates for introduction (Kemick, 1978). The acute severity of the winter season in upland Baluchistan requires species either to be very frost tolerant or to be of a sufficiently short maturity period to allow the growth cycle to be completed between February and mid-May when intense heat and drought stresses terminate rainfed crop growth
Palatability of the Main Fodder and Pasture Species Present in S.E. Spain: I. Woody Species (Trees and Shrubs)
Get PDFIn S.E. Spain, livestock is mostly fed with the subproducts from cultivation of cereals. As a result of the limited feed resources available and because of the growth restriction imposed by climate, several feeding gaps occur along the year : at the end of summer, during winter, and at the end of spring. In a search of new fodder resources to cover the mentioned feeding gaps, a first step was to compare the palatability of the main fodder species present in cultivated and range areas
Effects of Straw Cover and Seed Burial on Changes in Hard Seededness of Annual Medics
Get PDFSelf-regenerating annual legumes, including subterranean clover and medics (Medicago spp.) are important pasture species in the cereal-livestock production zone of southern Australia and other Mediterranean climatic zones of the world. The pattern of germination in the genus Medicago, in which only a small percentage of seed germinates at one time because of hard-seededness has many ecological advantages particularly for the successful dissemination and colonization of medics. When medic pastures are incorporated into rotation systems with field crops the hard-seededness trait enables the medic seed population in the soil to survive periods of one, two or possibly three or more years of cropping without seed reserves being replenished. Cereal straw residues have been shown to cause substantial reductions in the density of self-regenerating annual medics (Quigley and Carter, 1985). Vegetative ground cover over summer is known to influence the breakdown of hardseededness in annual legumes (Quinlivan and Millington, 1962; Burton, 1964) thus affecting the density of seedlings which regenerate in autumn. However, this relationship has not been researched in detail and quantitative data on the effects of shading by stubble on germination of seed is limited. The location of seed within the soil profile would affect diurnal temperature variation which controls the rate of change of seedcoat permeability. Effects of depth of burial of seed in soil have been examined by Burton (1964) and by Taylor (1984, 1985) with subterranean clover. In view of the marked differences in the patterns of seed softening for medics and subterranean clover the deficiency in our knowledge of distribution of medic seed in soil profiles and the relevance of this to breackdown of hard-seededness is most serious : however, some data has recently been obtained by Quigley et al. (1987). This paper presents detailed information on the harmful effects of thermal insulation, either by straw residues or cover by soil, on levels of hard-seededness in barrel medic (Medicago truncatula)
Variability of a Tropical Savannah and its Influence on Management Practices and Animal Weight Gains
Get PDFThe savannah of the Colombian and Venezuelan plains have been relatively well studied from a floristic point of view and several major plant communities are recognized (Blydenstein, 1967). Nevertheless, the potential contribution of these plant communities to ruminant production have not been studied, except for the largest of these associations, that of the welldrained high savannah. Paladines and Leal (1979) have shown that it has low carrying capacity and sustains low levels of animal production both per head and per animal, despite moderate levels of primary productivity. In effect, animal weight gains range from 70-90 kg head-1 and 18-40 kg ha-1, with stocking rates of 0.2-0.5 AU ha-1 (1 AU = 350 kg). The low animal gains are due to the low nutritive value of the savannah vegetation even when immature (Hoyos, 1987; Vera et al., this congress), while the low performance per unit area is further affected by the need to burn mature herbage every 12-18 months, which results in a reduced carrying capacity. Under these conditions it has been clearly demonstrated that few management practices, other than judicious use of fire, can increase ammal performance (Paladines and Leal, 1979). The potential role of the other plant communities has not been documented. Nevertheless, it is a popular belief among local graziers that the value of the savannah in general, and therefore its potential animal productivity, increases as the percentage of poorlydrained and seasonally-flooded savannahs increase in the landscape. The purpose of the research reported here was to make a preliminary assessment of the different plant communities, both in terms of primary productivity and animal weight gains, based on data collected during the course of a large replicated grazing systems experiment which covered over 2000 has of savannah. Indications of potential differences among plant communities would help in deciding whether further specific research would be required
Utilization des Savanes Naturelles par des Troupeaux Bovins Allaitants en Guadeloupe
Get PDFAux Antilles Frarn;aises, comme dans de nombreuses regions tropicales, les prairies naturelles et parcours occupent des surfaces importantes, principalement dans les zones seches. En Guadeloupe, ces paturages denommes « savanes » sont domines par la presence d\u27une graminee de valeur pastorale moyenne, le Dichanthium spp. Ils constituent la base des apports fourragers dans la plupart des exploitations orientees vers la production de viande bovine, basee sur des animaux de race locale Creole. Cependant le chargement est eleve et l\u27alimentation complementaire faible et irreguliere. La conduite de la reproduction est sommaire, avec des velages toute l\u27annee et aucune politique de sevrage effectif. Aussi Jes performances zootechniques restent faibles et fortement influencees par les variations saisonnieres de productivite des paturages. Les travaux de l\u27I.N.R.A. en Guadeloupe sur la conduite des troupeaux allaitants ont done pour objectif de caracteriser au plan zootechnique les potentialites des savanes et d\u27evaluer des techniques visant a ameliorer leur productivite (Xande, 1985 ; Naves et al., 1987)
Effect of Fertilization with N-P-K on Yield and Botanical Composition of a Natural Pasture in Southern Italy
Get PDFThe hilly dry environments of Southern Italy are characterized by native pastures greatly deteriored due to unfavourable and variable pedoclimatic conditions, mostly to the rainfall pattern during spring and summer. Also the irrational utilization and the uncorrect cultural techniques take part in very low yield of these large pasture areas. For these reasons the studies on rational utilization of pastures and on the various treatments are particularly interesting. Among these agronomic treatments, mineral fertilization plays a primary role due to the well-know marked influence on the amount seasonal distribution and quality of forage production: also the botanical composition, as well-known, is affected by meteoric pattern and nutrients supply
Production des Parcours Saheliens et Possibilities de Rehabilitation
Get PDFDepuis 1970, la periode de secheresse a entraine une contraction de la vegetation sahelienne des plateaux vers Jes fonds de bassins versants avec un appauvrissement floristique des parcours et surtout une reduction de la production fourragere regionale. Qu\u27en est-ii du bilan semencier et existe-t-il des interventions susceptibles d\u27inverser le processus
Preliminary Studies of Improvement and Utilization of Natural Grasslands of Jiangxi Province in China
Get PDFJiangxi Province is situated in Southeast China, belonging to the midsubtropical monsoon region. There exists a vast acreage of natural grasslands to be utilized because of man\u27s activities. In the areas where the artificial grasslands cannot be opened up for the present, some semi-artificial grasslands may be set up by additionally seeding the natural grasslands to fine forage grass in mode of banded shallow cultivation to speed up their improvement and utilization. This will be favourable to the development of the graminivorous livestock hursbandry in the whole province
The Chemical Composition and Cellulase Digestibility of Pressed Crops Obtained in the Process of Green Crop Fractionation
Get PDFAlthough green crop fractionation (GCF) has been shown to increase the yields of dry matter (DM) and protein per unit area of a small farm per unit time, this process has attracted very little interest in India despite over four decades of research (Joshi, 1983). This is because almost all work on GCF has been carried out with an intention to extract leaf protein (LP) for human consumption and no attempts have been made to utilise the other two products obtained in the process viz., the pressed crop (PC) and the whey which carry with them over 85 % of the DM present in the crop. The recovery of LP is not going to be economical, even in the village-scale process developed by our Group (Joshi et al., 1984), unless both PC and whey are utilized properly in ruminant feeding. The objective of the present work was to study the chemical composition and in vitro cellulase digestibility of the pulp and PC samples obtained after fractionation of 20 short-duration crops
Effect of Inoculation of Lactic Acid Bacteria on Silage Fermentation
Get PDFMany commercial preparations containing lactic acid bacteria are used by the farmers as a silage additive. The trials of inoculation for silage have been employed by many researchers since the beginning of this century. However, the definite conclusion of the value of inoculants for silage is not obtained yet. Most of these inoculants are based on mixed cultures of lactic acid bacterium. Beneficial effect of inoculated silage must be discussed in connection with water soluble carbohydrate (WSC) content or carbohydrate source addition. The present study was carried out in order to know whether the effect of inoculation of lactic bacteria on silage fermentation was recognized