| Forage Development and Management in Communal Grazing System in Malaysia F.Y. Chin ABSTRACT
INTRODUCTION Grazing reserves are land officially allocated by various state governments for use by farmers to rear cattle, buffaloes and other ruminants. Altogether 581 grazing reserves covering a total of 38, 287 hectares have been reported earlier (Chin 1989; Chin 1994a) but currently the number has increased to 656 covering 47,006 hectares of land. However, not all of the grazing reserves are readily useful as some are of unsuitable grounds, terrain or are too thickly forested areas. The natural grassland areas are mainly dominated by native species and are a mixture of grasses, herbaceous and woody broadleaves. If the area is moist and low-lying the tendency for sedges to thrive. Although some of the indigenous plants may individually provide good forage, the overall vegetation is generally of low productivity and offers poor quality grazing. In Laos, for instance, estimated stocking rate on such grazing land is 0.33 animal unit per hectare even under improved management conditions (Norachek et al. 1993). These grassland areas are also usually heavily grazed and in Malaysia, overgrazing is a common problem leading to rapid degradation of the natural pastures. Severe depletion of soil nutrients is another common problem as there is no proper management. Thus there is a need to increase productivity of these grazing forages for livestock and one strategy is to develop and manage grounds to provide better quality improved pasture species on them. National program and overall strategy for increasing productivity
of communal grazing land through forage cultivation The organized grazing system is effected under the different strategies outlined for cooperative group farming, share farming, land allotment scheme, organised grazing ground, fodder distribution and government/farmers joint use scheme (Chin 1994a). The land allotment scheme is also known as the livestock colony scheme; for instance, the ‘dairy colony’ concept where farmers are allotted separate plots on a grazing reserve to carry out their dairy activities. There is also a privatization scheme where some grazing reserves are leased to entrepreneurial farmers/ livestock producers for livestock rearing based on open improved pasture. Other income generating activities are sometimes included in the development of grazing reserves. Developed areas can be turned into agro-tourism projects to make them more viable through additional income. Deer rearing, village-styled homes for farm stay, fishing, hiking and camping facilities are included to increase their agro-tourism value. This strategy is important in order to sustain the interest of farmers to properly manage their grazing area. The development of grazing reserves for increasing livestock production is again being reemphasised as an important strategy under the recently implemented Third National Agricultural Policy. Strategies for forage development and management on communal grazing land Forage Development Introduction of legumes had been suggested as the quickest and most practical approach to large-scale improvement of natural grassland areas (Moog 1989). The stylos (Stylosanthes guianensis, S. hamata and S. humilis) are widely used because of their tolerance to acidic and low phosphorus conditions in the soil. In terms of grass species, the more aggressive and hardy Brachiarias (Brachiaria decumbens, B. humidicola and B. ruziziensis) are favoured. Imperata cylindrica grassland can be improved by oversowing with B. decumbens (Eng and Basery, 1991; Kaligis, 1993). Setaria (anceps) sphacelata cv Kazungula and S. guianensis has also been observed as a useful combination for over sowing onto I. cylindrica grassland for its improvement (Chin, unpublished information). B. decumbens is the major grass species planted for grazing in Malaysia because it is aggressive and hardy, highly responsive to nitrogen (N) fertilization, able to withstand heavy and close grazing, drought resistant and easily managed (Chin 1989, Chin, 1994a). On Malaysian cattle farms, the Brachiarias (namely B. decumbens, B. humidicola and B. ruziziensis) are planted on almost 80 percent of the total 6,185 hectares of improved pasture land; 70 percent alone being B. decumbens. More than 95 percent of improved communal grazing lands are planted with the same grass species. However, where pasture is used for the grazing of sheep, cultivation of B. decumbens is usually avoided. This is because of possible intoxication of sheep reportedly caused by steroidal saponins in the forage (Salam et al. 1992). B. humidicola and Panicum maximum are planted instead. There is limited use of other aggressive grasses including S. (anceps) sphacelata cv Kazungula, Cynodon plectostachus and Digitaria setivalva which are also quite aggressive species but the availability of planting material is a limiting factor. The latter two grasses can only be cultivated by vegetative means and this restricts their use in large-scale forage development. Where there is good control over the grazing, as in some organized grazing schemes, less aggressive grasses such as Panicum maximum varieties may also be planted, either as pure or in mixed sward. Legumes such as Centrosema pubescens, Desmodium intortum, D. ovalifolium, S. guianensis and even Arachis pintoi can be mixed with a Panicum maximum variety. The S. guianensis variety, Stylo CIAT 184, is useful for introduction onto grazing reserves as it is aggressive, persistent and seeds can be produced locally. However, mixed swards are not common as the main thrust in the improved pasture introduction programme has always been towards cultivating aggressive stoloniferous grass species, which makes the incorporation of legumes difficult. Shrubs and trees traditionally play a role in supplementing the grazing of animals in many countries as browse or fodder. In Malaysia, the use of browse/fodder shrubs and trees is very limited. Erythrina, Erythrina variegata, Gliricidia maculata, Leucaena leucocephala, Sesbania grandiflora and Acacia spp. are leguminous species considered as shrubs and trees for producing browse/fodder to increase forage biomass and quality on grazing land. Indigenous non-leguminous forest species such as Carallia suffruticosa, Ficus spp. Sapium spp. and Streplus asper have also been found useful for this purpose (Mustaffa and Chin 1991, Tay and Chin 1991, Chin 1994b, Chin and Tay 1994). S. asper is reportedly found in many parts of mainland South East Asia. It is also a known useful browse in Thailand (Manidool 1992). Where the natural herbaceous species Asystasia intrusa occurs in shadier conditions and on moist areas of grazing land, it is best left to grow on the field for grazing as it produces very good quality and palatable forage is produced by it. This species has very good crude protein levels of 24 to 25 % of dry matter at 3 to 4 weeks of maturity and 21% even at 6 weeks of maturity (Chin unpublished information). Forage Management Nitrogen (N) is the single most critical element and urea is most commonly used in Malaysia for pasture and fodder production (Chin 1979, Chin and Idris 1997), 150 to 200 kg N/ha/year is recommended for maintaining pure swards of improved grass pasture in this country 200 kg N/ha/year in the form of 356 kg urea /ha/year had been used to increase quality of pure improved grass pasture under ranch conditions (Choo 1993). 100 kg N/ha/year was generally regarded as the optimum rate of fertilizer N application in the Philippines (Javier and Moog 1975; Sena et al. 1976; Antonio et al. 1977; all cited by Valenzuela and Diesta, 1993). While most grasses would respond to N application up to as high as 750kg/ha/year, regular amount of 60 to 90 kg N/ha/cut can optimize forage output on the local soils of Thailand (Tudsri and Sawasdipanit 1993). Topdressing with phosphatic and potash fertilizers is also necessary to replenish P and K levels in the soil. N is not critical in mixed swards, assuming it is fixed by rhizobia in the roots of the legume. Previous work has shown that legumes including C. pubescens, D. intortum, Macroptilum atropurpureum, Pueraria phaseoloides and S. guianensis in mixed swards contributed N ranging from 10 to 264 kg/ha/year through N-fixation (Milers 1949; Warmke et al. 1952; Moore 1960; Montemayor 1974; Guzman 1975); all cited by Valenzuela and Diesta 1993). Legumes should be able to fix in excess of 100 kg N/ha/year (Middleton, 1973; cited by Valenzuela and Diesta, 1993). In Malaysia, mixed swards will not be provided with N, but with annual topdressings of 40-50 kg P/ha and 50 to 100 kg K/ha (Chin 1994a). Liming is particularly necessary to promote better rhizobium growth and N-fixation in legumes and practical levels of it should be applied once in every two years. Grazing at the proper age of regrowth is extremely important to get the best out of improved pastures and to provide for proper regrowth. With the advent in cultivation of aggressive species, pure grass pastures should be grazed at younger age of maturity, ranging between 18 to 28 days, depending on the species, in order to obtain good quality palatable forage (Chin 1995; Chin and Idris 1997). Well-managed B. decumbens, under good climatic conditions, is even grazed as early as 17 days. It has been recommended that, on a practical level, maximum benefit in terms of protein nutrition comes from grazing or cutting grasses at early maturity of even less than 4 weeks (Chin 1982). There was a misconception that good grass swards should look luscious, thick and tall, as usually such swards will have lost much of their nutritive value due to advancing maturity. Grazing younger pastures of 17 to 19 days of maturity has been advocated in order to obtain better quality forages of at least 13% crude protein which help increase average daily milk production and save on concentrate supplementation cost (Choo 1993; Choo et al. 1993; Chin 1995; Chin and Idris 1997). Strip grazing of adequately fertilized B. ruziziensis, P. maximum and P. maximum var. trichoglume every 24 to 27 days during the rainy season provided forage of relatively high crude protein of 12 to 15%, and digestibility of 60 to 65% (Watkin and Sukpituksakul 1992; cited by Tudsri and Sawasdipanit 1993). Need for more organized communal grazing systems Impact from forage development and management in communal grazing
systems At a macro level, the economic contribution from the livestock industry is increased through this strategy of improving communal grazing grounds for the grazing of farmers’ animals. Profitability to farmers is enhanced as there is improved nutrition for their animals resulting in increased animal productivity and better animal performance. This in turn improves their level of income and elevates their social status in their community. Through proper developmental and management techniques, surface vegetation degradation, soil erosion as well as soil fertility reduction is avoided ensuring that the introduction of forages in communal grazing systems is an environmentally sustainable practice. CONCLUSION Forage development and management in communal grazing systems is feasible. It also needs more organised grazing schemes to be introduced in order to control the use of the land by farmers and their livestock. Pure grass sward is common and aggressive and hardy, persistent, N responsive and drought resistant grasses that can withstand heavy and close grazing pressure are usually cultivated, particularly Brachiaria decumbens. The cooperation and commitment of farmers towards forage management is vital for success. ACKNOWLEDGEMENT The author wishes to thank the Director General of Veterinary Services, Malaysia, for his permission to present and publish this paper.
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