The role of crop residues as livestock feed resources in semi-arid areas of Adami Aulu district, Ethiopia

Abstract

The study was conducted in Adami-tulu district of Ethiopia, using structured questionnaire, to investigate the extent of crop residue production, utilization and socio-economic limitations facing their utilization for livestock feeding. Chemical composition, intake and digestibility studies were also undertaken for three crop residues, namely, maize stover, teff straw and haricot bean haulms that are abundantly produced in the area. The results indicated that a significant amount of crop residue is annually generated from the production of maize, haricot bean, teff, wheat, sorghum and barley, all of which are used, though to a variable extent, for livestock feeding. Alternative uses of the crop residues and their leftovers include construction, firewood, fertilizer and sale. Although crop residues are badly required, both for livestock feeding and for other purposes, there is unavoidable wastage as a result of inability to collect them mainly because of lack of transportation, labour and associated financial constraints. Other contributing factors to crop residue wastage include storage problems, improper mode of utilization (e.g. in situ for maize and sorghum stovers) and lack of know-how as to the feeding value of some residues such as haricot bean haulms. Chemical analyses of the three by-products studied indicated that the by-products have low nitrogen content ranging from 3.6 to 5.5% and are composed of cell wall components with little soluble cell contents. Despite such indications of the poor nutritional quality of the crop residues, none of the sampled households were found to use any improvement strategies such as physical or chemical treatment and concentrate or legume supplementation. The major bottlenecks for such practices were shortage of labour, finance, and lack of know-how about and accessibility to the methods. The voluntary dry matter intakes by bulls fed on maize stover, teff straw and haricot bean haulms were 2.9, 4.3 and 3.9 kg DMiday, or 1.4, 2.0 and 1.8 kg/lOO kg live weight, respectively. Generally, the intake values of maize stover were significantly lower (P<0.05) than that of the other two by-products. Crude protein intake was the highest for animals fed teff straw. There was no relationship between live weight of animals and the type of residues consumed. Digestibility study indicated that maize stover was more digestible than the other two residues. The apparent DM digestibility coefficients were 54.5, 50.5 and 53.0% and that of OM were 59.1, 54.4 and 55.0% for maize stover, teff straw and haricot bean haulms, respectively. Generally, it is concluded that although large amounts of crop residues are produced and are mainly used for livestock feeding, their full and efficient utilization for livestock feeding has been hindered by economic problems and inadequate know-how of the farmers as to the handling and processing of the residues. Training farmers in the best methods of collection, storage and treatment of their crop residues, and in the principles of supplementation are suggested as vital measures that may lead to efficient utilization of these low quality but readily available feed resources. For this to be effective, the role of of government in terms improving the financial capabilities of farmers and their access to improved technologies related to crop residue feeding is of paramount importance.