The root of the medicinal plant Halothamnus somalensis traditionally used to treat endo-parasites of animals and humans was evaluated against endo-parasites in naturally infected goats. The goats were drenched with a crude preparation of the plant at two different doses (0.5 and 2 g/kg live weight [LW]). The dose of 2g/kg LW reduced faecal egg count (EPG) by 50%. Packed cell volume (PCV) was also significantly higher for goats that received 2 g/kg LW. The reduction in faecal EPG and increase in PCV values were negatively correlated. There was no effect on LW change but body condition score was higher for goats that received treatment than goats in the control group. Future research should focus on evaluation of different extracts from different parts of the plant using laboratory animals and small ruminants.

Pasture research led by the International Center for Tropical Agriculture (CIAT) and national institutions during the 80's and 90's, contributed with new Brachiaria species with various characteristics and uses that were incorporated with success in livestock production systems in the lowlands of Latin America. Brachiaria brizantha, Brachiaria dictyoneura, Brachiaria humidicola and Brachiaria ruziziensis are some of the forage materials released by research institutions in the region. Despite its indisputable advantages, the Brachiaria genus presents limitations because of its low tolerance to prolonged droughts and its high susceptibility to spittlebug, a pest that causes considerable economic losses to the livestock industry. Thus, most recent research in CIAT's Brachiaria breeding program has focused on the development of a second generation of Brachiaria grasses: outstanding agronomic characteristics, establishment vigor, good sprout capacity, high biomass production and nutritional quality, good seed production, resistant to Rhizotocnia and to multiple spittlebug species. The results of this effort have conveyed to the recent release of Mulato grass, the first hybrid of the Brachiaria genus obtained by CIAT's genetic improvement program. In the waiting list of the second generation of Brachiaria grasses is hybrid #4624 (CIAT 36087), to be released in 2005, having a similar forage quality as Mulato and with all the attributes defined for the second generation of Brachiaria grasses. Moreover, several other hybrids are in advanced stages of evaluation and close to being released as commercial cultivars. The potential economic impact of the adoption of new Brachiaria hybrids on livestock production systems was evaluated using the Economic Model MODEXC. Two regions were considered in Colombia: the Northern Coast and the Eastern Plains. In Mexico, the tropical region; and in Central America, its six constituent countries. The model estimates the economic benefits attributable to the utilization of the new materials, disaggregating per country, region, ecosystem, production system and large social groups (consumers and producers). It works with two types of parameters: the technical ones that characterize the new technology and its process of dissemination, and the economic ones representing the conditions of market supply and demand of both beef and milk affected by the technical change. The benefits of the new technology (from the year 2007) were calculated for a period of 20 years and the results were expressed in terms of the net present value (NPV) and annuities. The estimates were made using alternatively an economic framework of open and closed economy. In a closed economy, without international trade, the NPV of the technological benefits was estimated at US$4,166 million, of which 54% would be generated by the marketing of beef and the rest by milk. Most of the benefits were concentrated in Mexico, US$2,831 (68%); followed by Colombia, US$960 million (23%), and Central America, US$363 million (9%). In order to have criteria on the extent of the estimated technological benefits, the value of beef and milk yield during 2003 was calculated in the reference countries. The NPV is equivalent to 44% of the value of that year, ranging between 16% in Honduras and 78% in Nicaragua. The results show the importance of the dual purpose livestock production system. In most countries, more than half of the technological benefits was generated in this system: Colombia 70%, Central America 62%, and Mexico 50%. When a country is self-sufficient and the surplus resulting from the technical improvements is marketed domestically, the benefits are transferred to consumers who are favored with the reduction in prices, making possible for them to increase consumption. In the case of a closed economy, consumers would capture 83% of total benefits. Trade liberalization implies a re-distributive process favoring producers. Export purchases increase total demand and restrain the fall of domestic prices. In an open-market economy, the share of benefits to producers would rise to 46%. Research investment is conceived as a primary mechanism to achieve two of the most basic social goals: 1) poverty reduction and improvement in equity, and 2) the promotion of economic growth. Having this premise, in order to establish to what extent this technical change contributes to the fulfillment of these goals, the acquired benefits were estimated for the most vulnerable population groups: a) The two quintiles of poor consumers, representing 40% of total population, and b) the small producers. In both schemes, open or closed economy, both groups receive more than one-fourth of the benefits from technical change, 27% and 31%, respectively. This is equivalent to a NPV ranging between US$1,137 to 1,303 millions. Because the hybrids require better soils or fertilizer inputs to maintain forage biomass productivity and quality, the study was made with conservative hypotheses about changes in productivity and the size of the area to be planted. Despite the definition of the levels of critical variables, especially those associated with the productivity and the adoption of the new Brachiaria hybrids, conservative criteria were considered in order to avoid overestimating the benefits; it is important to evaluate the sensitivity of these, against undesirable changes of those variables. For this purpose, three alternative scenarios were established: 1) The reduction of 50% of the area cultivated with new Brachiaria hybrids, 2) the reduction of 10% in the yields of the new materials, and 3) the increase of 50% in the total time of adoption. The most critical variable in the determination of the amount of benefits is yield (productivity) of the new technology, in terms of beef and milk per hectare. The elasticity of the benefits regarding the yields was estimated at 2.2 for Colombia and 1.8 for Central America and Mexico. This suggests that if the yield declines by 1%, the reduction of the social benefits is more than proportional. The social benefits are less elastic with regard to the area planted with new Brachiaria hybrids or the time of adoption. For example, in Colombia, if the area with improved materials declines by one percentage point, the benefits will diminish at approximately six tenths of one point. In all the proposed alternative scenarios, the investment in the development of these new pastures are economically attractive, despite the adverse circumstances proposed in these scenarios. The technological benefits expressed as an annuity (a fixed annual payment received for a specific number of years) shows that the investment for the development of new forage options is very low, less than US$ 20 million, compared with the annual benefits resulting from the use of these new materials.

Smallholder poultry as a tool for poverty alleviation has been developed and widely applied in Bangladesh. In this paper, the evolution of the model has been summarized and studies conducted to assess the impact of the poultry model at various stages of its evolution have been critically reviewed. The results indicate that the project has reached the poor though not always ultra poor, the main target of the model, and that participants have benefited positively in terms of income, consumption and nutrition, empowerment of women. However, the results need to be assessed with a high degree of caution because of several methodological limitations of the impact studies. These limitations have been illustrated and suggestions have made for more objective assessment of impact of past projects and for conducting additional research for supporting smallholder poultry as a tool for poverty alleviation.

In the study area predominantly three marketing options were available for the dairy farmers; unorganized vendors, formal / organized dairy cooperatives and integrated contract system. A majority of dairy farmers around 57.3 percent had shifted from one marketing option to another. The rest 42.7 per cent of dairy farmers remained in the same marketing option from the day they began commercial milk production. A major shift from vendors (informal system) to contract (39.5 per cent), followed by vendor to co-operative (24.4 per cent) and co-operative to vendor (19.8 per cent) was noticed. Irregularity in payment and stoppage of procurement by vendor system made dairy farmers shift from vendor system to others. After the weakening of vendor- farmer relationship and initiation of Milk Producer Cooperatives at the village level, there has been a shift from vendor to co-operative system. When the dairy sector opened for private investment coupled with poor performance of cooperatives, farmers shifted towards new marketing option the 'integrated contract system'. Irregularity in payment, distant location of collection centre and inability to milk the animals were reasons for shifting back to vendor from other marketing options. Prompt payments, sustainability of marketing systems in business were major factors responsible for retaining members and attracting new dairy farmers. Dairy farmers with the experiences of various marketing options gave more value to the prompt payment for the milk sold on comparing to milk prices.

The objective of this study was to assess the carcass characteristics of two goat breed types under different durations of feedlot management. Forty eight yearling intact male Borana (n=24) and Arsi-Bale (n=24) goats were used in a 2 x 3 factorial arrangement, the factors being breed-type (Borana and Arsi-bale) and feeding days (90, 120 and 150). The goats were slaughtered after 18 hours fasting to evaluate the various carcass traits. The carcasses were separated into leg, lion, rack, shoulder and neck and breast and shank primal cuts. The Borana goats possessed heavier live weight, empty body weight, carcass weight and length than the Arsi-Bale goats in the feedlot environment. Dressing percentage varied from 41.0 to 45.9% for both goat breed types. Borana had greater rib eye area than Arsi-Bale goats for 120 (42.9±3.99) and 150 (47.3±1.28) feeding days. Back fat thickness was higher for both breed-types for 150 days feedlot feeding. The highest bone proportion was 30.9% for Arsi-Bale goats while the lowest was 25.7% for Borana goats. The percentage of rack fat of Borana was higher than for the Arsi-Bale goats.

The objective of this study was to understand the perception of agricultural producers in Colombia who currently do not own livestock about the role of cattle in alleviating poverty in their farms. Data came from direct survey interviews in 2002 with 143 farmers who did not own cattle in the five most important regions of animal production in Colombia to elicit their perception about the role of livestock as a pathway out of poverty. Selected regions were: Piedmont, Caribbean, the Coffee-growing region, the highlands of Antioquia, and the Cundiboyacense altiplanicie. Most smallholders interviewed in the Piedmont had cattle in the past (85%), followed by producers in Antioquia (60%) and least in the Coffee-growing region (39%). The most important reason for selling their cattle in all regions was due to financial crisis and needed cash (ie., from 27% of smallholders interviewed in the Caribbean and the Cundiboyacense altiplanicie to almost 50% in the Piedmont). Most smallholders surveyed used the money from the sale of animals to pay health bills of family members, to pay off debts, and/or to use the cash to survive due to crop failure from extreme weather conditions (ie., drought or frost damage). The most striking result is that 76% of farmers in Antioquia to 97% of smallholders in the Cundiboyacense altiplanicie would like to own cattle if they had the opportunity. The most important reason for owning cattle in all regions was as a mechanism for savings and building capital. The second most important reason in all regions was to obtain milk and beef for family consumption, except in Antioquia where this issue was irrelevant. Other reasons for owning cattle were to reduce and diversify risk due to crop failure and to utilize manure as fertilizer. The preferred animal category to own in all regions was by far the milking cow, ranging from 52% of smallholders in Antioquia to 96% in the Cundiboyacense altiplanicie. Results from this study show that cattle are perceived by small-holder farmers as a contribution to the improvement in the quality of life. The challenge is to develop novel mechanisms to provide smallholders with livestock, either through credit loans or thru the Fondos Ganaderos of Colombia, whose objective is to help small farmers who have production capacity but lack the resources to buy cattle.

Pasture research led by the International Center for Tropical Agriculture (CIAT) and national institutions during the 80's and 90's, contributed with new Brachiaria species with various characteristics and uses that were incorporated with success in livestock production systems in the lowlands of Latin America. Brachiaria brizantha, Brachiaria dictyoneura, Brachiaria humidicola and Brachiaria ruziziensis are some of the forage materials released by research institutions in the region. Despite its indisputable advantages, the Brachiaria genus presents limitations because of its low tolerance to prolonged droughts and its high susceptibility to spittlebug, a pest that causes considerable economic losses to the livestock industry. Thus, most recent research in CIAT's Brachiaria breeding program has focused on the development of a second generation of Brachiaria grasses: outstanding agronomic characteristics, establishment vigor, good sprout capacity, high biomass production and nutritional quality, good seed production, resistant to Rhizotocnia and to multiple spittlebug species. The results of this effort have conveyed to the recent release of Mulato grass, the first hybrid of the Brachiaria genus obtained by CIAT's genetic improvement program. In the waiting list of the second generation of Brachiaria grasses is hybrid #4624 (CIAT 36087), to be released in 2005, having a similar forage quality as Mulato and with all the attributes defined for the second generation of Brachiaria grasses. Moreover, several other hybrids are in advanced stages of evaluation and close to being released as commercial cultivars. The potential economic impact of the adoption of new Brachiaria hybrids on livestock production systems was evaluated using the Economic Model MODEXC. Two regions were considered in Colombia: the Northern Coast and the Eastern Plains. In Mexico, the tropical region; and in Central America, its six constituent countries. The model estimates the economic benefits attributable to the utilization of the new materials, disaggregating per country, region, ecosystem, production system and large social groups (consumers and producers). It works with two types of parameters: the technical ones that characterize the new technology and its process of dissemination, and the economic ones representing the conditions of market supply and demand of both beef and milk affected by the technical change. The benefits of the new technology (from the year 2007) were calculated for a period of 20 years and the results were expressed in terms of the net present value (NPV) and annuities. The estimates were made using alternatively an economic framework of open and closed economy. In a closed economy, without international trade, the NPV of the technological benefits was estimated at US$4,166 million, of which 54% would be generated by the marketing of beef and the rest by milk. Most of the benefits were concentrated in Mexico, US$2,831 (68%); followed by Colombia, US$960 million (23%), and Central America, US$363 million (9%). In order to have criteria on the extent of the estimated technological benefits, the value of beef and milk yield during 2003 was calculated in the reference countries. The NPV is equivalent to 44% of the value of that year, ranging between 16% in Honduras and 78% in Nicaragua. The results show the importance of the dual purpose livestock production system. In most countries, more than half of the technological benefits was generated in this system: Colombia 70%, Central America 62%, and Mexico 50%. When a country is self-sufficient and the surplus resulting from the technical improvements is marketed domestically, the benefits are transferred to consumers who are favored with the reduction in prices, making possible for them to increase consumption. In the case of a closed economy, consumers would capture 83% of total benefits. Trade liberalization implies a re-distributive process favoring producers. Export purchases increase total demand and restrain the fall of domestic prices. In an open-market economy, the share of benefits to producers would rise to 46%. Research investment is conceived as a primary mechanism to achieve two of the most basic social goals: 1) poverty reduction and improvement in equity, and 2) the promotion of economic growth. Having this premise, in order to establish to what extent this technical change contributes to the fulfillment of these goals, the acquired benefits were estimated for the most vulnerable population groups: a) The two quintiles of poor consumers, representing 40% of total population, and b) the small producers. In both schemes, open or closed economy, both groups receive more than one-fourth of the benefits from technical change, 27% and 31%, respectively. This is equivalent to a NPV ranging between US$1,137 to 1,303 millions. Because the hybrids require better soils or fertilizer inputs to maintain forage biomass productivity and quality, the study was made with conservative hypotheses about changes in productivity and the size of the area to be planted. Despite the definition of the levels of critical variables, especially those associated with the productivity and the adoption of the new Brachiaria hybrids, conservative criteria were considered in order to avoid overestimating the benefits; it is important to evaluate the sensitivity of these, against undesirable changes of those variables. For this purpose, three alternative scenarios were established: 1) The reduction of 50% of the area cultivated with new Brachiaria hybrids, 2) the reduction of 10% in the yields of the new materials, and 3) the increase of 50% in the total time of adoption. The most critical variable in the determination of the amount of benefits is yield (productivity) of the new technology, in terms of beef and milk per hectare. The elasticity of the benefits regarding the yields was estimated at 2.2 for Colombia and 1.8 for Central America and Mexico. This suggests that if the yield declines by 1%, the reduction of the social benefits is more than proportional. The social benefits are less elastic with regard to the area planted with new Brachiaria hybrids or the time of adoption. For example, in Colombia, if the area with improved materials declines by one percentage point, the benefits will diminish at approximately six tenths of one point. In all the proposed alternative scenarios, the investment in the development of these new pastures are economically attractive, despite the adverse circumstances proposed in these scenarios. The technological benefits expressed as an annuity (a fixed annual payment received for a specific number of years) shows that the investment for the development of new forage options is very low, less than US$ 20 million, compared with the annual benefits resulting from the use of these new materials.

International audience | Au Sénégal, l'apparition des petites unités laitières semble être un facteur important dans le développement d'un système local amélioré de production laitière. Pour aborder cette réflexion, un aperçu a été conduit en 2002 à Kolda, au sud du Sénégal. L'approche "filière" a été choisie pour évaluer les transferts physiques, les niveaux des prix, la gestion de la qualité et l'organisation économique du secteur. Les résultats prouvent que les quantités de lait récoltées par les petites unités de traitement se sont accrues de 21 250 litres en 1996 à 113 600 litres en 2001. Avec la concurrence du lait en poudre importé, le futur développement du système dépendra certainement de l'amélioration des niveaux de productivité mais également de la satisfaction des besoins du consommateur en termes de qualité et de prix. Plus d'attention devrait être prêtée à la qualité spécifique des produits locaux.

Theoretical and experimental investigations are carried out to estimating the impact of the plough body working width on its specific draft resistance, as well as the ploughing efficiency. By using analytical correlations derived as a result of theoretical research, a computer algorithm has been worked out for simulating the functions of the plough body and the forces exerted by soil upon the operating parts, as well as its draft resistance. Specific draft resistance of the plough body, energy consumption, as well as labour efficiency and ploughing costs depend considerably on the working width of the body. By increasing it, the energy capacity, specific fuel consumption and expenditure decrease, but labour efficiency increases.

One of the prior trends of research is the problem studies of power economy of technological processes and quality automatic control. Though the theory of grain drying process has been developed profoundly, still there are problems in its implementation. The developed analytical and simulation models of grain drying are difficult to implement into practice because they do not contain all the factors, which influence the real grain drying process or they cannot be solved. The developed models enable to assess only the essentiality of factors and/or the fundamental basics of the process. In order to ensure the effective and user-friendly grain drying process, it is indispensable to develop the control methodology using system modelling approach. The present paper deals with the system approach to heat and mass transfer problem and the testing of the basic hypothesis of the diffusion theory about the normal distribution of particles in the diffusive environment.