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Extent and implications of incorrect offspring-sire relationships in pastoral production system in Kajiado District, Kenya
2008
Maichomo, M.W. | Gitau, G.K. | Gathuma, J.M. | Ndung'u, J.M. | Kosura, O. | Olivier, H.O.
The aim of this study was to evaluate accuracy of farmer's paternity identification which determines success of future breed selection and hence genetic gain. Paternity of 269 Orma/zebu and Sahiwal/zebu calves was evaluated using genetic markers and the likelihood based method. Results indicate that only 6.7% farmer alleged paternities were confirmed, 88% parent-offspring relationships were rejected and 18% parent-offspring relationships were undetermined. However, 82% of offsprings were assigned at least 80% confident paternities to one of the sampled candidate males. These results suggest that there is need to institute proper breeding program in the pastoral area if farmers are to benefit from their current efforts of breed improvement.
显示更多 [+] 显示较少 [-]Acceptability of selected common shrubs/tree leaves in Nigeria by West African Dwarf goats
2008
Ikhimioya, I.
Fodder production, dry season leaf retention, and concentrations of crude protein and in vitro dry matter (DM) digestibility in fodder of Desmanthus virgatus, Desmodium cinereum, Desmodium gyroides, and Cajanus cajan were compared under cutting on an acid soil in southern Ethiopia. Desmodium cinereum, D. distortum, D. discolor, and C. cajan retained a higher percentage of green more fodder than D. gyroides and Desmanthus virgatus. Crude protein concentration in fodder of all species during the dry season was above 130 g kg DM, indicating that these species could be used as protein banks to supplement native pastures and crop residues during the dry season. Based on fodder production, dry season leaf retention, and concentration of crude protein in fodder, D. cinereum, D. distortum, D. disolor, and C. cajan are recommended for further testing with animals.
显示更多 [+] 显示较少 [-]Non-genetic factors affecting early growth traits and survival in Horro sheep
2002
Abegaz, Solomon | Duguma, G. | Gelmesa, U. | Terefe, F. | Negussie, E. | Rege, J.E.O.
Factors affecting the early growth and survival of indigenous Ethiopian Horro sheep were identified and the influence of each was assessed, based on data collected from 1978 97 from 4031 lambs at Bako Research Centre, Ethiopia. Year of birth, sex, type of birth or rearing, and parity had significant (P < 0.01) effects on birth weight (BWT), weaning weight (WWT), and six month weight (6MWT). With the exception of parity, the same factors affected yearling weight (YWT). Male lambs were heavier by 0.14, 1.1, 1.9, and 4.2 kg than females in BWT, WWT, 6MWT, and YWT. Single born lambs were heavier by about 0.5 kg than multiple born lambs at birth. Lambs born from primiparous ewes were lighter by 0.2 0.3 kg than lambs born from multiparous ewes at birth. With the exception of effect of type of birth and ewe age on survival to 3 and 7 days of age, respectively, year of birth, ewe (dam) age, type of birth, and BWT had significant (P < 0.01) effect on survival from three days to one year of age. The survival of multiple-born lambs was 0.8, 3.7, 8.3, 12.2, and 12.496 lower than single-born lambs at the age of 3, 30, 90, 180, and 365 days, respectively. Lambs born from primiparous ewes had lower survival rates compared to those born from multiparous ewes. Survival was very low in lambs with low BWT and improved with increase in BWT. In general, there are indications that there exists a critical BWT (about 2.6 kg) below which the survival of lambs declines drastically.
显示更多 [+] 显示较少 [-]Studies on the growth performance of native chicken ecotypes and RIR chicken under improved management system in northwest Ethiopia
2006
Hassen, H. | Neser, F.W.C. | Dessie, Tadelle | Kock, A. de | Marle-Koster, E. van
A study was conducted to evaluate the growth performance of native and RIR chickens under intensive management condition for 22 weeks using a standard commercial ration. Seven native chicken populations were collected from representative administrative zones in northwest Ethiopia. The experimental layout was a Completely Randomized Design (CRD) with three replications. Data on feed consumption, body weight and related parameters were collected up to the age of 22 weeks. The mean total feed intake for the seven native chicken ecotypes and RIR chicken lines at the end of their growth phase were 13.80, 15.16, 13.44, 13.25, 13.81, 13.36, 14.11 and 12.83 kg for the native chicken types named as Tilili, Gellilia, Debre-Ellias, Mello-Hamusit, Gassay, Guangua, Mecha and RIR, respectively. There was no significant difference in feed consumption among the tested chicken ecotypes. However, a significant (p<0.05) difference was observed in average body weight and body weight gain between the different lines. The average body weights for Tilili , Gellilia, Debre-Ellias, Mello-Hamusit, Gassay, Guangua, Mecha and RIR were 1191, 1186, 1054, 1222, 1038, 1249, 1257 and 1394 g respectively. The lowest and highest mean mature body weight at the age of 22 weeks were 1038 g for Gassay and 1257g for Mecha native chicken lines, respectively. Besides, the average mature body weight for Tilili, Gellilia, Debre-Ellias, Mello-Hamusit, Gassay, Guangua, Mecha and RIR was 1191, 1186, 1054, 1222, 1038, 1249, 1257 and 1394 g and their mean daily body weight growth rates were 7.6, 7.5, 6.7, 7.8, 6.6, 7.9, 8.0 and 8.8 g per bird, respectively. The native chicken lines named as Mello-Hamusit, Guangua and Mecha were the fastest growers among the native chicken lines. Mortality from hatching to end of the growth period i.e. at maturity was higher for all the native and RIR chickens used under intensive management condition.
显示更多 [+] 显示较少 [-]Species diversification, livestock production and income of the poor in the Indian State of Andhra Pradesh
2007
Akter, S. | Farrington, John | Deshingkar, P. | Rao, L. | Freeman, H.A.
This paper investigates the factors associated with private sector smallholder livestock and the associated income of the poor in the Indian States of Andhra Pradesh. The data used are drawn from the Livelihood Options Study led by the Overseas Development Institute, London, specifically the Census Survey 2001/2 and Panel Survey of early 2005. Poorer households depend disproportionally on livestock. Important changes were noted; the average size of any single species declined considerably in the five year period beginning from 1996/7, the number of farms keeping the species rose in the 1996/7 to 2001/2 period but dropped in the recent 2001/2 to 2003/4 period. The poorer households kept fewer small ruminants and poultry in the latter period but richer households kept more. This might suggest that the technology is shifting towards what the better off can afford like the intensive poultry keeping, and that they have better access to certain resources such as crop residues. On the other hand, policies such as the ban on grazing by goats will also have affected the poor more since they rely on open-grazing methods. Farmers identified shock/stress variables and natural environment as important for the decrease in livestock population. Livestock act as a very real means of smoothing income by allowing debts to be repaid, farm inputs and medical treatment to be purchased, and dowry to be paid. More than 22% of the farmers mentioned disease problems as a cause of the decline in livestock population. This problem needs to be addressed, possibly through public-private partnership arrangements as are being tried in other countries.
显示更多 [+] 显示较少 [-]Potential economic impact from the adoption of Brachiaria hybrids resistant to spittlebugs in livestock systems of Colombia, Mexico and Central America
2005
Rivas Ríos, Libardo | Holmann, Federico J.
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.
显示更多 [+] 显示较少 [-]Conceptual, methodological and institutional issues in participatory livestock production research
2002
Morton, J. | Adolph, Barbara | Ashley, S. | Romney, Dannie L.
This article discusses major issues that confront attempts to introduce participatory methodologies into livestock production research, based on experiences during two projects in East Africa, and interviews with researchers and others in the region. The extent to which research can be participatory is strongly influenced by the institutional contexts in which it is carried and used, and some of the institutions involved are briefly surveyed. The article then discusses conceptual issues; including the notion of degrees of participation, the underdevelopment of participatory research in livestock compared to crop science, and the reluctance of existing livestock science to deal with multiple-output systems. The relations between participatory research, whole-farm research and livelihoods research, and the role of economic analysis are also explored. Methodological issues at various points of the project cycle are discussed, including: the need to tailor methods to agreed objectives, the role of “PRA toolsâ€, the specific problems relating to participatory trials with livestock, and the role of on-station trials. Institutional issues such as funding procedures and timescales, and reward systems for researchers are generic to all participatory research, but they are perhaps felt more strongly in the livestock sector where they combine with livestock-specific issues.
显示更多 [+] 显示较少 [-]The feed values of indigenous multipurpose trees for sheep in Ethiopia: The case of Vernonia amygdalina, Buddleja polystachya and Maesa lanceolata
2008
Haile, Aynalem | Tolemariam, T.
The feed resources base, the feeding systems and feed values of three indigenous trees Girawa, Anfare and Kelewa (Local (Amharic), Ethiopian names ) were studied for sheep in sub humid, mid altitude area of south western Ethiopia. The study involved a survey of the feed resources base and assessment of the feeding systems, chemical analysis and in vitro dry matter digestibility. In addition, Girawa was selected to study its effect on growth performances using 32 lambs. The levels of Girawa used for the growth performance study in groups I, II, III and IV, respectively were 100 g/d, 200 g/d, 300 g/d and 400 g/d. The main feed resources for sheep in Jimma area were found to be natural pasture, crop residues, crop aftermaths and indigenous multipurpose trees. Grazing on natural pasture constituted the main feeding system. The indigenous trees were cut and fed occasionally. The levels of CP ranged from 186.2 to 244.4 g/kg DM with minimum level in Anfare. Higher values were recorded for Girawa. Organic matter content was higher for Anfare (924.3 g/kg DM) and lower for Girawa (877.9 g/kg DM). In vitro dry matter digestibility values were 0.448, 0.422 and 0.458 for Girawa, Anfare and Kelewa, respectively. Supplementation of Girawa had an effect (p<0.01) on live weight gains of lambs. Lambs that were offered 400 g/d of Girawa had a higher daily live weight gain (95.1 g/d) compared to those supplemented with 200 (43.3 g/d) and 300 g/d (50.5 g/d) of Girawa as well as the control group (34.0 g/d). Weight gains were not different between the control group and those supplemented with 200 and 300 g/d of Girawa. It was concluded that these feed resources represent a great potential for sheep production in areas where the resources are available. It is also suggested that more studies are needed on higher level of Girawa than the present study on animal performances along with its anti-nutritional effects.
显示更多 [+] 显示较少 [-]Hypotheses on inland valley development for smallholder dairy production in three West African countries Côte d'Ivoire, Mali and Nigeria
2007
Agyemang, K. | Yapi-Gnoare, C.V. | Ouologuem, B. | Barje, P.P. | Adediran, S.A.
A set of pre-formulated hypotheses about the potentials of inland valleys to agricultural production in general, and livestock (dairy) - based enterprises in particular, were tested with data collected from five regions comprising 71 villages/towns and 630 households in three countries (Nigeria, Mali and Côte d'Ivoire). The study was undertaken to test hypothesis concerning the potentials of the inland valleys systems to agricultural production, and those pertaining to the intensification of livestock production in the valleys systems and their relationships with demand for livestock (dairy) products. Results from the analysis showed that many of the previously held views about inland valley and their potential were supported by the data from the three countries. Most of the hypotheses relating directly with inland valley potentials were accepted in the majority of locations. However, there were few hypotheses which were not supported by data from all countries and study sites. The overall assessment from the surveys is that the potentials of the inland valleys towards dairy production are currently good in all the countries and could be better if the resources available in the inland valley environments (for example crop residues) are better managed and utilized. Intensive use of inland valleys was related more to population density than access to market. Similarly consumption levels of domestic dairy products were influenced by population concentration. Instead access to market influenced positively farmers' practices towards specialization and intensification of dairy production. Increase demand for milk and dairy products is met by intensification and not by increase in herd size. Efforts to ensure continued milking through feeding was not related to herd size. As revenues (sales and home consumption) increased, more lands were left to fallow. These results confirm the assertion that the presence of inland valley systems for cropping and livestock rearing promotes diversification of agriculture, and presumably reduces farmers' production risks.
显示更多 [+] 显示较少 [-]Anthelmintic effect of Halothamus somalensis in Arsi-Bale goats
2005
Dawo, F. | Tibbo, Markos
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.
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