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Genetic diversity and relationship of indigenous goats of Sub-saharan Africa using microsatellite DNA markers Полный текст
2009
Muema, E.K. | Wakhungu, Judi W. | Hanotte, Olivier H. | Han Jianlin
Sub-Saharan African goats with an estimated population of 180 millions are major asset for farmer communities in a range of agro-ecological zones. This study was undertaken to determine the genetic diversity in and differentiation of relationships among 18 populations of goats from Uganda (4), Tanzania (5), Kenya (2), Mozambique (2), Nigeria (3), Mali (1) and Guinea Bissau (1). Heterozygosity, estimates of FST, genetic diversity and distances were performed using data from 11 microsatellite DNA loci. Expected heterozygosity ranged from 0.450 in Guinea Bissau population to 0.541 in Mbeya population (Tanzania), while the observed heterozygosity ranged from 0.441 in Pafuri population (Mozambique) to 0.560 in Sebei population (Uganda). Mean number of alleles (MNA) per population ranged from 3.82 to 5.91. Gene differentiation (FST) among populations was low (5.3%), a result confirmed by genetic distances (DA). Our results reveal that genetic relationships between populations reflect their geographical proximity rather than morphological classification.
Показать больше [+] Меньше [-]Evaluation and characterization of semen quality in rams of Menz, Dorper and Awassi crosses in different seasons in Ethiopia Полный текст
2020
Goshme, Shenkute | Banerjee, S. | Rekik, Mourad | Haile, Aynalem | Yitagesu, E. | Getachew, T.
Reproductive and productive performance of Doyogena sheep managed under a community-based breeding program in Ethiopia Полный текст
2022
Habtegiorgis, K. | Getachew, Tesfaye | Haile, Aynalem | Kirmani,, M. | Jimma, A.
The objective of this study was to evaluate growth and reproductive performance of Doyogena sheep in Ethiopia. Records used in the study were collected from (2013 to 2018). For this study, 2990 records of selected animals for economically important growth, and reproductive traits were considered. Studied traits were birth weight (BWT), 3-month weight (WWT), 6-month weight (SMWT), daily gain from birth to weaning (ADG0-3), daily gains from weaning to 6-month(ADG3-6), daily gain from birth to 6-month age (ADG0-6), litter size (LS), lambing interval (LI), age at first lambing (AFL) and annual reproductive rate (ARR). The data were analyzed using general linear models of SAS program. The overall least-squares means (LSM± SE) for BWT, WWT, and SMWT were 3.05±0.02; 14.8±2.49, and 22.8±0.22 kg respectively. The overall LSM±SE for reproductive performance: LS, LI, ARR, and AFL were 1.56±0.02 lambs, 281.22 ± 8.8 days, 2.16±0.06 lambs, and 437.43±31 days, respectively. The poor rainy season had heavier WWT (14.44 kg) than the main rainy (13.95 kg) and dry seasons (14.12 kg). Single-born lambs had higher BWT and WWT. The BWT (3.13 kg), WWT (14.84 kg), and SMWT (23.22 kg) of male lamb had higher than female BWT (2.88 kg), WWT (13.50, kg), and SMWT (20.59 kg). Parity six and parity seven lambed ewes had larger litter sizes. The lambing interval of ewes was slightly influenced by ewe parities and the first parity ewes lambed was the longer lambing interval. Different fixed effects influenced both reproductive and growth performances and need to be considered during the selection program. Phenotypic performance for most of the studied traits has shown promising results. Thus, continuation of selection is therefore recommended for bringing further improvement in the performance of Doyogena sheep.
Показать больше [+] Меньше [-]Livestock feed resources: Current production and management practices in central and northern rift valley provinces of Kenya Полный текст
2011
Lukuyu, Ben A. | Franzel, Steven | Ongadi, P.M. | Duncan, Alan J.
Smallholder dairy farmers in developing countries face many feed constraints such as inadequate feed quality and quantity, poor storage facilities for feed conservation as well as insufficient water. However, feeding of livestock continues to pose many problems due to lack of information on composition and utilization of locally available feed resources. These problems are aggravated by lack of access to and high cost of feed inputs. The use of cheap and readily available local feed resources has great potential to increase livestock productivity. The East African Dairy Development project in Kenya, through use of various participatory rapid appraisal tools conducted a rapid appraisal study of three project areas. The objective was to assess feeds and feeding practices in smallholder dairy systems, identify feed resources available year round and where the gaps are as well as to determine what practices are available for improving production and utilization of feed resources in order to raise smallholder dairy production. Established opportunities for improvement include on-farm production and utilization of fodder, efficient storage, processing and utilization of crop residues, pasture improvement, appropriate water harvesting technologies, formulation of feed rations amongst small scale farmers, small scale feed conservation as well as development of fodder markets. Given the complex farming system within which smallholder farmers operate, changes are needed in both the technologies used for improving feeds and feeding systems and in the institutional and policy arrangements surrounding feed supply. In addition, technical interventions need to be developed in a participatory manner along with farmers and other stakeholders within the system to make them relevant and sustainable.
Показать больше [+] Меньше [-]Ex-ante evaluation of forage technologies in Peru, Costa Rica, and Nicaragua Полный текст
1999
Holmann, Federico J.
The objective was to perform an ex-ante economic evaluation of new, legume-based forage alternatives available to farmers in Latin American tropical lowlands. These alternatives included grasses of the Brachiaria genus and the legumes Stylosanthes guianensis, Cratylia argentea, and Arachis pintoi. Case studies, involving farmers participating in the CIAT-led Tropileche Consortia convened by ILRI, were conducted in the forest margins of Pucallpa (Peru) and in the hillsides of the dry tropics of Esparza (Costa Rica) and Esquipulas (Nicaragua). A linear programming farm model developed by CIAT to maximize income was used for this analysis. Animal management parameters were based on farm averages at each reference site evaluated so that they represented current management conditions. Similarly, the model incorporated the prices of inputs and products typical of each country. A constant herd size was assumed for all alternatives evaluated. Production costs per kilogram of milk were estimated as the maximum expression of competitiveness, using three cow productivity parameters: the current average production per lactation (800 kg in Peru, 1,000 kg in Nicaragua, and 1,350 kg in Costa Rica); and two postulated parameters: 1,500 kg/lactation and 2,000 kg/lactation. For all forage options, key factors analyzed were (1) milk production costs resulting from implementing each forage alternative; (2) the investment required to establish each option, assuming the same number of milking cows and herd fertility; (3) the feasibility of obtaining credit with a local bank to invest in a forage alternative; and (4) the percentage of pasture area on the farm freed for other uses as a result of establishing one of the forage alternatives. Results indicated that the forage alternatives evaluated significantly improved the competitiveness of dual purpose farms in the hillsides of Nicaragua and Costa Rica, reducing the cost of producing milk between 13% and 37% with increased stocking rates, releasing up to 36% of area allocated to pastures. However, under current commercial banking conditions (real interest rates of 13% in Costa Rica and 18% in Nicaragua with payback periods of 5 years), the implementation of the options evaluated were not financially viable except for the establishment of Cratyla with sugarcane for dry-season feeding and Stylosanthes for pre-weaned calves. For all options to be implemented with commercial credit, a longer payback period was needed (8-10 years) and lower real interest rates (5-10%). The case of the forest margins of Pucallpa, was different, as none of the forage options evaluated, except Stylosanthes for pre-weaned calves, improved the competitiveness of farms under current management and production conditions due to low milk yields per cow and low proportion of herd in milk, which increased depreciation cost/cow to levels which were not viable. In addition, Pucallpa has an excess supply of forage biomass from a reduced herd inventory during the 80s and a limited fresh milk market which makes adoption of improved forages low attractive by farmers.
Показать больше [+] Меньше [-]Perception and practices of farmers on the utilization of sweetpotato, and other root tubers, and banana for pig feeding in smallholder crop-livestock systems in Uganda Полный текст
2015
Dione, Michel M. | Pezo, P. | Kyalo, Gerald | Mayega, L. | Nadiope, G. | Lukuyu, Ben A.
Limited access to quality feeds and reliable feed supply are amongst the priority constraints of smallholder pig production in Uganda. Among the feeds given to pigs, sweetpotato (SP), banana and other root tubers residues are common. However, information on farmers’ perceptions and practices on the proper use of these residues for pig feeding is limited. Therefore, this study aimed at assessing those aspects, as well as to identify opportunities for better use of these residues in the pig-SP systems. A qualitative survey was undertaken in Masaka and Kamuli, two districts of Uganda with high pig population and SP production. Focus Group Discussions (FGD) and Key Informant Interviews (KII) were undertaken with 80 small scale pig and SP producers and 24 key informants. Results from this study revealed that the majority of pig farmers in those districts use SP and other RTB crop residues as animal feed. During the rainy season, farmers scored high the utilization of SP crop residues, with the latter being the leading contributor to the pig diet especially in the rural area. SP crop residues are usually fed to pigs fresh without processing. Among the residues, fresh raw vines represent the largest part fed to pig (70%), as compared to roots and peels. The way these residues are offered vary, for example in peri-urban areas with easier access to commercial feeds, farmers feed the crop residues mixed with concentrates; whereas in rural areas with limited access to commercial feeds, crop residues tend to be given without supplementation. However, the full potential of SP and other RTB crop residues for pig feeding is not yet fully exploited as farmers accept that a large amount is wasted (37% in Masaka and 40% in Kamuli). In Masaka, the proportion of SP crop residues utilized at household level mostly for pig feeding was 40%, while in Kamuli was 52%. This study demonstrated that there is potential for better use of SP and other RTB crop residues as pig feed in the smallholder pig farming systems in Uganda, but the major constraint as pointed out by farmers is the poor access to technologies for preserving these resources. Therefore, there is a need for further exploration of strategies for conserving SP and other RTB crop residues during the harvesting period for use in pig feeding during times of feed scarcity.
Показать больше [+] Меньше [-]Body weight, body condition score and heart girth in indigenous Tswana goats during the dry and wet seasons in southeast Botswana Полный текст
2003
Nsoso,S.J. | Aganga, A.A. | Moganetsi, B.P. | Tshwenyane, S.O.
Body condition scoring (BCS) is a simple and easy technique, which allows subjective assessment of an animal’s body composition to help in adopting appropriate management strategy. Information on BCS is not available for indigenous Tswana goats. The aims of this study were to establish the relationships among body weight, body condition score and heart girth in indigenous Tswana goats raised under extensive and semi-intensive management during the dry and wet seasons in southeast Botswana. A total of 100 indigenous Tswana goats, owned by farmers and managed extensively, in wet and dry seasons, were used in Experiment 1; while 50 mature indigenous Tswana goats from the Botswana College of Agriculture were used in Experiment 2 in the dry season only under semi-intensive management. In both experiments, data were collected fortnightly on body weight, body condition score and heart girth for 12-20 weeks. Season significantly affected BCS, with lower scores (2.17±0.10 to 2.65±0.10) in the dry season than in the wet season (3.17±0.10 to 3.79±0.11), but has no effect on body weight or heart girth. Management did not significantly affect body condition score. There was no apparent relationship between body weight and condition score. Body weight was closely correlated with heart girth under extensive management in the wet season but not in the dry season. It is concluded that BCS is a more useful indicator of seasonal nutritional effects in goats than body weight or heart girth.
Показать больше [+] Меньше [-]Effect of pumpkin (Cucurbita maxima) seed meal as a supplementing diet to free-ranging goats on growth performance and semen quality Полный текст
2021
Maselema, D. | Chigwa, F. | Chingala, G.
Range forages consumed by free-range goats are commonly deficient in protein, energy and minerals resulting in low productivity of the goats. The main objective of this study was to evaluate the effect of whole pumpkin seed meal supplementing diet on growth performance and semen quality of free-range goats. Thirty Malawian local bucks with an initial weight of 12.4±0.3 kg and age of 6 months were studied in completely randomised design. The treatments were: free-grazing with either supplementing diet of pumpkin seed meal or soybean meal and grazing only. The supplementing diets were mixed with maize bran to make them comparable. The supplementing diets were offered to goats (500 g each goat) before grazing (7:00 am) in individual pens followed by free graze for 7h. The experiment ran for 150 days. The measurements included: feed and refusals of the supplementing diet, live body weight, scrotal circumference and semen quality characteristics. The intake of supplementing diets was high in bucks consuming soybean supplementing diet than pumpkin seed meal supplementing diet (P = 0.0489). Bucks supplemented with either soybean or pumpkin seed meal had higher final weight and average daily gain (P < 0.05) than the non-supplemented goats. However, the final live body weight and average daily gain did not differ (P = 0.639) between goats on soybean and pumpkin seed meal supplementing diets. The bucks supplemented with pumpkin seed meal had the widest scrotal circumference (P < 0.05) of all the treatments studied. The bucks fed a supplementing diet containing pumpkin seed meal had higher semen pH (P < 0.05) than bucks on sole grazing group and soybean supplementing diet. Bucks on pumpkin seed supplementing diet had the greatest scores (P < 0.05) on total sperm motility and progressive motility; and sperm concentration followed by the bucks on soybean and the bucks on grazing only had the lowest score. The whole pumpkin seed meal could be used to improve productive performance and semen quality characteristics of free-ranging bucks.
Показать больше [+] Меньше [-]Potential economic impact from the adoption of new Brachiaria hybrids resistant to spittlebugs in livestock systems of Colombia, Mexico and Central America Полный текст
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.
Показать больше [+] Меньше [-]Village chicken production systems in Ethiopia: 2. Use patterns and performance valuation and chicken products and socio-economic functions of chicken Полный текст
2003
Dessie, Tadelle | Tadesse, M. | Yami, A. | Peters, Kurt J.