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Role of traditional enclosures on the diversity of herbaceous vegetation in a semi-arid rangeland, southern Ethiopia
2010
Angassa, A. | Oba, G. | Treydte, A.C. | Weladji, R.B.
Grazing management and seasonality strongly influence the recovery potential of herbaceous vegetation in semi-arid rangelands of southern Ethiopia after history of heavy grazing. We investigated effects of management (enclosures versus grazed landscapes), age of enclosures and seasonality related to rainfall (i.e., independent variables) on herbaceous biomass, grass basal cover, herbaceous species abundance, species richness and diversity in a savanna rangeland of southern Ethiopia. We further assessed the relationship between the herbaceous biomass and species richness. Management significantly affected most of the herbaceous response variables (i.e., comparing enclosures and open grazed). Herbaceous biomass, grass basal cover, herbaceous species richness and diversity were greater in enclosures than in grazed areas. Rainfall was also influential on herbaceous biomass, grass basal cover, abundance of herbaceous species, herbaceous species richness and diversity. Herbaceous biomass, abundance and diversity did not however vary with the age of enclosures, while herbaceous species richness appeared to decrease as the age of enclosures advanced. Grass basal cover initially decreased and later on increased with the age of enclosures, so that the older enclosures disclosed improvement of grass basal cover.
Показать больше [+] Меньше [-]Rangeland dynamics in South Omo Zone of Southern Ethiopia: Assessment of rangeland condition in relation to altitude and Grazing types Полный текст
2010
Terefe, A. | Ebro, A. | Tessema, Z.K.
Socio-economic factors influencing small ruminant breeding in Kenya
2007
Verbeek, E. | Kanis, E. | Baker, R.L. | Kosgey, I.S.
In order to design an effective small ruminant (i.e., goats and sheep) breeding program in Kenya and other areas with similar production circumstances, it is important to understand the socio-economic factors applying to the relevant production system. Information on these was obtained from a questionnaire carried out on both smallholders and pastoral/ extensive farmers in seven selected districts. From the 458 responding households, 18% kept only goats, 34% kept only sheep, and 48% kept both species. Goats were generally ranked lower in popularity. The most represented breeds in the households were the indigenous East African goat and the Red Maasai sheep, and crossbred genotypes of goats and sheep. However, according to the farmers, the pure breeds were more popular than the crossbreeds. The households owned the majority of the used land for small ruminant production. In many cases, male household members were in control of the land. Animals were in most cases owned by the household head only or by both the household head and the spouse. The most important water source for animals was the river with the frequency of watering in the dry season in some cases being as low as once a day. Both males and females made most decisions in smallholder households. Women in the pastoral/ extensive systems participated less significantly in decision making than those in smallholder households, although they were responsible to many animal production related activities.
Показать больше [+] Меньше [-]Estimation and comparison of benefits due to feeding hay and silage during the dry season on commercial dual-purpose cattle production systems in Honduras and Costa Rica
2006
Schoonhoven, A.D. | Holmann, F. | Argel, P. | Ordoñez, J.C. | Chaves, J.
Smallholders with dual-purpose cattle production systems in most Central America experience a shortage of forages during the dry season (4-8 month. As a result, substantially lower milk production and weight gain occurs. Dual-purpose operations seeking to maximize milk and beef production in the dry season can produce and feed hay or silage to their livestock. The increase in milk and beef production due to feeding hay or silage during the dry season on commercial dual-purpose cattle productions systems, the production costs of making silage or hay and the benefits as a result of feeding silage or hay are estimated and compared in Honduras and Costa Rica. Due to feeding silage or hay, farmers in Honduras and Costa Rica have increased milk production during the dry season. The costs of feeding hay are lower in both countries, although farmers feed a higher amount (kg DM/cow/ day) than silage. Feeding silage or hay to milking cows is profitable in both countries. The income-cost ratio and the net benefit ($/ cow/day) due to feeding these feedstuffs are positive. Farmers with milking cows in Honduras realise a higher income-cost ratio and net benefit due to feeding silage and hay than farmers in Costa Rica. Likewise, beef cows or young livestock supplemented with these feeding alternatives don't loose weight during the dry season. In Honduras as well in Costa Rica, it is profitable to feed silage or hay to beef cows or young livestock. Currently, no silage and a small hay market exist in Honduras. Possibly, these will develop due to an increasing demand for these profitable feedstuffs. In Costa Rica thanks to the efforts of agricultural organisations, a hay market of different qualities is developing.
Показать больше [+] Меньше [-]Participatory comparison of three pig fattening methods in the provinces of Sanguié and Boulkiemdé, Burkina Faso = Comparaison participatoire de trois méthodes d'engraissement des porcs dans les provinces du Sanguié et du Boulkiemdé au Burkina Faso
2004
Bosma, R.H. | Zongo, L.C. | Sané, A. | Zoungrana, C. | Soudré, A.
Development programs recommend fattening of pigs aged between 1 and 2 years by supplementing their local diet with industrial cereal bran, to improve womens' income. At the best moment to start this activity, just after the rainy season, high demand for these pigs induced higher prices and low margins. The start after the rainy season does not fit in the existing production system as farmers sell their surplus pigs before and during the rainy season. Traditional pig fattening lasts 3 years. About 60 women in 8 villages tested early fattening of young piglets. Piglets of the treatment were supplemented with a special concentrate and showed higher daily weight gains compared to the traditionally fed group. The gross margin of the early fattening was equal to the recommended pig fattening, but the first solved problems related to availability of piglets and thus fits better in the existing production system. Almost half of the early fattened pigs were sold within a year. Most of the women appreciated the experiment positively and suggested positive margins can be attained by selecting suitable piglets and rigorously respecting feeding and management schemes. Criteria were developed for selecting the most suitable piglets with a simple tailor tape. A projection on 3 years shows that the gross margin of early fattening is higher compared to traditional fattening and that it facilitates the production of more meat against lower cost.
Показать больше [+] Меньше [-]Evolution of milk production systems in Tropical Latin America and its interrelationship with markets : An analysis of the Colombian case Полный текст
2003
Holmann, Federico J. | Rivas Ríos, Libardo | Carulla, Juan E. | Rivera, B. | Giraldo, Luis Alfonso | Guzmán Pérez, Silvio | Martínez, M. | Medina, A. | Farrow, Andrew
The objectives were to: (1) identify and quantify the effect of technological change on productivity, profitability, and competitiveness in different milk production systems and regions of the country; (2) analyze the relationship between productivity, technological change, profitability, and competitiveness; (3) analyze the evolution of milk production systems in Colombia; and (4) discuss the market concentration and its impact on the formation of milk price. Data came from a survey to 545 farms during the year 2000 in five regions: Caribbean and Piedmont in the lowlands, Coffee Growing, Antioquia, and the Cundiboyacense altiplanicie in the highlands. The survey was designed to quantify inputs and products in order to determine costs and prices at the farm level in order to calculate (a) variable costs for feed supplementation, labor, health, reproduction, fertilization, and irrigation; (b) gross income from the sale of milk and beef, and (c) to characterize farms according to productivity level and management practices. The statistical analysis of multiple correspondence and general linear models were used to explain the variability observed between productivity and profitability as a function of technological change. Independent of the production system or the region where farms were located, the increase in competitiveness was in direct relationship with herd size. Thus, as herd size increased, production costs per unit of milk and beef decreased, net incomes per cow increased, and the return to capital investment improved. However, when this increase in competitiveness was associated with increases in productivity, this trend was not observed, which suggested that highly productive farms were not necessarily competitive. The dual-purpose system was the most profitable one in the Piedmont, Caribbean, and Coffee growing regions while in Antioquia and in the Cundiboyacense altiplanicie the most profitable was the specialized dairy system. With regards to technological change, the adoption of improved pastures and the investment in pasture divisions for a more efficient rotation generated higher productivity and income in all regions and production systems, as well as increased competitiveness through a reduction in production costs per unit of milk and beef. The use of strategic feed supplementation to the basal diet of forage had mixed effects. The best economic response to this supplementation in lowland regions (i.e., Piedmont and Caribbean) was with low quantities (i.e., < 0.5 kg DM/cow/day) of feed supplements while in highland regions (i.e., Coffee Growing area, Antioquia and the Cundiboyacense altiplanicie) was with moderate quantities (i.e., between 0.5 and 2 kg DM/cow/day). The use of fertilization and irrigation increased productivity, but reduced net income and increased production costs, except in the Cundiboyacense altiplanicie. The practice of milking twice a day increased both productivity and profitability and reduced production costs, except in the Caribbeanregion. Farms that de-wormed milking cows with low frequency against internal and external parasites obtained higher incomes and lower production costs in comparison with farms that de-wormed cows with higher frequency although there were no differences in productivity. The amount of years of experience of farmers at producing milk was a key factor to increase profits, although not productivity. Farms located in sites where the commercial value of land was high (>US$6,000/ha) and near market centers had higher productivity that those with commercial value of land medium ($3,000 to $6,000/ha) and low (<$3,000/ha) but were less profitable in all regions. Box 1: Recommendations to researchers and extensionists Identify profitable technologies. Technologies that increase productivity are not necessarily profitable, which suggest the need to determine appropriate ways to evaluate them economically. This was the case of fertilization and irrigation. It is necessary to determine the best economic response to various levels of N2 and H2O to different species of improved grasses under various soil types and conditions. The most competitive and profitable breed group in the dual-purpose system was the crossbred with low (24% European-76% Zebu genes) and medium levels of dairy genes (55% European-45% Zebu genes) but had lower productivity than the purebred group (98% European genes). In the specialized dairy system, the purebred group was slightly more profitable, productive and competitive than the crossbred group with medium level of dairy genes, but this difference was not significant. The Colombian dairy sector has become more productive and competitive, but less profitable. Comparing the evolution of dairy farms with studies 12 years ago, milk production per hectare increased by 44% in dual-purpose herds and 14% in specialized dairies. This increase in productivity reduced the milk production cost by 16% and 10% in dual-purpose and specialized dairies, respectively, due to an increase in stocking rate by 15% and 17% in dual-purpose and specialized dairies as well as to an increase in investment in infrastructure and equipment by 258% and 37% in dual-purpose and specialized dairies, respectively. However, the net income per hectare during this period decreased by 27% and 69% in dual-purpose and specialized dairies due to a reduction in the producer's price of milk and beef of 22% and 20% in dual-purpose systems, and of 41% and 27% in specialized dairies. Nevertheless, this reduction in price to producers was never translated in lower prices to consumers, but remained in the hands of supermarkets and milk processing plants which expanded and modernized with long-life technology. Development agencies must internalize the fact that policies oriented to markets will be increasingly "oriented to supermarkets". If one adds that in Colombia exists 3 or 4 supermarket chains that control the food retail market, the conclusion is that sectoral policies will need to learn how to deal with a handful of giant companies. This in a huge challenge, and demands an urgent review of ideas and strategies. Box 2: Recommendations to decision makers Regionalize research. Due to the fact that the most profitable production systems are region-specific, Colombia should have different strategies for research and technology transfer in order to exploit more efficiently the comparative advantages of each region and production system. Promote collective action. It is necessary to promote cooperatives and associations to help small producers to adapt to new patterns with higher levels of competition. Otherwise, the new rules of the game could induce a massive exodus of producers in the short term and in a relatively brief period of time. It is possible, in the short run, to adopt technologies that increase milk productivity and reduce production costs while profits are reduced as a result of falling real prices as occurred in Colombia during the 90's. However, in the long run, this situation is simply unsustainable. The proposals and challenges presented in this case study have illustrated the problems and opportunities of the dairy sector in Colombia. However, these systems could represent similar situations in other countries of Latin America. Given the phenomenon of globalization and higher degree of efficiency that these systems are being exposed to, the issues of productivity, technological change, competitiveness, and markets, are critical and of enormous relevance for the performance and survival of the livestock sector in the next decades. Box 3: Recommendations to producers Without research there is no future. Efficiency goes hand in hand with technology and this depends on research and technology transfer. However, public funds allocated to agricultural research are being reduced. The challenge consists that producers in Colombia take greater control of livestock research by building alliances with local, regional and international organizations leaders in forage and livestock research. For this it is necessary that producers define and fund their own research agenda. Production-to-consumption participation. In the coming years, producers cannot limit themselves to participate only in the primary phase of production, but to expand their scope of action to other phases of the market chain to have a higher participation in the formation of milk prices and to capture a greater piece of the final price.
Показать больше [+] Меньше [-]Normal haematological values of Galla goats in Kenya Полный текст
1989
Wesonga, H.O. | Nandokha, E.
Haematological values of healthy Galla goats have been determined. These values have been found to differ from those reported by other authors in different breeds of goats from various countries. Those values found to be of highly significant difference (P
Показать больше [+] Меньше [-]The effect of nitrogen and sulphur fertilization on tiller formation and grain yield of spring wheat
2005
Siaudinis, G.(Lithuanian Inst. of Agriculture, Akademija, Kedainio reg. (Lithuania))E-mail:[email protected] | Lazauskas, S.(Lithuanian Inst. of Agriculture, Akademija, Kedainio reg. (Lithuania))E-mail:[email protected]
In 2003 and 2004, field experiments with spring wheat (Triticum aestivum L.) were carried out at the Lithuanian Institute of Agriculture in Dotnuva, Lithuania. The aim of the study was to evaluate the effect of nitrogen and sulphur fertilizers on tiller formation and grain yield of spring wheat (variety 'Munk'). N and S fertilizers were applied at 3 rates: N (0, 60 and 120 kg haE-1) and S (0, 15 and 30 kgE-1 ha). Both years, N fertilization had a significant effect on tiller formation. At harvest, the total number of tillers was approximately 0.5 tillers higher in the plots with the application of N120. The growing season in 2003 was comparatively dryer, and a significant increase in grain yield was found - up to 60 kg haE-1 of N. Due to higher rainfall in 2004, grain yield was much higher and the highest effect was found with the maximum N supply - 120 kg haE-1. One thousand grain weight was influenced by the year, while fertilizers did not have any significant effect. The impact of S fertilization on the number of tillers and final grain yield was insignificant; nevertheless S fertilization increased the concentration of S in the aboveground plant mass.
Показать больше [+] Меньше [-]The development of aquaculture in Turkey
2005
Canyurt, M.A.(Ege University (Turkey))E-mail:[email protected]
Turkey has rich inland water sources, about 200 natural lakes, about 750 artificial lakes or ponds, about 193 reservoirs, 33 rivers and streams of 177,714 km length and 8333 km of coastal strips. Some lagoons covering of 70,000 ha in Aegean and Mediterranean coastal strips are very suitable for aquaculture. The main fish species cultured in Turkey are carp (Cyprinus carpio), rainbow trout (Oncorhynchus mykiss), Atlantic salmon (Salmo salar), gilthead sea bream (Sparus aurata), European sea bass (Dicentrarchus labrax), bluefin tuna (Thunnus thynnus), Blackl sea turbot (Pselta maxima), Mediterranean mussel (Mytilus galloprovincialis) and shrimp (Penaeidae spp). Aquaculture production of Turkey has grown steadily over the years from 5,782 t in 1990 to 63,000 t in 1999 and to 79,031 t in 2000. There are 1309 farms in inland water producing approximately 32,466 t of fresh water fish species and 352 farms at sea producing 40,119 t of sea fish species, mainly Gilthead sea bream and European sea bass.
Показать больше [+] Меньше [-]System modelling of the grain drying process
2005
Arhipovs, S.(Latvia Univ. of Agriculture, Jelgava (Latvia))E-mail:[email protected]
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.
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