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Traditional poultry production and commercial broiler alternatives for small-holder farmers in Botswana Texte intégral
2000
Aganga, A.A. | Omphile, U.J. | Malope, P. | Chabanga, C.H. | Motsamai, G.M. | Motsumi, L.G.
Two studies were conducted: the first study evaluated the production potential of indigenous (Tswana) chickens under an extensive free-range management system in the Gaborone agricultural region of Botswanal; and the second study was a survey of 25 randomly selected, commercial small-scale broiler farms in the Southern region of Botswana. Data were obtained using a structured questionnaire, interviews and direct observations of the birds and their management in the two systems. Study 1 involved 85 farmers. Ten different common supplementary feeds fed to the free-range chickens together with soil samples from where the chickens roost were collected. The feeds were: sorghum grain (Sorghum bicolor), maize grain (Zea mays), jugo bean, also known as bambara groundnut (Vigna subterranea), tepary bean (Phaseolus acutifolius), millet grain (Pennisetum glaucum), melon seeds (Colocynthis citrullus [Citrullus lanatus]), Tswana water melon fruit (whole), sorghum milo, maize bran and sorghum beer residue (moroko). Mean adult body weight of the birds (n=713) was 2.2 and 2.0 kg for cocks and hens respectively. Average egg weight (n=188) was 48 g with an annual production of 34 eggs laid in 2 to 3 clutches. Production varied little among flocks. Sexual maturity was attained at about 6 months for females. The crude protein content of the feeds (as-fed basis) given as supplements was: maize grain 9.8%, millet 6.5%, sorghum 11.1%, tepary bean 18.5% and jugo bean 15.8%. All the feeds had a low level of calcium, for example 0.22% for melon seeds. The farmers kept the chickens for home consumption and occasional sales. In study 2, all the farmers practiced intensive housing on deep litter. The number and size of the poultry houses ranged from one to eight, with floor area of less than 100m2 to 1000m2. Numbers of chickens in each batch ranged from less than 1000 to 10000 with about 4 batches in a year. The broiler strains were Ross hybrid, Indian River and Cobb with 56% of the farmers keeping Ross hybrid. Various heating methods were used for brooding with more than 40% using gas as a source of heat. Vaccinations for either gumboro and/or Newcastle were used by 76% of the farmers. Feed was provided ad libitum in all instances.
Afficher plus [+] Moins [-]Characterizing husbandry practices and breeding objectives of Sheko cattle owners for designing conservation and improvement strategies in Ethiopia Texte intégral
2014
Bayou, E. | Haile, Aynalem | Gizaw, Solomon | Mekasha, Yoseph
A survey was conducted through single field visits and interviews with 360 respondents in selected districts of Bench Maji Zone, Southwestern Ethiopia to asses the Sheko cattle farming system, breeding practices, and identify cattle breeding goals and constraints for designing Sheko cattle conservation and improvement strategies. The total populations of Sheko cattle herd structure in the sampled districts within each PA obtained by counting directly on the field were estimated to be 2813.Under random mating, the inbreeding coefficient was higher in midland (1.72) than in lowland (1.35) agro ecological zones (AEZs). The mean Sheko cattle herd size per household was 1.09 in midland and 1.29 in lowland AEZs. About 93.9% and 88.3% of the households, respectively, in midland and lowland do not have breeding bull. Random mating predominates in both midland (87.2%) and lowland (85%) AEZs. The reported peak season of mixing of the different Sheko cattle herd within a village start after the crop aftermath (February to May) was picked from the cultivated land, whereas, beginning from main rainy season in June to the end of crop harvesting time usually on January smallholder farmers in both AEZs keep their cattle separately. The observed male to female mating ratio was 1:16.4 in midland and 1:8.6 in lowland. Sheko bulls were castrated at the age of 4.2 and 4.8 years in midland and lowland respectively. Appearance/conformation was the most important trait in choosing of breeding male for both midland and lowland small holder Sheko owners. Whereas, milk yield was the most important trait for the choice of breeding cows in both AEZs. The purpose of keeping Sheko cattle in midland area was for draught followed by milk, income, saving and dowry, in that order. In lowland agro ecology milk production, draught power, and income generation are the purposes for keeping Sheko cattle. In both AEZs feed shortage, disease and labor shortage were the most important cattle production constraints in that order. It has been found that an integrated system approach to breed conservation and improvement needs to incorporate traits sought by the cattle keepers, the multiple roles of cattle, and the existing traditional herding and breeding practices.
Afficher plus [+] Moins [-]Small ruminant production in coffee-based mixed crop-livestock system of Western Ethiopian Highlands: Status and prospectus for improvement Texte intégral
2010
Shenkute, S. | Legasse, G. | Tegegne, Azage | Hassen, A.
Small ruminant production in coffee-based mixed crop-livestock system of Western Ethiopian Highlands: Status and prospectus for improvement Texte intégral
2010
Shenkute, S. | Legasse, G. | Tegegne, Azage | Hassen, A.
The study was conducted in Goma district of Jimma Zone of Ethiopia with the objectives of documenting the reasons why farmers in coffee dominant mixed-farming systems of western Ethiopia keep small ruminants, and identifying the constraints and opportunities for improvement of this sector. Results are based on diagnostic survey of 160 sample households, group discussions and personal observation. The study district was stratified into three groups based on flock distribution as: sheep dominating, goat dominating and mixed flock sites. The average land holding per household was 1.93 ha. In Goma where coffee and chat are the major cash sources for farmers, small ruminant are also primarily kept for cash generation as reported by 94% of the sampled households. The second main reason for keeping small ruminant in the study area was for saving mainly in time of coffee failure. Keeping small ruminants as a source of manure was the third important reason. From the interviewed households, 59.4, 32.1, 23.5, and 19.4% of them utilize communal grazing, aftermath grazing, roadside grazing, and riverside grazing, respectively for their animal as a sources of feed. Most small ruminants are either tethered or herded all the seasons due to the cultivation of perennial crops and predators. All small ruminants are housed for protection from adverse weather conditions and predators. The major problems for small ruminant production and marketing were: feed and grazing land shortage, lack of input, predators, diseases and parasites and marketing problems. In order to exploit the current growing demand of small ruminant meat at local and international markets, research and development interventions are required with regard to the identification of alternative feed resources and strategic feeding management, identification of causes of diseases and their control methods and improving marketing efficiency through appropriate policy.
Afficher plus [+] Moins [-]Small ruminant production in coffee-based mixed crop-livestock system of Western Ethiopian Highlands: Status and prospectus for improvement Texte intégral
2010
a. hassen | azage tegegne | s. shenkute | g. legasse
The study was conducted in Goma district of Jimma Zone of Ethiopia with the objectives of documenting the reasons why farmers in coffee dominant mixed-farming systems of western Ethiopia keep small ruminants, and identifying the constraints and opportunities for improvement of this sector. Results are based on diagnostic survey of 160 sample households, group discussions and personal observation. The study district was stratified into three groups based on flock distribution as: sheep dominating, goat dominating and mixed flock sites. The average land holding per household was 1.93 ha. In Goma where coffee and chat are the major cash sources for farmers, small ruminant are also primarily kept for cash generation as reported by 94% of the sampled households. The second main reason for keeping small ruminant in the study area was for saving mainly in time of coffee failure. Keeping small ruminants as a source of manure was the third important reason. From the interviewed households, 59.4, 32.1, 23.5, and 19.4% of them utilize communal grazing, aftermath grazing, roadside grazing, and riverside grazing, respectively for their animal as a sources of feed. Most small ruminants are either tethered or herded all the seasons due to the cultivation of perennial crops and predators. All small ruminants are housed for protection from adverse weather conditions and predators. The major problems for small ruminant production and marketing were: feed and grazing land shortage, lack of input, predators, diseases and parasites and marketing problems. In order to exploit the current growing demand of small ruminant meat at local and international markets, research and development interventions are required with regard to the identification of alternative feed resources and strategic feeding management, identification of causes of diseases and their control methods and improving marketing efficiency through appropriate policy | S. Shenkute, G. Legasse, Azage Tegegne, A. Hassen, 'Small ruminant production in coffee-based mixed crop-livestock system of Western Ethiopian Highlands: Status and prospectus for improvement', Livestock Research for Rural Development, 2010
Afficher plus [+] Moins [-]Transgressive segregation for rain quality traits in the crossings between covered and hull-less barley Texte intégral
2010
Bleidere, M., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia)
The objectives of the investigation were to determine the transgressive lines of spring barley (Hordeum vulgare L.) for grain quality traits (1000 kernel weight, and content of crude protein, starch and β-glucans) in the six cross combinations between covered and hull-less barley genotypes. The trial was carried out at the State Stende Cereal Breeding Institute during 2007 and 2008. Lines representing either positive or negative transgression were found in each cross combination if compared covered and hull-less lines with their parent varieties. These lines during the two years of investigation exceeded both parents in positive or negative direction by one standard deviation according to any of the four analyzed grain quality traits. Seven positive transgressive lines were observed regarding 1000 kernel weight, and two transgressive genotypes regarding crude protein content within the population of covered barley lines. No line with positive transgression regarding starch and β-glucan content was found within the covered barley population. 27 hull-less lines showed positive transgression regarding any of the four analyzed grain quality traits. The results show that it is possible to increase grain quality of spring barley grain by implementing selection practices.
Afficher plus [+] Moins [-]Characteristic of grain quality for early generation lines in the crossings between covered and hull-less barley Texte intégral
2009
Bleidere, M., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia) | Belicka, I., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia)
The objectives of the investigation were to determine effect of hull-less gene on grain quality traits (crude protein, starch and β-glucans) and to evaluate the heritability of these traits in the F4 and F5 generations of six crosses between covered and hull-less barley (Hordeum vulgare L.). The trial was carried out at the State Stende Cereal Breeding Institute during the years 2007 and 2008. Mean value, range and the coefficient of variation of traits for covered and hull-less lines within each cross combination were calculated. Heritability of quality traits was estimated as intergeneration correlation (r) and linear regression coefficients (b). The highest intergeneration correlation values were observed for starch content within covered and hull-less barley populations (rF4:F5=0.609 and 0.635 respectively). Moderate intergeneration relationship was observed for crude protein content within covered barley population (r=0.582), and for β-glucans content within hull-less barley population (r=0.593). The regression estimates of heritability were higher for starch content for both covered and hull-less barleys (b=0.549 and 0.703 respectively). Due to effects of genotype and environment interactions the regression estimates of heritability for crude protein and β-glucans content for both covered and hull-less barley were low (b varied from 0.347 to 0.373).
Afficher plus [+] Moins [-]Effects of growing location and variety on free tryptophan and mineral nutrient content in wheat Texte intégral
2009
Lundegaardh, B., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Centre for Sustainable Agriculture | Jastrebova, J., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science | Zhokhov, S., Swedish University of Agricultural Sciences, Upsala (Sweden). Dept. of Chemistry | Maartensson, A., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Soil and Environment | Oeborn, I., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Plant Production Ecology
Tryptophan (Trp) is an essential amino acid for mammals since they cannot synthesise it. Wheat (Triticum aestivum L.) is a major source of dietary Trp, and wheat high in Trp would thus be very beneficial. This study investigated the impact of location and wheat variety on the content of free Trp and mineral nutrients in wheat grain. Four wheat cultivars from national variety tests on wheat with varying protein contents were selected from seven different locations of Sweden representing different climatic zones and soil contents of trace elements. Grain was analysed for Trp content using reversed phase HPLC. Mineral nutrients were analysed using inductively coupled plasma emission spectrometry. Wheat yield and grain content of nutrients and Trp differed significantly between sites. High N content in grain was correlated with a high content of Cu, Fe and S, and also Ca and Mg. However, it was correlated with a low content of K and Na. Trp content was positively correlated with Na and Zn content and negatively correlated with K/Na and K/(Na+Zn) ratio. The varieties differed in Trp content and the two ratios, but there were no significant differences in yields between the varieties at any location. The results indicated salt stress induction of Trp synthesis, which may protect wheat against salt stress and yield losses.
Afficher plus [+] Moins [-][Factors that influence the starch content in winter rye] Texte intégral
2009
Poisa, L., Latvia Univ. of Agriculture, Jelgava (Latvia);Agricultural Science Centre of Latgale, Vilani, Rezekne reg. (Latvia)
The EU Directive on the promotion of the use of biofuels or other renewable fuels for transport (CO M 2003/30/EC) states that the proportion of biofuels in 2010 must make 5.75% of non-renewable fuels, but in 2020 - 10%. The only way for Latvia to fulfil the Directive 2003/30/EC is to use winter rye because it is one of the oldest cereals grown in Latvia, and Latvia has a long-lasting experience in growing it. A field trial of winter rye (Secale cereale L.) was arranged in the Agricultural Science Centre of Latgale from 2005 to 2007. The influence of four winter rye varieties and five fertilizer rates on grain yield and starch content was researched for three years. The year (factor A), the varieties (factor B), the fertilizer rates (factor C), and the interaction of factors AB, AC , BC, and ABC significantly influenced the yield of grain and the starch content with 95% probability. It is recommended to use good quality grain with high starch content and low protein content for bioethanol production. The varieties of winter rye 'Kaupo', 'Amilo', and 'Walet' are the most suitable for ethanol production in Latgale region.
Afficher plus [+] Moins [-]Development of driving cycles for dynamometer control software corresponding to peculiarities of Latvia Texte intégral
2009
Dukulis, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Pirs, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
Performing biofuel use studies, a large number of parameters that characterize engine operation under different conditions and with different fuel mixtures have to be identified. The real driving conditions are usually simulated by driving cycles on a laboratory chassis dynamometer. There are two major categories of driving cycles: legislative and non-legislative. From the viewpoint of cycle formation there are also two ways. One is composed of various driving modes of constant acceleration, deceleration and speed, and is referred to as modal or polygonal. The other type is derived from actual driving data and is called as 'real world' cycle. There is a strong agreement among researchers that driving characteristics of each city are unique because of different vehicle fleet composition, driving behaviour and road network topography. It is therefore better to develop own driving cycles than using driving cycles developed elsewhere. The aim of this investigation is to develop driving cycles or models for dynamometer control software corresponding to peculiarities of Latvia. The procedure for cycle development and fuel consumption and exhaust emissions measurement was worked out. Using real driving data on the Jelgava streets, models simulating driving in different urban areas were constructed. The model quality was determined using vehicle driving parameters and fuel consumption measurement results from both the road and laboratory tests. Since the obtained data coincidence of all the parameters exceeded 98%, the elaborated cycles can be used for the biofuel use efficiency determination.
Afficher plus [+] Moins [-]Methodology of dietary fibre determination in grain products Texte intégral
2009
Ozolina, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Gramatina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kunkulberga, D., Latvia Univ. of Agriculture, Jelgava (Latvia)
The dietary fibre is edible parts of plants' carbohydrates that are resistant to digestion in human small intestine. Diets naturally rich in dietary fibre support to prevent constipation, improve gastrointestinal health, glucose tolerance and the insulin response, and reduce the risk of colon cancer, hyperlipidemia, hypertension and other coronary heart disease risk factors. About 45% of the dietary fibre intake comes from grains and grain mixtures. In Latvia, there are neither data, nor investigations of the dietary fibre content in grain products during processing and in the end products in which manufacturers and consumers are interested. The aim of this paper was an approval of dietary fibre determination methodology by using analytical equipment the Full option science system (FOS) Analytical Fibertec E 1023. The dietary fibre determination experiments were carried out in the Research Laboratory of the Department of Food Technology at the Latvia University of Agriculture in 2009. The Total Dietary Fibre (TDF) content was analyzed in the samples of rye whole grain flour, rye whole grain bread, and wheat biscuit. Experiments showed that the fibre content in rye whole grain flour is 13.8 g 100 gE-1, in rye whole grain bread - 11.6 g 100 gE-1, and in the wheat biscuit - 1.9 g 100 gE-1. Reached data are comparable with results of other researchers' data.
Afficher plus [+] Moins [-]Inhibition of microbial growth of a salad with meat in mayonnaise by different packaging technologies Texte intégral
2009
Levkane, V., Latvia Univ. of Agriculture, Jelgava (Latvia) | Muizniece-Brasava, S., Latvia Univ. of Agriculture, Jelgava (Latvia)
The objective of the research was the shelf life extension of a salad with meat in mayonnaise. The microbial stability of the salad with meat in mayonnaise packaged under vacuum, in modified atmosphere, and using 'Sous vide' technology was examined and compared with conventionally packaged (in ambient air) salad. The salads were packaged in polyamide/polyethylene pouches with barrier properties as well as in pouches made from biodegradable plasticized poly-β-hydroxybutyrate or polylactic acid film. Control samples without preservatives were packed in traditional polypropylene containers covered with non-hermetic lids. PURASA L Powder Opti Form (sodium lactate) in the amount 5 g kgE-1, 10 g kgE-1, and 15 g kgE-1, and ethyl alcohol in the amount of 2 ml were used as single preservatives for separate samples. The studies of the samples were carried out after 1, 3, 7, 10, 15, 18, 25, 29, 42, and 52 storage days at the temperature of +4+-0.5 deg C. Experimentally the quality of the salad with meat in mayonnaise was characterized by measuring the total plate count of microorganisms. The obtained results indicate that different packaging technologies and addition of preservatives show significantly different influence on the microbial growth in different samples. 'Sous vide' packaging technology was effective for the shelf life extending and guarantee of safety of the salads with meat in mayonnaise.
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