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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Evaluation of fibrous feeds for growing pigs in Vietnam : effects of fibre level and breed /

Len, Ninh Thi, January 2008 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2008. / Härtill 4 uppsatser.
42

Temporal and spatial variation in predation on roe deer fawns /

Nordström, Jonas, January 2010 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2010. / Härtill 5 uppsatser.
43

Utilização de betaína em substituição parcial de diferentes fontes de metionina na dieta de frangos de corte

Silva, Leandro da 28 August 2014 (has links)
A betaína vem sendo utilizada como uma fonte poupadora de metionina na dieta de frangos de corte, tendo em vista o seu menor custo, o que reduz o custo final da dieta. Outro fator de interesse na utilização da betaína é sua função osmoprotetora, que auxilia na regulação do funcionamento celular, principalmente em períodos de estresse. Foram estudadas neste trabalho duas fontes de metionina (DL-Metionina e MHA-Metionina) em diferentes níveis de metionina+cistina, e dois percentuais de inclusão de betaína na dieta, em diferentes fases de criação. No período de 1 a 7 e de 8 a 21 dias, as aves que receberam dietas com níveis reduzidos de metionina+cistina sem a suplementação com betaína apresentaram um desempenho inferior. Quando as dietas deficientes foram suplementadas, o desempenho equiparou-se aos tratamentos positivos. Não houve diferença quanto às fontes de metionina. No período de 22 a 42 dias, a matéria seca da carcaça e os rendimentos de carcaça, peito, perna, gordura abdominal e asa não diferiram. As fontes de metionina diferiram significativamente para as variáveis consumo de ração, taxa de deposição de proteína e peso relativo do fígado. O ganho de peso apresentou resultado satisfatório quanto à utilização de betaína, sendo que a redução de 7% com suplementação apresentou desempenho igual ao controle. Quando utilizada DL-Metionina, maiores taxas de deposição de proteína foram observadas com 7% de redução da quantidade de metionina+cistina com suplementação de 500 g ton-1 de betaína. Para MHA-Metionina, o mesmo foi observado com 7% de redução de metionina+cistina e suplementação de 1000 g ton-1 de betaína. A taxa de deposição de gordura foi estatisticamente superior nos tratamentos com suplementação de betaína, porém a gordura abdominal não diferiu. / Betaine has been used as a source of sparing methionine in the diet of broilers, once its cheaper than methionine, which reduces the final cost of diet. Another factor of interest in the use of betaine is over its osmo-protector function, that assists in the regulation of cell function, especially in stress phases. In this study two sources of methionine (DL-Methionine and Methionine-MHA) were studied at different levels of methionine + cystine, and two inclusion percentage of betaine in the diet at different raising stages. From 1 to 7 and 8 to 21 days, the birds fed diets with reduced levels of methionine and cystine without betaine supplementation underperformed. When deficient diets were supplemented performance equated to the positive treatments. There was no difference as to sources of methionine. In the 22-42 days period, dry matter of carcass and carcass yield, breast, leg, wing and abdominal fat did not differ. Methionine sources differed significantly for feed intake, protein deposition rate and relative weight of liver. Weight gain showed satisfactory result considering the use of betaine, and the 7% reduction with supplementation showed equal performance to the control. When DL-Methionine was used, higher protein deposition rates were observed with 7% reduction in the amount of methionine + cystine supplementation with 500 g ton-1 Betaine. For Methionine-MHA the same was observed with 7% reduction methionine + cystine and supplementation of 1000 g ton-1. The fat deposition rate was statistically higher in treatments supplemented with betaine, but abdominal fat did not differ.
44

Utilização de betaína em substituição parcial de diferentes fontes de metionina na dieta de frangos de corte

Silva, Leandro da 28 August 2014 (has links)
A betaína vem sendo utilizada como uma fonte poupadora de metionina na dieta de frangos de corte, tendo em vista o seu menor custo, o que reduz o custo final da dieta. Outro fator de interesse na utilização da betaína é sua função osmoprotetora, que auxilia na regulação do funcionamento celular, principalmente em períodos de estresse. Foram estudadas neste trabalho duas fontes de metionina (DL-Metionina e MHA-Metionina) em diferentes níveis de metionina+cistina, e dois percentuais de inclusão de betaína na dieta, em diferentes fases de criação. No período de 1 a 7 e de 8 a 21 dias, as aves que receberam dietas com níveis reduzidos de metionina+cistina sem a suplementação com betaína apresentaram um desempenho inferior. Quando as dietas deficientes foram suplementadas, o desempenho equiparou-se aos tratamentos positivos. Não houve diferença quanto às fontes de metionina. No período de 22 a 42 dias, a matéria seca da carcaça e os rendimentos de carcaça, peito, perna, gordura abdominal e asa não diferiram. As fontes de metionina diferiram significativamente para as variáveis consumo de ração, taxa de deposição de proteína e peso relativo do fígado. O ganho de peso apresentou resultado satisfatório quanto à utilização de betaína, sendo que a redução de 7% com suplementação apresentou desempenho igual ao controle. Quando utilizada DL-Metionina, maiores taxas de deposição de proteína foram observadas com 7% de redução da quantidade de metionina+cistina com suplementação de 500 g ton-1 de betaína. Para MHA-Metionina, o mesmo foi observado com 7% de redução de metionina+cistina e suplementação de 1000 g ton-1 de betaína. A taxa de deposição de gordura foi estatisticamente superior nos tratamentos com suplementação de betaína, porém a gordura abdominal não diferiu. / Betaine has been used as a source of sparing methionine in the diet of broilers, once its cheaper than methionine, which reduces the final cost of diet. Another factor of interest in the use of betaine is over its osmo-protector function, that assists in the regulation of cell function, especially in stress phases. In this study two sources of methionine (DL-Methionine and Methionine-MHA) were studied at different levels of methionine + cystine, and two inclusion percentage of betaine in the diet at different raising stages. From 1 to 7 and 8 to 21 days, the birds fed diets with reduced levels of methionine and cystine without betaine supplementation underperformed. When deficient diets were supplemented performance equated to the positive treatments. There was no difference as to sources of methionine. In the 22-42 days period, dry matter of carcass and carcass yield, breast, leg, wing and abdominal fat did not differ. Methionine sources differed significantly for feed intake, protein deposition rate and relative weight of liver. Weight gain showed satisfactory result considering the use of betaine, and the 7% reduction with supplementation showed equal performance to the control. When DL-Methionine was used, higher protein deposition rates were observed with 7% reduction in the amount of methionine + cystine supplementation with 500 g ton-1 Betaine. For Methionine-MHA the same was observed with 7% reduction methionine + cystine and supplementation of 1000 g ton-1. The fat deposition rate was statistically higher in treatments supplemented with betaine, but abdominal fat did not differ.
45

The effectiveness of alfalfa, nutrient model, and vegetative filter strips in reduction of nonpoint source pollution

Sullivan, Bailey Ann January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Philip L. Barnes / Water quality in the United States needs to be improved. Currently, 42% (39% of rivers and streams, 45% of lakes and reservoirs) of monitored surface water is considered impaired, indicating that it is no longer suitable for its designated uses such as drinking, recreation, habitat, food supply, agriculture, and ground water recharge (USEPA, 2000, Carpenter et al., 1998). Nonpoint source pollution can be associated with animal manure. This project focuses on two sources of nonpoint source pollution. The first source is runoff from soils that have been enriched in nutrients (nitrogen and phosphorus) by manure application. This project evaluates how effective Alfalfa is at removal of nitrogen and phosphorus from nutrient enriched soils. It also evaluates the use of USDA’s Plant Nutrient model in association with nutrient management plans to prevent enrichment of soils. It was determined that Alfalfa is effective in reduction of nitrogen in soils; however, it was not feasible as a stand alone practice to remediate phosphorus. The use of USDA’s Plant Nutrient model indicated that Corn for silage is the most effective crop for reduction of soil phosphorus while alfalfa and the yields produced in 2004 was the most effective in reduction nitrogen. However, the model tends to underestimate soil nutrient uptake, so it is important to have soil tests conducted periodically to prevent nutrient deficiencies. The second source of nonpoint pollution discussed is runoff from animal feeding operations. This paper evaluates the effects of grass filter strips in prevention of pollution transport off of animal feeding operations. It was determined that filter strips with a ratio of runoff area to filter area of 1:2 is the minimum ratio to effectively prevent nonpoint source pollution.
46

Effect of replacing calf starter feed with lucerne leaf-meal on diet intake, rumen degradation and growth of Holstein heifer calves

Mangena, Joyce Ledile January 2015 (has links)
Thesis (MSc. Agriculture (Animal Production)) -- University of Limpopo, 2015 / A series of experiments were carried out to investigate the effect of replacing calf starter feed with lucerne leaf-meal (LLM) on diet intake, rumen degradation and growth of Holstein heifer calves. The treatments were calf starter pellets (PEL), a mixture of 65% calf starter concentrate pellets and 35% LLM (P65L35), and a mixture of 50% calf starter concentrate pellets and 50% LLM (P50L50). The first part of the study determined nutrient composition of lucerne leaf-meal (LLM), calf starter pellets and lucerne leaf-meal substituted diets. The experimental design was a completely randomised design (CRD). Lucerne leaf-meal had high protein (25% DM) and gross energy (GE) (16.2 MJ/kg DM) levels; low starch (0.2% DM) and fibre fractions. All diets had similar (P>0.05) crude protein (CP) and GE values. The concentrate diet was higher (P<0.05) in starch, ether extracts and fibre bound CP (neutral detergent insoluble crude protein). The second part of the study estimated the supply of energy and protein fractions and carbohydrate composition from LLM and the diets. A CRD was used. Lucerne leaf-meal had high energy density and protein supply with low unavailable fibre and protein contents. All the treatments had TDN above 80%. Non-fibre carbohydrate levels differed (P<0.05) across treatments. The energy fractions were similar (P>0.05) across all dietary treatments. However, Diets P65L35 and P50L50 had higher (P<0.05) soluble and non-fibre carbohydrates than PEL diet. The third part of the study determined in vitro degradation of LLM and the three dietary treatments using the ANKOM DaisyII incubator system. Lucerne leaf-meal had high in vitro dry matter (IVDMD), organic matter (IVOMD), crude protein (IVCPD) and neutral detergent fibre (IVNDFD) degradation. All diets had similar (P>0.05) IVDMD and IVOMD at 0, 4, 10 and 48 hours of incubation. Higher (P<0.05) IVNDFD, IVCPD and effective degradation (ED) were observed in Diets P65L35 and P50L50 than in Diet PEL. No differences (P>0.05) in IVNDFD and IVCPD were observed at 24 and 48 hours of incubation. The rate of degradation (‘c’) was similar (P>0.05) across all the diets. The data demonstrated that LLM diets had higher (P<0.05) degradation values than Diet PEL. vi The fourth part of the study determined the effects of replacing calf starter pellets with lucerne leaf-meal on diet intake, feed conversion ratio and growth of pre-weaned (21 to 42 days old calves) and transition (43 to 56 days old calves) Holstein heifer calves. The experimental design was a completely randomised design, with a total of 24 calves housed in individual pens. This study was divided into two experimental phases, namely, pre-weaning (Experiment 1) and transition (Experiment 2) phases. In each experiment, different calves were used. Body weights were taken weekly. The balance of ruminal nitrogen (% RNB) was predicted using Large Ruminant Nutrition System (LRNS) model. In Experiment 1 calves had free access to clean water and fed 4 litres/calf/day of unpasteurised milk. During the pre-weaning phase, differences (P<0.05) were observed in solid feed dry matter (DM), crude protein (CP), neutral detergent fibre (NDF) and starch intakes with Diet P50L50 having higher (P<0.05) intakes than Diets PEL and P65L35. Similarly, higher (P<0.05) % RNB and daily weight gains (ADG) were observed with calves on Diet P50L50. However, calves had similar (P>0.05) initial and final weights and feed conversion ratio (FCR). Calves in Experiment 2 were fed 2 litres/calf/day of unpasteurised milk. Calves were weaned at the age of 56 days. During the transition phase, calves on Diet HP50L50 had higher (P<0.05) CP intake and % RNB than those on HPEL and HP65L35 diets. However, higher (P<0.05) solid feed starch intake was observed with calves on Diet HPEL. All dietary treatments had similar (P>0.05) DM intake, initial and final live weights, ADG and FCR. The fifth part of the study predicted diet concentrations of Holstein heifer calves under specific conditions using the level 1 solution of Large Ruminant Nutrition System (LRNS) model. During the pre-weaning phase, P65L35 and P50L50 diets indicated higher (P<0.05) energy density values than Diet PEL. However, all diets had similar (P>0.05) metabolisable energy levels. No differences (P>0.05) in net energy for maintenance (NEm) and gain (NEg) during the transition phase were observed. However, Diet HPEL had higher (P<0.05) apparent TDN and ME levels compared to other dietary treatments. Diets P65L35 and P50L50 had higher (P<0.05) protein, energy density and degradation values than Diet PEL. It is concluded LLM inclusions in the calf diet improved Holstein heifer calves’ performance. / Agricultural Research Council (ARC)
47

Performance of elite cowpea (vigna unguiculata) genotypes at Mankweng and Bela-Bela, Limpopo Province

Sekgobela, Molebjane Marry January 2019 (has links)
Thesis (M. Sc. Agriculture (Agronomy)) -- University of Limpopo, 2019 / Cowpea (Vigna unguiculata) is a multi-purpose crop as it can be used for human consumption and livestock feeding. Cowpea serves as one of the cheapest sources of vegetable protein as the dry grain contains 25-30% protein. Its ability to tolerate drought and fix atmospheric nitrogen makes it suitable for marginal areas with low rainfall and poor soil fertility. However, low cowpea yields are common in Limpopo province due to shortage of improved varieties and lack of good seed for planting. The objectives of the present study were to determine growth, yield components and grain yield of elite cowpea genotypes across two locations and seasons, and to determine grain yield and yield components stability of the elite cowpea genotypes across the environments. The experiments were conducted at the University of Limpopo Experimental farm (Syferkuil) in Mankweng and Towoomba Research Station located in Bela-Bela, Limpopo Province during 2015/16 and 2016/17 growing seasons. The trials were carried out in a randomized complete block design (RCBD) consisting of three replications. Ten elite cowpea breeding lines (L1-L10) and a control check Bechuana White (BW) were planted at inter-row and intra-row spacings of 1 m and 0.3 m, respectively, in two rows of 6 m length. Round-up (isopropylamine salt of glyphosate) and Dual (S-metalachlor) at the rate of 3 L/ha and 0.5 L/ha, respectively, were used to control weeds at planting. Insecticide Karate (lambda-cyhalothrin) and Aphox (pirimicarb) at the rate of 1 L/ha and 500 g/ha were applied to control aphids, pod borers and other insects. Initial soil sampling was done at the depth of 0-20 cm to determine soil pH, organic matter, nitrate, ammonium, phosphorus and soil particle size. Agronomic data collected included number days to 50% flowering, number of days to 90% maturity, canopy width, plant height, peduncle length, number of pods per plant, pod length, hundred seed weight, fodder and grain yield. The collected data were subjected to analysis of variance using SAS software to determine the performance of the cowpea genotypes across the two locations and seasons. Means showing significant differences were separated using Duncan Multiple Range Test at the probability level of 5%. Data for number of days to 90% maturity, grain and fodder yields were further subjected to stability analysis through GGE biplot using Genstat software application. The results showed statistical differences for most of the studied traits as affected by genotype, location, seasonal effects and their interactions. Among the genotypes, average number of days to 50% flowering ranged from 53 to 60 days, while number of days to 90% maturity ranged from 89 to 96 days, with line L9 being the earliest to flower and mature. Tall plants were given by Line L5 (48.94 cm), followed by L7 (48.72 cm) and L10 (48.35 cm). Breeding line L7 recorded long peduncles with a mean of 36.37 cm. Number of pods per plant had a range of 16.00 to 25.52, while pod length varied from 14.46 to 17.63 cm, with line L7 having the highest number of pods per plant with long pods. Line L3 produced least number of pods per plant and shorter pods. Local check BW produced more number of seeds per pod as compared to all the breeding lines with a mean of 12.89 seeds/pod. One hundred seed weight varied from 15.67 g to 22.70 g among the genotypes. Grain yield among the genotypes ranged from 1441.20 to 2595.20 kg/ha with the best yielder being line L7, which was followed by line L2 (1928.00 kg/ha), L10 (1891.70 kg/ha) and Local variety BW (1858.70 kg/ha). The least grain yield was observed for line L8. Among the locations, Towoomba had significantly higher grain yield than Syferkuil with mean values of 1604.20 and 1982.20 kg/ha respectively. Significantly higher grain yield was recorded in 2016/17 season with a mean value of 1854.80 kg/ha than 2015/16 season (1732.30 kg/ha). Fodder yield ranged from 1934.20 to 3611.00 kg/ha, with line L3 being the highest yielder and it was followed by line L10 with an average of 3022.00 kg/ha. Local check BW produced the least fodder yields. The GGE biplot showed that lines L2, L9 and L4 matured earlier than all other lines including local variety BW and were stable across locations and seasons in terms of maturity. The biplot identified breeding lines L7, L2, L10 and Local check BW as the highest grain yielders but only line L7 and L2 were stable across the two locations and seasons. Lines L4, L10, L3, and L2 were the highest fodder yielders but only line L2 was stable across locations and seasons. Therefore, breeding lines L7 and L2 are recommended for both grain and fodder yield in both locations. Key words: cowpea, elite, breeding line, location, seasons, grain yield and stability.
48

Rinderfütterung

Alert, Hans-Joachim, Fröhlich, Brigitte, Steinhöfel, Olaf, Hiendl, Johannes, Südekum, Karl-Heinz, Zeyner, Annette, Gabel, Martin, Losand, Bernd, Pribe, Reinhard, Weber, Udo, Voigt, Jürgen 17 August 2011 (has links)
In Fütterungs- und Verdauungsversuchen mit Hammeln und Milchkühen wurden die Futterwerteigenschaften von Nebenprodukten aus modernen Verfahren wie der Zucker-Bioethanol- und Rapsmethylesterproduktion beurteilt. Durch die Fütterung von Milchkühen im Hochleistungsbereich mit 5,2 kg TM Roggenpressschlempe je Kuh und Tag wurde der Sojaextraktionsschrotverbrauch um 50 % gesenkt. Die im Hammelversuch ermittelten NEL-Gehalte für Roggenpressschlempe liegen zwischen 5,3 bis 5,5 MJ NEL je kg TM. In Verdauungsversuchen mit Milchkühen ergab sich für Lipicafett ein NEL-Gehalt von 18,4 MJ NEL/kg. Der Einsatz von 300 g Rohglyzerin je Kuh und Tag führte zu einer geringfügigen Erhöhung der Futteraufnahme von 0,4 kg TM je Kuh und Tag. Nach der Pansenbeutelmethode ermittelt, besitzt Roggenpressschlempe einen UDP-Anteil von 43 % und Weizentrockenschlempe von 25 %. Für Sojaextraktionsschrot, Rapsextraktionsschrot und Rapskuchen wurden nach dieser Methode UDP-Anteile von 39 %, 41 % bzw. 19 % ermittelt.
49

Proteinabbau einheimischer Futtermittel im Pansen

Alert, Hans-Joachim 24 July 2013 (has links)
Mit Hilfe der Pansen-Beutel-Methode wurde an drei trockenstehenden Kühen der intraruminale Rohproteinabbau von Futtermitteln ermittelt. Daraus wurden folgende UDP-Gehalte (k = 5 %/h) abgeleitet: Sojaextraktionsschrot: 30 %, Rapsextraktionsschrot: 33 %, Rapskuchen: 15 %, Roggenpressschlempe: 43 %, Weizen/Gerste-Trockenschlempe: 25 %, Ackerbohnen: 22-26 %, Körnerfuttererbsen: 20-24 %, Blaue Lupinen: 27-35 %, Leguminosen-Gras-Gemenge: 18-35 %. Bei Körnermaisschrot (trocken bzw. feucht konserviert) wurde der intraruminale Stärkeabbau bestimmt: trocken 42 % Abbau, feucht 18 % Abbau. Außerdem wurde an vier hochleistenden Kühen die Wirkung von Einzelfuttermitteln im Rahmen von Mischrationen auf die Pansenfermentation untersucht (pH-Wert, NH 3 -Gehalt, Gehalt an FFS im Pansensaft). Trotz des höheren intraruminalen Stärkeabbaus führte Feuchtkornmais zu keinem erhöhten Acidoserisiko (etwa gleicher Pansen-pH-Wert-Verlauf wie bei Trockenmais). Anhand der NH 3 -Gehalte im Pansensaft wurde ein verringerter Rohproteinabbau bei Einsatz des pansengeschützten Sojaextraxtionsschrots Soypass 50 nachgewiesen. Durch mikronisierte Rapssaat in der TMR konnte der Rohfettgehalt in der Rationstrockenmasse auf > 6 % erhöht werden, ohne dass die Pansenfermentation nachteilig beeinflusst wurde. Die Broschüre fasst alle Untersuchungsergebnisse zusammen.
50

Advanced embedded systems and sensor networks for animal environment monitoring

Darr, Matthew J. 10 December 2007 (has links)
No description available.

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