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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.
361

Fitase e fontes minerais para frangos de corte / Phytase and mineral sources to broiler chickens

Serafini, Natália Chaves January 2018 (has links)
Um estudo foi realizado para avaliar os efeitos da suplementação de uma fitase e duas fontes de Zinco (Zn), Cobre (Cu) e Manganês (Mn) sobre o desempenho produtivo e a digestibilidade de nutrientes em frangos de corte. Um total de 528 pintos da linhagem Cobb 500, machos com um dia (d) de idade foram distribuídos em 4 tratamentos com 12 repetições de 11 aves cada. Um arranjo fatorial 2 x 2 foi utilizado, sendo duas suplementações de fitase (com ou sem) e duas fontes minerais (inorgânica ou orgânica). A suplementação de fitase foi de 500 unidades de fitase (FTU)/kg, enquanto Zn-Cu-Mn foram suplementados em concentrações de 32-30-32 ou 100-120-100 ppm para as formas orgânica e inorgânica, respectivamente. Foi utilizado um programa alimentar de duas fases: inicial (1 a 12 d) e crescimento (12 a 25 d). As dietas foram formuladas de forma a atender as exigências nutricionais dos animais de acordo com a idade, exceto para Fósforo (P) disponível (Pd) e Cálcio (Ca), que tiveram níveis reduzidos (0,32% e 0,77 % na dieta inicial e 0,23% e 0,71 % na dieta crescimento para Pd e Ca, respectivamente). Os níveis de metionina nas dietas foram reduzidos conforme a adição de minerais orgânicos, que tinham como agente quelante metionina hidróxi-análoga (HMTBA). As tíbias das aves foram coletadas aos 12 e aos 25 dias de idade para determinação do teor de cinzas, Ca e P Aos 25 dias, também, foi coletado conteúdo ileal para determinação da digestibilidade ileal aparente da matéria seca (MS), Ca e P. A suplementação de fitase aumentou o ganho de peso (GP) e a conversão alimentar (CA) dos frangos dos 12 aos 25 dias e também no período acumulado (1 a 25 d). Foi observada interação entre fontes minerais e as fitases para digestibilidade de MS e P (P<0,05). A digestibilidade ileal da matéria seca foi maior nos frangos alimentados com dietas suplementadas com fitase, e também naqueles que receberam fontes inorgânicas de Zn-Cu-Mn. Os frangos que receberam dietas com fitase tiveram melhores coeficientes de digestibilidade de Ca e P (P<0,05). A fonte orgânica de microminerais resultou em maior o conteúdo de tíbia em percentual aos 12 dias. A suplementação de 500 FTU/kg de fitase nas dietas à base de milho e soja também levou a um aumento no conteúdo de cinzas das tíbias aos 12 e 25 dias, mas não houveram diferenças entre o conteúdo de Ca e P entre os animais alimentados com e sem fitase. Conclui-se que a suplementação de fitase melhora o desempenho produtivo, digestibilidade ileal de Ca e P e a mineralização óssea, e que concentrações mais baixas de minerais, através do uso de fontes orgânicas, podem ser utilizadas sem prejuízos ao desempenho animal. / A study was conducted to evaluate the effects of dietary supplementation of phytase and mineral sources of zinc (Zn), copper (Cu) and manganese (Mn) on growth performance and nutrient digestibility of broiler chickens. A total of 528 Cobb x Cobb 500 male chicks were distributed into 4 treatments with 12 replicates of 11 birds each. A 2 x 2 factorial arrangement was used with two enzyme supplementation (with or without) and two mineral sources (inorganic or organic). Phytase supplementation were 500 phytase units (FTU)/kg whereas Zn-Cu-Mn were supplemented in a concentration of 32-30-32 or 100-120-100 ppm in organic and inorganic forms, respectively. A two-phase feeding program was used, from 1 to 12 (starter) and from 12 to 25 d (grower). Diets were formulated to meet bird’s nutritional requirements according to age, except for Available Phosphorus (Av.P) and Calcium (Ca), that were formulated at 0,32% and 0,77% in starter and 0,23% and 0,71% in grower, to Av P and Ca, respectively. Methionine levels were reduced according to organic minerals supplementation, that had hydroxy-analogue methionine (HMTBA) as the chelating agent. Tibiae were collected at 12 and 25 d to measure ash, Ca and P content Also, at 25 d, ileal contents were collected to determine apparent ileal digestibility of dry matter (DM), Ca and P. Body weight gain (BWG) and feed conversion ratio (FCR) was higher with phytase supplementation from 12 to 25 d and 1 to 25 d. Dry matter (DM) digestibility was higher in animals fed diets with phytase and also in those receiving inorganic minerals. Ca and P digestibility were improved by phytase. Interactions between mineral sources and enzyme were observed to DM and P digestibility. Treatment consisting of inorganic minerals and phytase was associated with higher values of P and DM digestibility. Organic mineral source improved ash content in percentage at 12 d. Supplementing phytase to the diets led to an increase in the percentage of ash content at 12 and 25 d, but there were no statistical differences in Ca and P content between animals receiving diets with or without the enzyme. In conclusion, phytase has benefitial impacts on performance, digestibility and bone mineralisation, and lower concentrations of minerals, with organic source, can be supplied without losses to animal performance.
362

EFFECT OF BEDDING TYPE AND SOIL INCORPORATION ON NITROGEN MINERALIZATION RATE OF BROILER LITTER AMENDED SOILS

Fitzgerald, Lydia A. 01 January 2019 (has links)
Broiler litter (BL) is a high value manure available to Kentucky crop producers to utilize as a fertilizer. The rate of BL application, timing of application, and method of application are all important factors to take into account when utilizing BL. A laboratory incubation was conducted to observe nitrogen (N) mineralization rates of BL amended soils over time under different conditions. Different application methods, application rates, watering frequencies, and bedding materials were used to determine their influence on N mineralization. Broiler litter applied on the soil surface, at lower rates, at lower watering frequency resulted in lower mineralization rates than BL that was incorporated, at higher rates and higher watering frequency. The rice hull bedding BL treatments had a significantly higher initial amount of NH4+-N than the wood-based bedding materials. The increased NH4+-N content produced a lower pH due to higher rates of nitrification. The difference in NH4+-N resulted in the rice hull BL treatments containing more inorganic N throughout the incubation. The wood-based BL contained significantly more carbon (C), zinc (Zn), and potassium (K). The results collected will help improve current nutrient recommendations and provide information that will help utilize BL more efficiently and economically.
363

MICROALGAE AND ZINC SOURCE SUPPLEMENTATION OF BROILER BREEDER DIETS AFFECTS BROILER BREEDER SKELETAL DEVELOPMENT AND REPRODUCTION WITH TRANSGENERATIONAL IMPACTS ON OFFSPRING PERFORMANCE AND SKELETAL CHARACTERISTICS

Paul, Marquisha A. 01 January 2019 (has links)
Leg problems and disorders are of major concern for the poultry industry and animal welfare. Previous studies suggest that it may be possible to improve skeletal characteristics through nutrition. Omega-3 fatty acids, including Docosahexaenoic acid (DHA), are essential nutrients and are known to play an important role in bone tissue development. FORPLUS™ (Alltech, Inc.) is an unextracted, whole-cell microalgae (Aurantiochytrium limacinum CCAP 4087/2) that contains 64% fat and 16% DHA. Zinc (Zn) is a trace element and essential nutrient for growth and skeletal development. Bioplex® Zn (Alltech, Inc.) is a Zn proteinate that has been shown to be more bioavailable to broiler chickens compared to inorganic sources of Zn. One objective of this research was to investigate the effects of 2 dietary levels of FORPLUS™ (0% vs. 2%) and 2 dietary Zn sources (ZnO vs. Bioplex® Zn) on skeletal characteristics and reproduction of broiler breeders. Breeders were maintained on these diets throughout the entire pullet and layer phases. Subsequent studies were conducted to evaluate the effect of breeder diet and offspring dietary Zn sources (ZnO vs. Bioplex® Zn) and microalgae supplementation (0% vs. 1%) on offspring performance and skeletal characteristics. During the broiler breeder pullet phase, dietary supplementation of 2% FORPLUS™ increased (P < 0.05) femur ash content and length. Pullet uniformity was in increased (P < 0.05) by Bioplex® Zn vs ZnO when microalgae was not included in the diet. Hen day production (HDP) was increased (P < 0.05) by ZnO vs. Bioplex® Zn supplementation during post-peak lay. During post-peak lay, hatchability and hatch of fertile eggs were improved (P < 0.05) by dietary supplementation of 2% FORPLUS™ or Bioplex® Zn in breeder diets, however egg weight, egg yolk weight, offspring hatch weight, and offspring body weight gain (BWG) significantly were decreased (P < 0.05) by 2% FORPLUS™. Bioplex® Zn in breeder diets increased (P < 0.05) growth plate zone heights, bone-specific alkaline phosphatase enzyme activity, and dimensions of offspring bones at hatch. At 3 weeks of age, offspring from breeders fed Bioplex® Zn during peak-lay had greater (P < 0.05) Zn content in tibia ash and bone dimensions, while offspring from breeders fed 2% FORPLUS™ vs. 0% FORPLUS™ had longer (P < 0.05) femurs. No interaction effect of breeder diet and offspring diet on early performance was observed. Offspring fed diets containing Bioplex® Zn vs. ZnO had greater (P < 0.05) body weight (BW) and tibia dimensions at 3 wk of age. Offspring fed diets containing 1% FORPLUS™ had decreased feed conversion (feed intake: BWG), but no main effects were observed on skeletal characteristics. Overall, dietary microalgae supplementation in broiler breeder diets improved early bone development in broiler breeders, early bone development in broiler breeder offspring, and hatchability of offspring during post-peak lay, while Bioplex® Zn supplementation in broiler breeder diets improved broiler breeder pullet uniformity, offspring hatchability during post-peak lay, embryonic skeletal development of offspring, and offspring bone quality. Bioplex® Zn in offspring diets also improved offspring early growth performance and leg bone morphology.
364

Economic and marketing analysis of smallholder broiler production in Mopani District of Limpopo Province, South Africa

Machethe, Tanya Ashley January 2016 (has links)
Thesis (MSc. (Agricultural Economics)) -- University of Limpopo, 2016 / The broiler industry in South Africa consists of both small-scale and commercial poultry farmers. It provides the cheapest source of protein, absorbs labour and contributes massively to the agricultural sector. Broiler industry absorbs labour from the labour market, both skilled and unskilled; therefore it is a good source of employment. The specific objectives of the study included determining factors influencing productivity among smallholder broiler producers in Mopani District using Stochastic Frontier Production Function and technical efficiency analysis. The profitability of smallholder broiler production in the study area was also estimated using the Gross Margin Analysis. Furthermore, determinants of market participation among smallholder broiler producers in the study area were analysed using the Logit model. The Stochastic Frontier Production Function results revealed a positive relationship between the productivity of the farmers in their broiler production and labour, feeds, stock size and vaccines. The results also showed that feeds was significant at 1% while stock size was significant at 10% level. The technical efficiency results indicated that smallholder broiler farmers in Mopani District could save an average of 23.4 % in production costs and realize a maximum cost saving of 95.8% in production costs. The Gross Margin Analysis revealed that the cost of feeds were the highest incurred, taking up 70.61% of the total costs of production and the second highest being cost of stock comprising of 15.11% of the total production costs. The Logit results on the determinants of market participation showed that household size, income received per month, experience, land size, access to market information, distance to the market, profitability and land ownership are statistically significant in determining participation in the market. Based on the findings from the study, it is recommended that linkages between the formal markets and the smallholder farmers be established for farmers not participating in the market. Farmers who making profit and have more experience in broiler production should be provided with a platform to grow into commercial farming. This could be through subsidies or provision of other incentives that are key to enhancing expansion, such as land and funds.
365

Effect of day of hatch inoculation with Enterobacteriaceae on inflammation and enteric permeability in broilers

Chasser, Kaylin M. 04 October 2021 (has links)
No description available.
366

Effects of stocking density, genotype and sex on the growth performance and carcass characteristics of Ross and Cobb broilers chickens

Siaga, Rudzani 05 1900 (has links)
MSCAGR (Animal Science) / Department of Animal Science / See the attached abstract below
367

FACTORS AFFECTING AMINO ACID DIGESTIBILITY IN MONOGASTRIC ANIMALS

Chansol Park (8795714) 06 May 2020 (has links)
The objective of the experiments conducted for this dissertation was to determine the standardized ileal digestibility (SID) of amino acids (AA) in a variety of feed ingredients for broiler chickens and pigs. The effects of casein in experimental diets on the SID of AA in corn distillers’ dried grains with solubles (DDGS) fed to pigs were evaluated. The SID of AA in feed ingredients, which include full-fat soybean (FFSB), two soybean meals (SBM), peanut flour (PNF), full-fat canola seeds (FFCS), canola meal (CM), canola expellers (CE), hydrolyzed feather meal (HFM), flash dried poultry protein (FDPP), poultry meal (PM), and meat and bone meal (MBM), were compared in broiler chickens and pigs. One of the studies determined the ileal digestibility of AA in casein by regression analysis and investigated the effects of 60 g/kg casein in experimental diets on the SID of AA in DDGS. The ileal digestibility of AA in casein were close to 100%, ranging from 95.5% (SE = 9.10) for Cys to 103.1% (SE = 4.40) for Arg. In addition, the SID of Lys and Phe in DDGS determined by pigs fed the diet containing DDGS and casein were greater (<i>P</i> < 0.05) than the values determined by pigs fed the diet containing DDGS without casein. Based on the results of this experiment, two additional experiments were conducted to determine the effects of graded concentrations of casein from 55 to 165 g/kg in experimental diets on the SID of AA in DDGS and to determine the effects of dietary DDGS concentrations (i.e., 155.6 or 466.8 g/kg) and addition of casein in experimental diets on the SID of AA in DDGS. The SID of indispensable AA, except for Arg and Lys, linearly decreased (<i>P</i> < 0.05) as the concentration of casein in experimental diets increased. Moreover, pigs fed the diets containing 155.6 g/kg DDGS had less (<i>P</i> < 0.05) SID of indispensable AA, except for Trp, in DDGS than those fed the diets containing 466.8 g/kg DDGS regardless of the addition of casein in experimental diets. Therefore, it may be concluded that the addition of casein improves the SID of AA in DDGS, but reduced DDGS concentration in experimental diets decreases the SID of AA in DDGS. In one pair of experiments conducted to compare the SID of AA in FFSB, SBM containing 430 g/kg crude protein, SBM containing 470 g/kg crude protein, and PNF between broiler chickens and pigs, the SID of AA, except for Trp, Ala, and Glu, in test ingredients for pigs were greater (<i>P</i> < 0.05) than the values for broiler chickens. In addition, in both broiler chickens and pigs, the SID of Ile, Leu, and Val in FFSB were less (<i>P</i> < 0.05) than in the other test ingredients. In another pair of experiments conducted to compare the SID of AA in FFCS, CM, and CE between broiler chickens and pigs, interactions (<i>P</i> < 0.05) between experimental diets and species were observed in the SID of AA, except for Lys, Gly, Pro, and Ser. The SID of AA in FFCS for broiler chickens were greater (<i>P</i> < 0.05) than pigs; however, there was no difference in the SID of AA in CM or CE between broiler chickens and pigs. The objective of a third pair of experiments was to compare the SID of AA in HFM, FDPP, PM, and MBM fed to broiler chickens and pigs. There were interactions (<i>P</i> < 0.05) between experimental diets and species in the SID of His, Thr, Trp, and Val. In broiler chickens, the SID of His, Thr, and Trp in FDPP and PM were greater (<i>P</i> < 0.05) than in HFM but were less (<i>P</i> < 0.05) than MBM; however, difference in SID of His, Thr, and Trp among FDPP, PM, and MBM was not observed in pigs. Based on the results of three pairs of studies, it was revealed that differences in SID of AA in common feed ingredients for both broiler chickens and pigs were affected by species. Therefore, it may be concluded that the effects of feed ingredient-specific factors on the SID of AA are different between broiler chickens and pigs.
368

Efffects of various fertiliser materials on growth, yield and nutritional quality of three tomato varieties

Mahlatji, Maphotle Baatseba January 2019 (has links)
Thesis (M.Sc. (Horticulture)) -- University of Limpopo, 2019 / Tomato (Solanum lycopersicum L.) is one of the most popular and widely consumed vegetable crops all over the world. They play a vital role in human diet and good sources of vitamins and minerals. However, low soil fertility is a major challenge to vegetable crops production for growers in Africa. Soils in the arid and semi-arid regions like South Africa have little nutrient and mineral contents, which adversely affect plant growth and quality. Therefore, the objectives of the study were to determine the effects of sole and combined applications of Effective Microorganisms enriched compost, broiler manure and inorganic (NPK) fertiliser applications, on growth and yield of three tomato varieties and to assess the influence of the applied fertiliser on nutritional composition of three tomato varieties. Field experiments were conducted at Horticultural skill centre, University of Limpopo (Mankweng), and at Mphebatho farm, Apel, Limpopo province, South Africa. The experiment was laid out in a 7 x 3 split-plot design. Recommended amount of organic and inorganic fertilisers was used. The treatments were: control (without fertiliser application), NPK (2:3:4(30) at a rate of 200 N ha-1, 260 P ha-1 and 257 K ha-1, applied as N from Urea, P from superphosphate and K from potassium chloride (KCl), mineralised broiler manure (10 000 kg ha-1), ½ NPK + ½ broiler manure rates, EM enriched compost (14 m3 ha-1), ½ EM compost + ½ NPK rates, and ½ EM compost + ½ broiler manure rates. Three tomato varieties (Floradade, Roma and Moneymaker) seedlings were transplanted using standard spacing of 30 x 60 cm. Chlorophyll contents of leaves, biomass production, plant height, fruit number, stem diameter and branch number were determined after six weeks of transplanting and fortnightly thereafter. The interactions between tomato varieties and fertiliser materials with regard to plant height were not significant (P ≤ 0.05) at both sites (Apel and Mankweng). Average plant height (63.75 cm) obtained in Moneymaker grown in EM compost treatment was significantly highest at Apel, for Floradade (42.25 cm) in broiler manure treatment while that of Roma variety (39.63 cm) was found in ½ EM compost + ½ NPK treatment at 8 WAT. Similar trend was also recorded at 10 WAT. For Mankweng the significantly (P ≤ 0.05) highest average plant height at 8 WAT (66.63 cm) was obtained in Moneymaker grown in ½ broiler manure + ½ NPK treatment for Floradade (45.63 cm) obtained in broiler manure treatment, and 44.50 cm recorded for Roma in broiler manure treatment. Similar trend was also followed at 10 WAT. At vi Apel, significantly highest average number of tomato fruits at 8, 10 and 12 WAT were recorded in treatment with ½ EM + ½ NPK while the least values were found in control. Whereas at Mankweng the variation in number of tomato fruits under different fertiliser treatments were not significant. Similar, non-significant interactions (V x F) for tomato shoot nutritional composition were found in tomato grown at both sites (Apel and Mankweng) in relation to fertiliser treatments. At Apel however, comparing the fertiliser treatments, tomato grown in soil treated with ½ broiler manure + ½ NPK had the significantly highest average (3.01 %) K content while the least value (2.65 %) was obtained in the control. Similarly, significantly highest mean (44.33 mg kg-1) Zn was found in crops grown in the same treatment, but the lowest significant value (36.50 mg kg-1) was obtained in ½ EM + ½ NPK treatment. For Mn and Fe contents in tomato significantly highest mean values (150.17 mg kg-1 and 2381 mg kg-1) for Mn and Fe respectively were found in sole broiler manure treatment while the least values 114.83 mg kg-1 and 1357.6 mg kg-1 for Mn and Fe respectively were found in ½ EM + ½ NPK and sole NPK treatments respectively. It may be concluded that in tomato production, combined application of organic and inorganic sources of nutrients can be more beneficial and can be adopted by smallholder farmers with limited resources. / DAFF Zero hunger
369

Effect of bromine and iodine in drinking water on the physiological parameters of broilers

Du Toit, Jacolene 26 August 2011 (has links)
Assessment of a significant number of water samples across South Africa by Casey and Meyer over a number of years, revealed that high concentrations (30- 32 mg/L) of bromine (Br) occur naturally within groundwater in South Africa, hence a potentially hazardous chemical constituent (PHCC). Br, the only liquid non-metallic element, is ubiquitous and an abundant trace element, but it has not been conclusively shown to perform essential functions in plants, micro organisms or animals (NRC, 2005). The recommended limit (maximum limit for no risk) for Br in drinking water was set at 1 mg/L by Kempster et al. (1980); Casey and Meyer (2001) recommend the relevant safety guideline for Br to be 0.01 mg/L. The aim of this project was to establish the effect of Br and iodine (I) in drinking water on the physiological parameters of broilers. This will contribute to verifying and refining water quality guidelines. The effect of six treatments administered as sodium bromide (NaBr) and potassium iodide (KI): 0 mg Br/L and 0 mg I/L; 1 mg Br/L; 1mg Br/L and 0.7 mg I/L; 0.7 mg I/L; 3 mg Br/L; 3 mg Br/L and 0.7 mg I/L, in the drinking water of 540 mixed Ross broiler chickens was investigated. The trial ran over a 42-day growth period from Day 1 post-hatching where mortalities, water and feed intakes were recorded daily. Chickens were weighed weekly and slaughtered at 4 and 6 weeks of age. Blood samples were taken before slaughter and free T3 and T4 hormone levels were quantified. Thyroid gland, liver and kidney samples were analysed for Br and I quantity. The different treatments of Br, irrespective of I, significantly decreased water intake (P=0.0232) and feed intake (P=0.0035) over the 42 days. The overall interaction of Br and I had no significant effect on water (P=0.0928) and feed (P=0.9593) intakes thus I did have an effective ameliorating effect on Br. FCR, weight gain and mortalities were not significantly affected by Br intake. This was also found for free T3 and T4 hormone levels. Br had an overall effect on the thyroid gland (P=0.0457), liver (P=0.0025) and kidney (P=0.0032) with accumulation of the PHCC within these three organs. It was apparent that 1 and 3 mg Br/L water administered to broilers or ingestion rates of 1.59 and 4.44 mg Br/L per bird per day, over a production period of 42 days did affect the production parameters of the birds sub-clinically. Another derivation to refine the water quality guidelines was that the administration of 0.7 mg I/L water or ingestion rates of 1.1 mg I/L per bird per day did alleviate the severe detrimental effect of the high PHCC. The 3 mg Br/L guideline is thus not too restrictive. Further research exposing the animals for a longer time period (exceeding 42 days) and exposing mature animals (producing nutritional products for human consumption) to these treatments would assist in quantifying these results. / Dissertation (MSc(Agric))--University of Pretoria, 2010. / Animal and Wildlife Sciences / unrestricted
370

Development and Evaluation of Mucoadhesive Chitosan Nanoparticle-based Salmonella Vaccine for Oral Delivery in Broiler Birds

Han, Yi January 2020 (has links)
No description available.

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