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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.
31

Avaliação da eficiência térmica de materiais utilizados como sistemas de cobertura em instalações avícolas / Evaluation of the thermal efficiency of materials used as roofing systems in poultry houses

Ariane Cristina de Castro 16 January 2012 (has links)
O objetivo principal desta pesquisa foi avaliar a redução na carga térmica radiante e o nível de conforto térmico proporcionado pelo uso de diferentes materiais na cobertura, e diferentes forros por meio de modelos em escala reduzida e distorcida, com base nos índices ambientais de conforto térmico. A pesquisa foi realizada em duas etapas, sendo a primeira no mês de maio de 2010 e a segunda durante os meses de junho e julho de 2010. Na primeira etapa com o objetivo de avaliar a eficiência dos forros como elementos atenuadores da radiação solar foi realizado o estudo de dois tipos de telhas (cerâmica e fibrocimento) associadas a dois tipos diferentes de forro (Forro A, Forro B) e sem forro. Os forros foram instalados na parte interior do modelo em escala abaixo do telhado. Na segunda etapa, foram avaliados as telhas cerâmicas e fibrocimento, associadas ao Forro A, Forro B e a Manta Termorefletora C. A Manta termorefletora C foi alocada sobre a instalação com o objetivo de simular as condições de conforto térmico proporcionado pelo sombreamento sobre o telhado. Para avaliar o desempenho térmico dos diferentes materiais para cobertura foram registradas as variáveis meteorológicas (temperatura do ar, umidade relativa, temperatura de globo negro e velocidade do vento) e partir dessas variáveis foram calculados os índices ambientais de conforto térmico (entalpia, índice de temperatura de globo e umidade e carga térmica radiante). Foram também registradas as variações de temperatura superficiais das telhas e dos forros para a identificação da variação espacial da temperatura em diferentes horários. A primeira etapa foi composta por 6 tratamentos e a segunda etapa por 5 tratamentos. A estrutura de parcelas para as duas etapas foi o delineamento em blocos ao acaso. A análise estatística foi realizada para diferentes horários por meio da análise da variância e do teste de Tukey para a comparação múltipla das médias, visando diferenciar os tratamentos. Os resultados permitiram concluir que: dentre os tratamentos avaliados houve diferenças estatísticas entre os materiais utilizados na cobertura, e nos respectivos forros. O material de forro B foi que apresentou as maiores reduções na CTR, e nos valores de ITGU. O mapeamento térmico da temperatura de superfície dos telhados evidenciou que as menores temperaturas foram encontradas nos telhados de fibrocimento pintados de branco. E as maiores temperaturas superficiais nas telhas de cerâmica, sem pintura. O uso do sombremento de telhados em modelos em escala reduzida e distorcida não promoveu melhoria nas condições térmicas do ambiente avaliado. / The main objective of this research was to evaluate the reduction in radiant thermal load (RTL) and the level of thermal comfort provided by the use of different roofs and lining materials, through reduced and distorted scale models based on environmental indexes of thermal comfort. The research was conducted in two phases, the first in May of 2010 and the second from June to July of 2010. The first phase aimed to evaluate the efficiency of lining as an element to attenuate solar radiation. Two types of tiles (ceramic and fibrous cement) were studied associated with two different liners (linings A and B). The liners were installed under the roof inside of the scale model. The second phase evaluated ceramic and fibrous cement tiles associated with liners A and B and with the thermal reflective blanket C, which was allocated over the installation in order to simulate the thermal comfort provided by the roof shading. To the evaluation of the thermal performance of the different roofing materials, meteorological variables were recorded (air and black globe temperatures, relative humidity and wind velocity), to the posterior calculation of thermal comfort environmental indexes (enthalpy, black globe temperature and humidity index GTHI and radiant thermal load). Variations on the surface temperature of tiles and liners were also recorded to identify the spatial variation of temperature at different times of the day. The first phase consisted of 6 treatments and the second consisted of 5 treatments. A completely randomized experimental design was adopted in the two phases. The statistical analysis was performed for the different times by analysis of variance and Tukeys test of multiple comparison of means, aiming to observe differences among the treatments. The results showed a statistical difference between the materials used for roofing and lining. Liner B presented the highest reductions of RTL and GTHI values. The thermal mapping of the surface temperature of tiles showed that the lowest temperature were found in fibrous cement roofs white painted, while the highest surface temperatures were found in the unpainted ceramic tiles. The use of shading roof in reduced and distorted scale models did not improve the thermal conditions of the evaluated environment.
32

Efeitos da piperina em frangos de corte (Gallus gallus) com intoxica??o experimental por aflatoxinas. / Effects of the piperine in broiler chickens (Gallus gallus) with experimental aflatoxins intoxication.

Cardoso, Ver?nica da Silva 05 March 2007 (has links)
Made available in DSpace on 2016-04-28T20:17:25Z (GMT). No. of bitstreams: 1 2007-Veronica da Silva Cardoso.pdf: 1668808 bytes, checksum: 8c509f980dcd2dcbfda2f388e9cd9a42 (MD5) Previous issue date: 2007-03-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The aim of the present study was to analyze the interference of the administration of piperine in broiler chickens with prolonged aflatoxins intoxication. The experiment was accomplished in two phases: (i) the chickens were separate in four groups test (n=15 broilers / I group), that received different piperine concentrations (1.12, 2.25 and 4.5mg/kg orally/14 days), and a control group, that was only inoculated with the vehicle; (ii) chickens were separate in 3 groups (n=15 broilers/group), a group that received only piperine (2.25 mg/kg), a group that received aflatoxins only (2.0 mg/kg) and another group that received an association of piperine (2.25 mg/kg) and aflatoxins (2.0 mg/kg), all orally / 14 days. At the end of the experiment, the chickens were slaughted and productivity indexes, hematological parameters and histopathological parameters of every digesting tract were evaluated. The results obtained in the first phase showed that the piperine, in the employed doses, didn't interfere in the productivity indexes nor in the result of the values of hematocrit, hemoglobin concentration, fibrinogen and erythrocyte counts, except for the highest doses of piperine, which were capable to promote an increase in the total counting of the white blood cells. The dose of 2.25 piperine mg/kg was not toxic or had and the histopathological lesions observed were dose-dependent. In the second phase of the experiment, it was observed that the productivity indexes in the group that received the association piperine and aflatoxins obtained better performing comparatively with those that just received aflatoxins. The piperine in the concentration of 2.25 mg/kg reduced in a significant way the immunosuppresor activity and the histopathological lesions caused by the aflatoxins. It can be suggested that piperine interferes in a positive way, reducing the toxic effects of the aflatoxins intoxication in broiler chickens. / Este trabalho teve como objetivo analisar a interfer?ncia da administra??o da piperina em frangos de corte com intoxica??o prolongada por aflatoxinas. O experimento foi realizado em duas fases: (i) os frangos foram separados em quatro grupos teste (n=15 aves/ grupo), que receberam diferentes concentra??es de piperina (1,12; 2,25 e 4,5mg/kg por via oral/14 dias), e um grupo controle, que foi inoculado apenas com o ve?culo; (ii) os frangos foram separados em 3 grupos (n=15 aves/grupo), um grupo que recebeu apenas piperina (2,25 mg/kg), um grupo que recebeu apenas aflatoxinas (2,0 mg/kg) e outro grupo recebeu piperina (2,25 mg/kg) em associa??o com aflatoxinas (2,0 mg/kg), todos por via oral/ 14 dias. Ao final do experimento, os frangos foram abatidos e avaliados quanto aos ?ndices de produtividade, par?metros hematol?gicos e par?metros histopatol?gicos de todo trato digest?rio. Os resultados obtidos na primeira fase mostraram que a piperina, nas doses empregadas, n?o interferiu nos ?ndices de produtividade ou nos valores de hemat?crito, hemoglobina, fibrinog?nio e n?mero de hem?cias, com exce??o das doses mais elevadas de piperina, as quais foram capazes de promover um aumento na contagem total de leuc?citos. A dose de 2,25 mg/kg de piperina n?o foi t?xica ou imunossupressora e as les?es histopatol?gicas observadas foram dose dependente. Na segunda fase do experimento, observou-se que de acordo com os ?ndices de produtividade, o grupo que recebeu piperina em associa??o com aflatoxinas obteve melhor desempenho comparativamente com aqueles que receberam apenas aflatoxinas. A piperina na concentra??o de 2,25 mg/kg reduziu de forma significativa ? imunossupress?o e as les?es histopatol?gicas causada pelas aflatoxinas. Desta forma, pode-se sugerir que a piperina interfere de forma positiva na intoxica??o de frangos de corte por aflatoxinas, diminuindo seus efeitos t?xicos.
33

Efeitos da metionina e da arginina sobre a resposta imune e o desempenho de frangos de corte

Rubin, Lauricio Librelotto January 2007 (has links)
Nosso conhecimento de nutrição em avicultura é relativamente maduro, incluindo uma completa lista de exigência de nutrientes, o estabelecimento dos níveis mínimos de cada nutriente necessários para uma máxima produtividade e os níveis e a biodisponibilidade desses nutrientes, contidos nas matérias-primas utilizadas no fábrico das rações. No entanto, não sabemos se os níveis adequados de nutrientes para um ótimo crescimento, em animais saudáveis, são adequados para uma ótima resposta imune ou imunocompetência durante um desafio infeccioso. Um dos mecanismos através dos quais a nutrição interfere na imunidade é a regulação pela disponibilidade de substrato, sendo estabelecido pelo fornecimento de nutrientes necessários para uma resposta imune. Um dos exemplos implicados nesse grupo são os aminoácidos e, dentre esses, a metionina e a arginina. A metionina é importante para a síntese protéica, para a formação de glutationa e poliaminas e é a principal fonte doadora de grupos metila para a formação do DNA. A arginina é importante para a produção de óxido nítrico nos macrófagos. O óxido nítrico tem ação bactericida, cumprindo importante papel na atividade citotóxica celular. Este trabalho teve como objetivo verificar se níveis de metionina e arginina usualmente utilizados na indústria avícola influenciam a resposta imune de frangos de corte submetidos a estímulos imunológicos. O primeiro experimento avaliou a influência da metionia, expressa em aminoácidos sulfurados totais (AAS). Na fase inicial de criação (1 a 21 dias) foram utilizados 0,72; 0,82 e 0,92% de AAS e na fase final (22 a 42 dias) 0,65; 0,75 e 0,85% de AAS. Os estímulos empregados nesse experimento foram as vacinas comumente utilizadas na indústria avícola, micobacterium avium inativado e tuberculina aviária. Como resultado tivemos que os níveis de AAS testados não influenciaram a resposta imune. Porém, as vacinas realizadas prejudicaram o desempenho dos frangos até os 21 dias de idade. De 1 a 42 dias de criação, houve uma interação entre os estímulos e os níveis de AAS, onde o maior nível de AAS do grupo não estimulado mostrou melhor ganho de peso. O segundo experimento avaliou a influência de diferentes níveis de metionina (0,31; 0,51 e 0,66% de 1 a 21 dias e 0,29; 0,49 e 0,64% de 22 a 42 dias de criação) e arginina (1,33 e 1,83% de 1 a 21 dias - 1,14 e 1,64% de 22 a 42 dias) sobre a resposta imune e sobre o desempenho de frangos de corte. O programa de estímulos foram vacinas comumente utilizadas na indústria avícola, eritrócito de carneiro a 10%, micobacterium avium inativado e tuberculina aviária. Como resultado desse experimento tivemos que os níveis de arginina testados não influenciaram o desempenho nem a resposta imune das aves, e em relação a metionina, não houve influência sobre a resposta imune humoral, mas o nível intermediário de metionina obteve melhor resposta celular. Além disso, as vacinas realizadas no primeiro dia prejudicaram o desempenho dos frangos até os 21 dias de idade. Com base nos dois estudos é possível concluir que os níveis de metionina e arginina utilizados atualmente na nutrição de frangos de corte, podem ser adequados para atender a demanda do sistema imune. Em termos de desempenho, os níveis de metionina (AAS) utilizados na agroindústria, podem ser aumentados, aliados a um bom programa sanitário. Além disso pode-se observar que os programas de vacinação, embora necessários, certamente interferem negativamente no desempenho das aves. / Our knowledge of nutrition of poultry and livestock is relatively mature, including a very complete listing of the required nutrients, a quantitative accounting of the minimal level of each nutrient that is needed to maximize production characteristics, and the levels and bioavailabilities of the essential nutrients supplied by feedstuffs. However, it is not known if the requirement values that maximize productivity in healthy, unchallenged animals are optimal for immunocompetence and disease resistance. The regulation by substract availability (diet nutrients) is one of mechanisms trough of witch nutrition interferes on immune response. Amino acids like methionine and arginine are two examples of this. Methionine is important for protein synthesis, glutathione and polyamines production and is the principal source of metil groups to DNA formation. Arginine is important to nitric oxide production by macrophages. Nitric oxide has bactericide action, playing important role in cellular citotoxic activity. This study aim to evaluate the influence of supplementation at different methionine and arginine levels on performance and the immune response in broiler chickens immunologically stimuli. First experiment evaluated methionine (as sulfur amino acids – SAA). In initial fase (1 to 21 days) the levels tested were 0.72, 0.82 and 0.92% and final fase (22 to 42 days) the levels were 0.65, 0.75 and 0.85%. The stimuli program was constituted of vaccines routinely adopted in large-scale bird husbandry, inactivated Mycobacterium avium and avian tuberculin. As results SAA levels tested not influenced immune response. Yet, vaccines administered impaired bird performance upon the 21st day of age. In total period an interaction between immunological stimuli and SAA levels was observed, at this the greatest level of ASS in no-stimulated group showed better weight gain. The second experiment tested the influence of methionine levels (0.31, 0.51 and 0.66% in initial phase and 0.29, 0.49 and 0.64% in final phase) and arginine levels (1.33 and 1.83% in initial phase and 1.14 and 1.64% in final phase) on bird performance and immune response. The stimuli program was vaccines routinely adopted in large-scale bird husbandry, inactivated Mycobacterium avium, Sheep Red Blood Cells 10% (SRBC), and avian tuberculin. It was observed that arginine levels tested influenced neither bird performance nor immune response. To methionine, no effect was observed on humoral immune response, however the intermediate methionine level caused better immune cellular response. Moreover, the vaccines administered on the first day impaired bird performance upon the 21st day of age. Based on these two experiments results it’s possible to conclude that methionine and arginine levels here tested witch are similar of those used on current poultry nutrition could be adequate to attend immune system requirements. To performance this practical levels of methionine could be increased if a god sanity program is used. Moreover, it’s possible to see that vaccination programs are necessary but certainly interfere on bird performance in a negative way.
34

METABOLIZABLE ENERGY DETERMINATION IN BROILER CHICKENS

Dunaway, Andrew E. 01 January 2019 (has links)
Feed accounts for the highest cost associated in poultry production, with energy-containing feedstuffs being the most expensive portion of the cost of feeding. The increasing demand for poultry meat gives reason to determine accurate apparent metabolizable energy (AME) values for various feedstuff through measuring energy utilization in the birds. The adaptation length of birds fed an experimental diet may affect the determined AME value due to the diet matrix and physiochemical properties of the feedstuff. Therefore, the objective of this thesis was to evaluate a select group of energy-containing feedstuff with different diets and with factors such as coccidia challenge and exogenous enzyme supplementation that may influence the determined AME values in broiler chickens.
35

Effect of feed restriction and lysine supplementation during realimentation on productivity and carcass characteristics of Ross 308 broiler chickens.

Novele, Dionisio Justino 19 August 2010 (has links)
Thesis (M.Sc) (Agriculture)--University of Limpopo,2007. / Two experiments were carried out to evaluate the effects of feed restriction during the starter stage and lysine supplementation during realimentation on productivity and carcass characteristics of Ross 308 broiler chickens. In the first experiment, the effects of level and period of feed restriction during the starter period on subsequent productivity were evaluated. A 2 (male and female chickens) x 3 (feeding levels, ad libitum and 75% and 50% of ad libitum) x 3 (restriction periods of 5, 7 and 9 days), factorial arrangement in a Completely Randomized Design was used. The effects interactions were not included in the results because earlier analyses including all the interactions showed that they were not important. Level and period of feed restriction during the starter stage had an effect (P<0.05) on live weight of the chickens at 21 days of age. However, female and male chickens had similar live weights at 21 days of age. Chickens on 75% ad libitum feeding attained complete live weight compensation at the age of 42 days. However, chickens on 50% ad libitum feeding did not ‘catch-up’ with those on ad libitum feeding. Differences due to the period of feed restriction during the starter stage were maintained up to the age of 42 days. Male chickens had higher (P<0.05) live weights at 42 days of age. Abdominal fat pad was not affected (P>0.05) by level and period of feed restriction and sex of chickens at 42 days of age. The second experiment evaluated the effects of feed restriction during the starter stage (14 to 21 days) and levels of lysine supplementation during realimentation (21 to 42 days) on productivity and carcass characteristics of male and female chickens. Feed v restriction affected (P<0.05) live weight of chickens at the age of 21 days and males were heavier (P<0.05) than females at the same age. Chickens on 75% ad libitum feeding attained complete compensation in live weight while those on 50% ad libitum feeding did not. Lysine supplementation during realimentation had no effects (P>0.05) on live weight and carcass characteristics of the chickens at 42 days of age. Male chickens attained higher (P<0.05) live weights than female chickens at 42 days of age. / National Research Foundation
36

Effect of dietry carrot meal supplementation on productivity and carcass characteristics of arbor acre broiler chickens

Mokgope, Precious Kgomotso January 2014 (has links)
Thesis (MA. Agricultural Management (Animal Production)) -- University of Limpopo, 2014 / This study determined the effect of carrot meal supplementation on productivity and carcass characteristics of Arbor acres broiler chickens aged one to six weeks. Experiment I determined the effect of carrot meal supplementation on productivity of Arbor acre broiler chicks aged one to 21 days. Two hundred unsexed Arbor acre broiler chickens were randomly assigned to five treatments with five replicates, each replicate having ten birds. A completely randomized design was used in the first experiment. The treatments were 0 (UA0), 20 (AU20), 50 (AU50), 75 (AU75) or 100 (AU100) g of carrot meal supplementation per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged one to 21 days. Linear equations were used to determine relationships between carrot meal supplementation and productivity variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation, however, improved (P<0.05) metabolisable energy intake and nitrogen retention of the chickens. Dietary metabolisable energy intake and nitrogen retention of the chickens were optimized at different carrot meal supplementation levels of 40.5 and 53.57 g/kg DM feed, respectively. No chicken deaths were recorded. Experiment II determined the effect of carrot meal supplementation on productivity and carcass characteristics of female Arbor acre broiler chickens aged 22 to 42 days. The chickens were randomly allocated to five treatments with five replicates, each having 10 birds, in a completely randomized design. The supplementation levels were 0 (FA0), 20 (FA20), 50 (FA50), 75 (FA75), or 100 (FA100) g of carrot meal per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention of broiler chickens aged 22 to 42 days. Linear equations were used to determine relationships between carrot meal supplementation and production variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and carcass parts of female Arbor acre broiler chickens aged 22 to 42 days. Carrot meal supplementation improved (P<0.05) feed intake, feed conversion ratio, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged vi 22 to 42 days. Dietary feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention were optimized at different dietary carrot meal supplementation levels of 52.8, 63.8, 38.0, 42.0 and 44.3 g/kg DM feed, respectively. Dietary carrot meal supplementation had no effect (P>0.05) on tenderness and flavour of female Arbor acre broiler meat. Broiler chickens on diets supplemented with 20, 50 or 100 g of carrot meal per kg DM feed produced meat with better (P<0.05) juiciness values than those of meat from chickens not supplemented with dietary carrot meal and those supplemented with 75 g/kg DM feed. There was a positive relationship between carrot meal supplementation and chicken meat juiciness. It is concluded that carrot meal supplementation improved (P<0.05) metabolisable energy intake and nitrogen retention of unsexed Arbor acre broiler chickens aged one to 21 days. However, carrot meal supplementation had no effect (P>0.05) on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation improved (P<0.05) intake, feed conversion ratio, metabolisable energy and nitrogen retention of female Arbor acre broiler chickens aged 22 to 42 days. However, carrot meal supplementation did not (P>0.05) improve growth rate and live weights of the chickens.
37

Physiological and nutritional factors affecting protein digestion in broiler chickens

Rynsburger, Joni Maria 30 September 2009
A series of experiments were conducted to examine protein digestion in the young bird and the physiological changes that affect protein digestion as the bird matures. Trial one determined the effect of age on pH of the gastrointestinal tract. The results showed that the pH of the proventriculus and gizzard decreases with age suggesting that gastric acid secretion increases proportionally with age and this may impact protein digestion. Experiment two examined the effect of age on ileal amino acid (AA) digestibility of feed ingredients. AA digestibility increased from 5 to 21 d and the degree of improvement differed among ingredients and specific AA. This finding coupled with the low AA content of some ingredients demonstrates the importance of using appropriate nutrient digestibility values for young birds when formulating pre-starter and starter diets. Experiment three determined the acid binding capacity (ABC) of feed ingredients and the effect of formulating diets based on ABC on diet ABC, gastrointestinal pH and performance. The research confirmed dramatic differences in ABC among ingredients and that diets could be formulated on the basis of ingredient ABC. However, the range in diet ABC was less than predicted suggesting interactive effects among ingredients. Intestinal pH was reduced however broiler performance was not improved when diets low in ABC were fed. Experiment four examined the effect of diet acidification with HCl on diet ABC, gastrointestinal pH, ileal amino acid digestibility and broiler performance. Improvements in performance and reductions in mortality were observed when broilers were fed acidified diets. Adding acid to diets did not improve AA digestibility and therefore was not the reason for improved performance indicating an alternative mechanism of action. It is concluded that acid production by the proventriculus of young birds is low and increases with age however this does not impact protein digestion. Methods of improving performance of broiler chickens may include diet acidification however this is not the effect of remedying the low acid production by young birds. Therefore, alternative mechanisms are positively affecting broiler performance.
38

Physiological and nutritional factors affecting protein digestion in broiler chickens

Rynsburger, Joni Maria 30 September 2009 (has links)
A series of experiments were conducted to examine protein digestion in the young bird and the physiological changes that affect protein digestion as the bird matures. Trial one determined the effect of age on pH of the gastrointestinal tract. The results showed that the pH of the proventriculus and gizzard decreases with age suggesting that gastric acid secretion increases proportionally with age and this may impact protein digestion. Experiment two examined the effect of age on ileal amino acid (AA) digestibility of feed ingredients. AA digestibility increased from 5 to 21 d and the degree of improvement differed among ingredients and specific AA. This finding coupled with the low AA content of some ingredients demonstrates the importance of using appropriate nutrient digestibility values for young birds when formulating pre-starter and starter diets. Experiment three determined the acid binding capacity (ABC) of feed ingredients and the effect of formulating diets based on ABC on diet ABC, gastrointestinal pH and performance. The research confirmed dramatic differences in ABC among ingredients and that diets could be formulated on the basis of ingredient ABC. However, the range in diet ABC was less than predicted suggesting interactive effects among ingredients. Intestinal pH was reduced however broiler performance was not improved when diets low in ABC were fed. Experiment four examined the effect of diet acidification with HCl on diet ABC, gastrointestinal pH, ileal amino acid digestibility and broiler performance. Improvements in performance and reductions in mortality were observed when broilers were fed acidified diets. Adding acid to diets did not improve AA digestibility and therefore was not the reason for improved performance indicating an alternative mechanism of action. It is concluded that acid production by the proventriculus of young birds is low and increases with age however this does not impact protein digestion. Methods of improving performance of broiler chickens may include diet acidification however this is not the effect of remedying the low acid production by young birds. Therefore, alternative mechanisms are positively affecting broiler performance.
39

Fitogeninio preparato Biomin P.E.P. - 1000 įtaka paukščių lipidų apykaitai / Influence of phytogenic preparation Biomin P.E.P. - on lipid metabolism in the organism of birds

Gudiškytė, Loreta 08 June 2004 (has links)
The aim of this study was to investigate the impact of Biomin P.E.P. – 1000 on the total quantity of lipids and triglycerides in blood serum of broiler chickens, also to analyze the impact of the preparation on the dynamics of growth and meat qaulity of birds. The results of our study show taht under the influence of phytogenic preparation Biomin P.E.P. – 1000 the content of total lipids and trigycerides in the blood serum of the broiler chickens at the age of 21 days increased, respectively, by 1,93 – 4,73 g/l and 0,22 – 1,07 mmol/l as compared to the control group. At the age of 42 days it increased: lipids by 0,82 – 1,61 g/l and triglycerides by 0,3 – 0,83 mmol/l as compared to the control group. In the influensce of this preparation the weight of broiler chickens increased by 9,92 – 10,62 % as compared to the control group. The testing of meat chemical composition showed positive influence of Biomin P.E.P. – on the quality of broiler chicken meat.
40

Probiotikų, prebiotikų ir fermentų įtaka žiurkių ir viščiukų broilerių virškinimo procesams bei viščiukų broilerių produktyvumui / Effects of probiotics, prebiotics and enzymes on digestive processes of rats and broiler chickens and productivity of broiler chickens

Semaškaitė, Agila 20 October 2008 (has links)
Darbo tikslas - nustatyti probiotikų, gautų iš pieno rūgšties bakterijų kamieno Pediococcus acidilactici MA 18 5 M, prebiotikų fruktooligosacharidų ir nekrakmolinius polisacharidus skaldančių fermentų įtaką žiurkių ir viščiukų broilerių virškinimo procesams, viščiukų broilerių produktyvumui ir mėsos juslinėms savybėms. Darbo metu atlikti moksliniai eksperimentai siekiant palyginti skirtingų vienkamerinių gyvūnų – žiurkių ir viščiukų broilerių virškinimo procesų kitimą šeriant ir lesinant juos probiotikų, prebiotikų, NKP skaldančių fermentų ir jų kombinacijų priedais. Šiame darbe atlikti išsamūs moksliniai tyrimai, kurių metu pagal vienodas bandymų schemas vykdyti eksperimentai su laboratoriniais gyvūnais (žiurkėmis) ir viščiukais broileriais. Vykdyti palyginamieji tyrimai, kurie gali būti naudojami kaip modelis tiriant naujus pašarų priedus. Pirmą kartą ištirta probiotikų, prebiotikų ir NKP skaldančių fermentų įtaka žiurkių ir viščiukų broilerių aklosios žarnos chimuso bakterinių fermentų, apsprendžiančių kancerogeninių metabolitų susidarymą, aktyvumams ir viščiukų broilerių mėsos juslinėms savybėms. Be to, nustatyta šių zootechninių pašarų priedų įtaka viščiukų broilerių produktyvumui ir jų fiziologinei būklei. / The aim of the present study is to determine the effect of probiotics lactic acid bacteria, produced from strain Pediococcus acidilactici MA 18 5 M, prebiotics fructooligosaccharides and non-starch polysaccharides (NSP) hydrolyzing enzymes on digestive processes of rats and broiler chickens, productivity and sensory attributes of the meat of broiler chickens. Three studies to determine the digestive processes of two different species of monogastric animals such as rats and broiler chickens fed diets supplemented with probiotics, prebiotics and non-starch polysaccharides (NSP) hydrolyzing enzymes were performed. The studies with laboratory animals (rats) and broiler chickens were performed according to the same experimental scheme. The comparable studies, which can be used as model for analysis of new zootechnical feed additives, were performed for the first time. The effect of probiotics, prebiotics and NSP hydrolyzing enzymes on activity of caecal chymus bacterial enzymes, which might play a role in activation of procarcinogens in large intestine of rats and broiler chickens were determined for the first time. Due to production of health, safe and high quality poultry products, the effects of these zootechnical feed additives on sensory attributes of the meat of broiler chickens were determined for the first time.

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