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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

Evaluation of Particle Size Differences, Calcium Sources, and Phytases on Ph and Calcium and Phosphorus Solubility in an in Vitro Simulation of Broiler Digestion

Wladecki, Hannah Victoria 05 November 2012 (has links)
Broiler nutrition can be affected by many different factors, and diets can be made up of a wide variety of components. Feed enzymes, different Ca sources, and various ingredient particle sizes all contribute to broiler nutritional status and need to be investigated to determine their full effects on the bird. The objective of the first study was to evaluate various Ca sources and microbial phytases using an in vitro assay to simulate broiler digestion. The trial measured total Ca and P, soluble Ca and P, and pH. It involved limestone, dicalcium phosphate, highly soluble Ca (HSC), whey, and a control with no added Ca. Each diet was supplemented with 0 or 500 FTU/kg of phytase 1 or phytase 2. Diets were analyzed for total Ca and P and then were subjected to a gastric phase digestion, including the addition of HCl and pepsin, with incubation times of 5, 10, or 20 min. They were also subjected to a gastric phase and a SI phase digestion, including the addition of HCl, pepsin, NaHCO3, and pancreatin with incubation times of 5, 10, 20, or 60 min. The objective of the second study was to evaluate various particle sizes, Ca sources, and source locations using the same in vitro assay. Large, medium, and fine particle sizes, as well as limestone from 4 different locations and HSC were subjected to the same assays and conditions as in the first trial. These studies suggest that HSC is a highly soluble Ca source, phytase improves P solubility in vitro, fine particle size is more soluble than large particle size in vitro, and location from which the Ca source is obtained can affect Ca and P solubility. The in vitro assay utilized in this study is a fast and cost efficient technique for evaluating and comparing parameters of broiler diets to make recommendations for commercial poultry nutrition. / Master of Science
32

Effects of dietary Ca concentration on the performance of broiler chicks fed various sources of dietary P with and without phytase supplementation

Fritzlen, Cooper January 2021 (has links)
Two experiments were conducted to determine the effects of high dietary calcium (Ca) on broiler chicks fed low phosphorus (P) diets from either nonphytate (nPP) or phytate P (PP) with or without phytase. The response criteria that were analyzed was bird performance, tibia ash, Ca and P digestibility and duodenal P transporter mRNA abundance. Newly hatched broiler chicks were housed in raised-wire starter batteries (65.8 in2) for 16 d. Each experiment had 12 treatments were replicated 6 times using 8 chicks per cage that resulted in a total of 576 Cobb 500 chicks. Experiment 1 had a 3x2x2 factorial arrangement included 3 P treatments (0.225%nPP, 0.225 + 0.1%P from nPP and 0.225 + 0.1%PP), 2 concentrations of Ca (0.9 vs.1.7%Ca) and either (0 or 1,000 FTU of phytase). Experiment 2 also had a 3x2x2 factorial arrangement but set closer to commercial standards (0.325% nPP, 0.325 + 0.1% P from nPP and 0.325 + 0.1% P from PP), 2 concentrations of Ca (0.9 vs.1.4% Ca) with and without phytase (0 or 1,000 FTU of phytase). Body weight gain (BWG), feed intake, feed conversion and mortality were calculated over the 16d period. On 16d, all remaining chicks were euthanized, and the right tibia was analyzed for tibia ash weight (TAW) in mg/tibia and expressed as a percentage (TAP). All data were analyzed as a 3x2x2 factorial using ANOVA in JMP 14 (P ≤ 0.05). In Experiment 1, the phytase interactions were driving FI, which increased BWG (P ≤ 0.05). However, the phytase interactions did not influence bone mineralization (P ≤ 0.05). So, the diet is potentially more appetizing with phytase supplementation. Calcium x phosphorus interaction was driving bone mineralization, but not influencing BWG or FI (P ≤ 0.05). Additionally, bone mineralization was impacted when additional P was put into high Ca diets (P ≤ 0.05). Phytase upregulated P transporter mRNA abundance in normal Ca diets, but the results were muted in high Ca diets (P ≤ 0.05). Experiment 2 used more practical P and Ca conditions to validate the responses from Experiment 1 with the understanding that the potential responses would be blunted. The addition of phytase improved tibia ash when Ca and P were unbalanced (P ≤ 0.05). High concentrations of Ca lowered BWG and FI, but again the addition of phytase to the diet had a more beneficial effect (P ≤ 0.05). Diets with reduced P had an improved P and Ca digestibility and upregulation of P transporter mRNA abundance (P ≤ 0.05). Also, the addition of phytase improved both P and Ca digestibility and downregulated P transporter mRNA abundance (P ≤ 0.05). Overall, both experiments exhibited that source of P did not influence performance but did influence tibia ash. High calcium had a negative effect on performance and digestibility. However, phytase was able to ameliorate negative impacts of high calcium diets. The multiple interactions of Ca, P and phytase indicate a complex relationship among the three factors that require balancing when looking for optimal conditions commercially, especially to maximize performance and skeletal health while balancing cost and environmental considerations. / M.S. / Phosphorus and calcium have many important functions within the body including energy metabolism, cell signaling, bone development and mineralization. When deficiencies of these minerals are seen in broiler chickens a decrease in skeletal health will be one of the first visual signs, where commercially will show up as leg issues. However, meeting the dietary requirements for P and Ca is not a simple task. A considerable amount of P in poultry diets is in the form of phytate P, which is an organic form of P that is hard to digest by the bird. In most cases inorganic P must be fed to meet the broiler requirements for P because its easily absorbed by the animal. Another way to increase the utilization of these minerals is with the supplementation of phytase into the diet. Supplementing phytase allows for a decrease in the amount of inorganic P being added to the diet. The decrease of inorganic P put in the diet saves industries money and is more beneficial for the environment. The addition of phytase also increases the utilization of Ca from the diet, which is brought into consideration during the formulation of the diet. However, there is still a potential for over supplementation of Ca commercially if there are feed mixing errors or high concentrations of Ca from new feed additives. Over supplementation of Ca can lead to many issues which include reduced nutrient digestibility, reduced performance, and an influence on the effectiveness of phytase. Therefore, the effects of feeding high dietary Ca on broiler chicks fed phosphorus from either nonphytate P or phytate P sources with or without phytase were determined with a focus on bird performance, tibia ash, Ca and P digestibility and duodenal P transporter mRNA abundance. Across both experiments source of P did not influence performance but did influence tibia ash. High calcium had a negative effect on performance and digestibility. However, phytase was able to ameliorate negative impacts of high calcium diets. The multiple interactions of Ca, P and phytase indicate a complex relationship among the three factors that require balancing when looking for optimal conditions commercially, especially to maximize performance and skeletal health while balancing cost and environmental considerations.
33

Effects of increasing phytase in nursery pig diets and determining the impact of increasing lysine in lactating sows

Gourley, Kiah Marie January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Joel DeRouchey / Jason Woodworth / Two experiments using a total of 646 nursery pigs were used to determine the effects of increasing phytase on nursery pig growth performance and bone ash characteristics. Two experiments using a total of 821 sows were used to determine the impact of increasing standardized ileal digestible (SID) lysine (Lys) in lactating sows. Experiment 1 determined the available phosphorus (aP) release of Natuphos E 5,000 G phytase in nursery pigs. Increasing phytase from 0 to 1,000 FTU/kg in phosphorus deficient diets improved nursery pig performance and bone ash characteristics. Using percentage bone ash and formulated phytase concentrations, an equation was developed to predict aP release up to 1,000 FTU/kg of Natuphos E phytase. Experiment 2 was conducted to determine the effect of Superdosing Natuphos E 5,000 G phytase on nursery pig performance and bone ash characteristics. Increasing phytase in diets marginal in P improved pig performance and bone ash values. Increasing phytase in P sufficient diets improved bone ash percent and tended to improve feed efficiency. Experiments 3 and 4 determined the impacts of increasing SID Lys in primiparous and multiparous lactating sows and their litters. In Exp. 3, increasing SID Lys above 0.80% in primiparous sows decreased backfat loss, but had no effect on sow BW loss, ADFI or litter gain. Conception rate at d 30 and percentage born alive tended to improve at 0.95% SID Lys. In Exp. 4 with mixed parity sows, increasing SID Lys to 1.05% increased sow weaning BW, litter gain, and reduced weight loss in lactation. Sow backfat loss increased as SID Lys increased from 0.75 to 1.20%, however loin eye depth loss was reduced as SID Lys increased. Percentage of females bred by d 7 after weaning was improved in primiparous females with increasing SID Lys, however no difference was observed in multiparous sows.
34

INFLUENCE OF AGE AND FEEDING LENGTH ON PHYTASE EFFICACY IN BROILER CHICKENS

Olufemi Babatunde (5930525) 17 January 2019 (has links)
The objective of this thesis was to investigate the effect of age and feeding length on phytase efficacy in broiler chickens during the starter phase. Two studies were carried out to evaluate this objective.<br>Study 1 was a randomized complete block design with 4 × 5 factorial arrangements of treatments. There were four diets; a positive control (PC), negative control (NC) and two phytase supplemented diets with inclusion levels of 1,000 and 2,000 phytase units/kg. There were five age and duration of feeding groups; Three 2-d feeding lengths terminated at d 8, 14, and 22 (d 6 to 8, d 12 to 14, and d 20 to 22), a 5-d feeding length terminated at d 14 (d 9 to 14) and a 16-d feeding length terminated on d 22 (d 6 to 22). Growth performance and sample collections were collected at the end of each phase i.e. d 8, 14 and 22. There was a difference (P < 0.01) in weight gain, feed intake, and feed efficiency between birds fed the PC diets and birds fed the NC diets across all groups as birds on the NC diets had lower performance (P < 0.05) than birds on the PC diet. However, birds fed the phytase supplemented diets had higher (P < 0.05) growth performance compared with birds fed the NC diet across all groups. Similarly, phosphorus (P) and calcium (Ca) digestibility and retention of birds fed the NC were lower (P < 0.05) as compared with birds fed the PC diet while birds fed the phytase supplemented diets had higher mineral digestibility and retention (P < 0.05) compared with birds on the NC diet. Age effect was evaluated by comparing the performance of birds fed the experimental diets for 2 d until d 8, 14, and 22. Birds fed until d 14 had the highest impact of the NC diet on mineral utilization, and the largest improvement of phytase on mineral utilization as compared with birds fed until d 8 and 22. Similarly, when feeding length effect was considered, birds fed for a shorter period had greater response to phytase (P < 0.05) on nutrient utilization than birds fed for a longer period at d 14 and 22. Tibia ash was higher (P < 0.05) in birds fed phytase supplemented diets for a longer period (i.e. 16 d) compared with birds fed or 2 or 5 d. The results from this study observed that age and duration of feeding influenced phytase efficacy especially in younger birds fed for a short period. However, it could not be determined if feeding birds for a short period at different ages in the starter phase would have a similar effect.<br>In study 2, the effects of age and feeding low P diets to birds for a short period of time on phytase efficacy and super dosing were evaluated at two critical points in the starter phase. This study had 3 × 2 × 2 factorial arrangements of treatments comprising 3 diets; a PC, NC, and a NC with phytase supplemented at 2,000 phytase units/kg; and 2 ages (i.e d 14 and 22) and 2 feeding lengths (i.e 2-d and 5-d). Thus, birds were fed the experimental diets from d 12 to 14, 9 to 14, 20 to 22, and 17 to 22 respectively. Results observed were similar to the first study. Birds fed the NC diet had lower (P < 0.01) performance as compared with birds fed the PC diets across all age and feeding length groups. Similarly, birds fed diets with the super dose level of phytase had greater growth performance (P < 0.01) compared with birds fed the NC diets. When age effect was considered, birds fed for 2 or 5 d until d 14 had the greatest improvements of phytase on nutrient utilization and bone mineralization compared with birds fed for both periods until d 22. When effect of feeding was considered, birds fed for 2-d at both ages had greater responses to phytase in performance and nutrient utilization compared with birds fed for 5-d at both ages. Plasma myo-inositol was higher (P < 0.01) in birds fed the super dose level of phytase compared with birds fed the NC diet.<br>In summary, we could conclude that the efficacy of phytase both at 1,000 and 2,000 FTU/kg was higher in birds fed for 2 d until d 14 as compared with the other groups. This could potentially help in designing studies to evaluate new phytase products or for comparing the efficacy of phytase from various sources. Feeding broiler chickens during the suggested time phase would potentially reveal the maximum efficacy of the phytase product.<br>
35

Phosphorus in pig diets : effect of liquid feeding, phosphorus levels and phytase supplementation on digestibility and performance /

Lyberg, Karin, January 2006 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 4 uppsatser.
36

Structural insight into dephosphorylation Klebsiella sp. ASR1 phytase PhyK and human protein tyrosine phosphatase SHP2

Böhm, Kerstin January 2009 (has links)
Zugl.: Berlin, Freie Univ., Diss., 2009
37

Production de microcapsules de phytase par atomisation: influence sur la disponibilité des nutriments chez la truite arc-en-ciel (Oncorhynchus mykiss) /

Benchabane, Samir. January 2005 (has links)
Thèse (M.Sc.)--Université Laval, 2005. / Bibliogr. Publié aussi en version électronique.
38

Feed processing challenges facing the swine industry

De Jong, Jon January 1900 (has links)
Doctor of Philosophy / Animal Sciences and Industry / Joel M. DeRouchey / Eight experiments using a total of 2,964 finishing pigs and 2,947 feed, phytase, or premix samples were used to determine the effects of: 1) wheat source, particle size and feed form on finishing pig performance; 2) feed form feeding strategies; 3) fine generation from pellets during feed manufacturing and delivery, and 4) thermal stability and shelf life of phytase products. Exp. 1 and 2 evaluated wheat sources, particle size, and diet form for finishing pigs. Fine gound hard red winter wheat fed in meal form improved G:F and nutrient digestibility, whereas wheat ground from ~700 to 250 µ in pelleted diets did not influence growth or carcass traits. Feeding hard red winter wheat improved ADG and ADFI compared with feeding soft white winter wheat. In Exp. 3, pellet feeding regimens were used to evaluate finishing pig performance and stomach morphology. Feeding pelleted diets improved G:F but increased stomach ulceration and pig removals; however, rotating pellets and meal diets provided an intermediate G:F response with fewer stomach ulcers and pig removals. Experiments 4 to 6 investigated fines formation during pelleted feed manufacturing and delivery. Pellet quality worsened as pellets were transported through the feed mill post pelleting and during delivery. Unloading speed or feed line location had little effect on pellet quality. There were significant differences between the fines and pellet nutrient profiles as noted by the increased concentration of ADF, crude fiber, Ca, ether extract, and starch in the fines and decreased CP and P when compared to pellets. In Exp. 7 and 8, the thermal stability and shelf life of 4 commercial phytase products was determined. Increasing conditioning temperatures decreased phytase stability regardless of product. Phytase activity was affected by storage duration, temperature, product form, and phytase source. Pure products stored between 15 and 22˚C were the most stable and premixes were affected by longer storage times and higher temperatures.
39

Efeito da suplementação de enzimas sobre o processamento e digestibilidade de dietas extrusadas para cães contendo farelo de trigo

Sá, Fabiano César [UNESP] 21 February 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-21Bitstream added on 2014-06-13T20:30:46Z : No. of bitstreams: 1 sa_fc_me_jabo.pdf: 521957 bytes, checksum: 8f14fb22de3782d8087ec8fc4daa49de (MD5) / Granotec do Brasil S.A / O farelo de trigo é um coproduto da indústria alimentícia com custo acessível e importante fonte de fibra e amido que vem sendo empregado para cães. Contudo, este ingrediente apresenta Polissacarídeos Não Amiláceos (PNA’s), que não são digeridos pelos cães e podem causar distúrbios gastrintestinais, que interferem na absorção dos nutrientes. Com o intuito de aumentar a biodisponibilidade dos nutrientes do farelo de trigo em dietas extrusadas para cães, avaliou-se a suplementação com uma mistura de enzimas sobre o coeficiente de digestibilidade dos nutrientes, qualidade e produção de fezes e parâmetros fermentativos intestinais. Foram formuladas duas dietas experimentais isonutritivas. A primeira possuía apenas milho e quirera de arroz como fonte de amido e fibra de cana de açúcar como fonte de fibra, que foi denominada ração controle negativo (CN). A segunda formulação apresentava 25% de farelo de trigo e foi desdobrada em quatro tratamentos: CP - dieta controle positivo, com farelo de trigo e sem adição de enzimas; ENZ1 – com enzimas na mistura antes da extrusão; ENZ2 - com as enzimas do ENZ1 mais α-amilase, na mistura antes da extrusão; ENZ2Pex - com as enzimas do ENZ2 após extrusão, como cobertura. O experimento seguiu delineamento em blocos casualizados no tempo, com dois blocos de 15 animais, três animais por tratamento em cada bloco e seis cães por tratamento. Os dados obtidos foram submetidos à análise de variância e as médias dos cinco tratamentos comparadas pelo teste de Tukey a 5% de probabilidade. Os resultados foram, também, avaliados por meio de contrastes ortogonais pré-estabelecidos, a 5% de probabilidade. A adição de farelo de trigo levou à redução da digestibilidade dos nutrientes (p<0,05). A mistura de enzimas não resultou em diferenças na digestibilidade, qualidade das fezes e produtos de fermentação microbiana fecal... / The wheat bran is a byproduct of the food industry with affordable and important source of fiber and starch that has been used for dogs. However, this ingredient has no-starch polysaccharides (NSP), which are not digested by dogs and can cause gastrointestinal disturbances, which interfere with absorption of nutrients. In order to increase the bioavailability of nutrients in wheat bran extruded diets for dogs, we assessed whether supplementation with a mixture of enzymes on the digestibility of nutrients, quality and production of feces and intestinal fermentation parameters. Two experimental diets were formulated isonutrients. The first had only corn and broken rice as a source of starch and sugar cane fiber as a fiber source, which was designated negative control diet (NC). The second formulation showed a 25% wheat bran and was split into four treatments: CP - positive control diet with wheat bran and without enzymes; ENZ1 - with enzymes in the mixture before extrusion; ENZ2 - with enzymes ENZ1 more α-amylase in the mixture before extrusion; ENZ2Pex - with enzymes ENZ2 after extrusion, as cover. The experiment followed a randomized block design in time, with two blocks of 15 animals, three animals per treatment in each block and six dogs per treatment. The data were subjected to analysis of variance and the mean of five treatment groups were compared by Tukey test at 5% probability. The results were also evaluated using orthogonal contrasts pre-set at 5% probability. The addition of wheat bran led to reduced digestibility of nutrients (p <0.05). The mixture of enzymes resulted in no differences in digestibility, stool quality and fecal microbial fermentation products (p> 0.05). The productivity of feed increased with the addition of the mixture of enzymes ENZ2, reducing the cost of eletctricity production in the diet
40

Detanificação e desfitinização de grãos de sorgo (Sorghum bicolor) por tanase e fitase e estudo biologico / Sorghum gruels (Sorghum bicolor) detanification and defitinization with tannase and phytase and biological study

Schons, Patricia Fernanda 14 August 2018 (has links)
Orientador: Gabriela Alves Macedo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-14T10:38:34Z (GMT). No. of bitstreams: 1 Schons_PatriciaFernanda.pdf: 1271406 bytes, checksum: 668e62b416afd72ff47587e7425cecd0 (MD5) Previous issue date: 2009 / Resumo: Este trabalho visou avaliar o efeito do fungo Paecilomyces variotti e das enzimas fitase e tanase sobre fatores antinutricionais, taninos e fitatos presentes no sorgo tipo vassoura. A enzima tanase produzida pelo fungo Paecilomyces variotti apresentou atividade enzimática de 626U/g, além desta enzima, estavam presentes no extrato enzimático, com menor atividade protease, carboximetilcelulase, polimetilgalacturonase e fitase. A fitase empregada foi comercial (NATUPHOS ¿ BASF) e apresentou atividade de 660U/g. O sorgo utilizado neste estudo possui 13,6% de proteína, 4,2% de lipídeos, 1,7% de cinzas e 80,5% de carboidratos, elevada concentração de compostos fenólicos, especialmente taninos condensados e 226mg/100g de sorgo de fósforo inorgânico. O sorgo foi preparado e tratado com Paecilomyces variotti, tanase e fitase em diferentes combinações. As respostas diminuição de tanino e aumento de fósforo foram avaliados, os melhores resultados foram obtidos quando a farinha de sorgo foi tratada com tanase e fitase durante 5 dias. Por meio de planejamento experimental foi feito estudo do tratamento de sorgo com as enzimas fitase e tanase, o qual indicou a relação entre sorgo:água, como sendo a variável mais significativa para o processo. O processamento (maceração e fervura) e adição das enzimas foram efetivos na redução de taninos e aumento de fósforo, quando comparamos estes resultados com o sorgo cru, porém, as diferentes concentrações das enzimas não tiveram efeito sobre os parâmetros avaliados. Baseado nos resultados expostos, o sorgo para a elaboração das dietas foi tratado com a concentração inferior de enzimas estudada (100U/Kg). O estudo in vivo mostrou que a dieta elaborada com sorgo tratado enzimaticamente foi efetivo na melhoria da digestibilidade aparente de fósforo, na diminuição da excreção de fósforo, resultaram em melhores índice bioquímico para glicose e colesterol, apresentaram uma menor atividade de enzimas hepáticas aspartato aminotrasnferase (AST) e alanina aminotransferase (ALT), comparando com sorgo cru. No entanto, não teve efeito significativo na melhoria do ganho de peso, da digestibilidade aparente de proteína, na concentração de fósforo, ferro e cálcio plasmático, bem como na concentração de mineral contido no fêmur / Abstract: This work aimed assess the fungus Paecilomyces variotti and enzymes phytase, tannase effects on the antinutritional factors, tannins and phytates present in sorghum. The tannase produced by the fungus Paecilomyces variotti has enzymatic activity of 626U/g, in addition this enzyme were present in the enzymatic extract protease, in less activity protease, carboxymetilcellulase, polymetilgalacturonase and phytase. The phytase used is commercially (NATUPHOS ¿ BASF) and has activity of 660U/g. The sorghum utilized in this study has 13.6% protein, 4.2% of lipids, 1.7% ash and 80.5% carbohydrate, high concentration of phenolic, mainly condensed tannins and inorganic phosphorus 226mg/100g sorghum. The sorghum was prepared and treated by using Paecilomyces variotti, tannase and phytase in different combinations. The decrease in the tannins and increase in the phosphorus were evaluated, the best results were obtained when sorghum flour was treated with tannase and phytase for 5 days. Through experimental design were made a study about sorghum treated by the enzymes tannase and phytase, which indicated the relationship between sorghum:water, as the most significant variable in the process. The processing (soaking and boiling) and addition of enzymes were effective in reducing tannin and increase phosphorus, when comparing these results with the raw sorghum, however, different concentrations of the enzymes had no effect on the parameters evaluated. Based on the results above, the sorghum for the preparation of the diets were treated with lower concentration of enzymes studied (100U/Kg). The in vivo assay showed that the diet prepared using sorghum treated enzimaticaly was effective in improving digestibility of phosphorus, reducing the phosphorus excretion, resulting in better biochemical index for glucose and cholesterol, showed a lower activity of liver enzymes aspartate aminotransferase (AST) and alanin aminotransferase (ALT), compared with raw sorghum. However, it had no significant effects in improve weight, the apparent digestibility of protein, and the concentration of phosphorus, iron and calcium in the plasma and mineral content in the femur / Universidade Estadual de Campi / Ciência de Alimentos / Mestre em Ciência de Alimentos

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