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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.
11

Evaluation of phytase enzymes on performance, bone mineralisation, carcass characteristics and small intestinal morphology of broilers fed maize soya bean diets

Van Emmenes, Liesel 04 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The use of phytase enzymes to liberate phosphorus and other phytate bound nutrients in monogastric animal diets are becoming common practice and several commercial phytase enzymes are available on the market. Phytase manufacturers supply nutritionists with matrix values for the specific phytase, enabling nutritionists to effectively decrease the dietary concentrations of phosphorus and nutrients during diet formulation. A 32 day experiment was conducted with 5120 broiler chicks fed diets supplemented with different commercial phytase enzymes (1000 FYT or 1500 FYT HiPhos/kg diet, 1500 FYT Ronozyme/kg diet, 500 FTU Natuphos/kg diet or 500 FTU Phyzyme/kg diet) at levels recommended by the manufacturers and with similar phosphorus equivalence. The nutrient content of the diets supplemented with 500 FTU Natuphos, 500 FTU Phyzyme 1500 Ronozyme and 1000 FYT HiPhos were reduced according to the matrix values of 1000 FYT/kg HiPhos, whilst the diet supplemented with 1500 FYT HiPhos /kg diet was reduced according to the matrix values 1500 FYT HiPhos. The objectives of this study were threefold: (i) to confirm the matrix value for a newly developed phytase (HiPhos, DSM Nutritional Products, Basel, Switzerland), at two different inclusion levels, using weight gain and bone parameters of broilers as response criteria; (ii) to compare production and bone parameters of broilers reared on three different commercial phytases to broilers reared on HiPhos (iii) to investigate the effect that supplementation of these four phytases has on water intake, carcass characteristics, organ weights and gastrointestinal tract morphology of broilers. The matrix values for 1500 FYT HiPhos were confirmed by using live weight gain as response criteria, but results for bone parameters were insufficient in confirming the matrix values. The matrix values for 1000 FYT HiPhos were confirmed by the results for tibia weight and tibia strength, but results for weight gain were insufficient to confirm the values. The matrix values for 1000 FYT HiPhos and 1500 FYT HiPhos could not be confirmed nor disproved, nevertheless results from the current trial proved diets supplemented with HiPhos to be more economically viable when compared to the standard commercial broiler diet. Total feed and water intake were not influenced by phytase supplementation. Production parameters (live weight, feed intake, feed conversion ratio, European production efficiency factor and average daily gain) and bone parameters (tibia strength, fat free tibia weight, fat free tibia ash and mineral content) did not differ between phytase treatments and therefore all the commercial phytases were equally effective to the HiPhos phytase. Furthermore, results indicate that the investigated phytases had no effect on internal organ weight or gastrointestinal tract morphology in broilers. Overall the results obtained from the study indicate that the use of phytase as feed additive has no negative effects on growth performance, carcass characteristics or bone parameters. No major differences for the production and bone parameters were observed between broilers supplemented with different phytases. Therefore the costs of these phytases can be the determining factor when nutritionists decide which commercial phytase to use. / AFRIKAANSE OPSOMMING: Die gebruik van fitase ensieme in die diëte van enkelmaagdiere om fitaat-gebonde fosfor en voedingstowwe vry te stel, word al hoe meer algemeen in die bedryf en verskeie kommersiële fitase ensieme is in die mark beskikbaar. Die ensiemvervaardigers verskaf die fitases se matryswaardes aan voedingskundiges wat hul in staat stel om die fosfor- en nutrientvlakke in die dieet effektief te verminder. ´n Studie met 5120 braaikuikens was vir 32 dae uitgevoer. Die braaikuiken diëte was met verskillende kommersiële fitase ensieme (1000 FYT & 1500 FYT HiPhos/kg dieet, 1500 FYT Ronozyme/kg dieet, 500 FTU Natuphos/kg dieet of 500 FTU Phyzyme/kg dieet) aangevul. Die nutrientvlakke van die diëte wat met fitase aangevul was, was verminder volgens die matryswaardes van 1000 FYT of 1500 FYT HiPhos fitase. Die doelstellings van hierdie studie was drievoudig: (i) om die matryswaardes van ´n nuwe fitase (HiPhos, DSM Nutritional Products, Basel, Switzerland) by twee verskillende insluitingsvlakke te bevestig deur massa toename en been parameters as reaksie maatstawwe te gebruik (ii) om produksie- en been parameters van braaikuikens, wat een van drie kommersiële fitase ensieme as voerbymiddel ontvang het, met dié van braaikuikens wat die nuwe ensiem gevoer was te vergelyk (iii) om die effek wat fitase op water inname, karkaseienskappe, orgaan massas en spysverteringskanaal morfologie het te bestudeer. Die matryswaardes vir 1500 FYT HiPhos was bevestig deur lewendige massa toename as respons kriteria te gebruik, maar resultate vir die been parameters was onvoldoende om die matryswaardes te bevestig. Die matryswaardes vir 1000 FYT HiPhos was slegs bevestig deur die resultate vir die breeksterktes van die tibias, maar resultate vir massa toename was onvoldoende om die matryswaardes te bevestig. Dus kon die matryswaardes vir die HiPhos fitase nie bevestig of verkeerd bewys word nie. Desondanks het die resultate in die huidige proef bewys dat diëte wat met HiPhos aangevul was meer ekonomies as die kommersiële braaikuiken dieet is. Totale voer- en water-inname was nie deur die aanvulling van fitase beïnvloed nie. Produksie parameters (lewendige massa, voeromset, die Europese produksie doeltreffendheids faktor, gemiddelde daaglikse toename) en been parameters (tibia breeksterkte, vet vrye tibia massa, vet vrye tibia as en mineraal-inhoud) het nie verskil tussen die fitase behandelings nie en dus was al die kommersiële fitases ewe effektief. Vanuit die studie is getoon dat die gebruik van fitase as ´n voerbymiddels geen negatiewe effek op groei, karkas eienskappe of been parameters het nie en dat fitase ook nie die orgaan gewigte of die spysverteringskanaal morfologie van braaikuikens beïnvloed nie. Geen groot verskille in produksieen been parameters was waargeneem tussen hoenders wat verskillende fitases as voerbymiddel ontvang het nie, daarom kan die koste van die ensiem die bepalende faktor wees as voedingkundiges die keuse maak tussen hierdie kommersiele fitases.
12

Effects of dietary flaxseed and ℓ-topopherol supplementation on broiler's performance, fatty acid composition in muslce [sic] tissues and meat storage stability

Kalinowski, Antonio. January 1999 (has links)
Experiments were conducted to investigate the effects of dietary fat, vitamin E(Vit. E) and selenium(Se) supplementation on the performance, fatty acid(FA) composition, lipid oxidation on blood and the oxidative stability of muscle tissues (breast and thigh) during refrigerated storage of broiler chickens fed high levels of flaxseed(FXS). Four hundred and eighty d-old broiler chicks were fed experimental diets for a 3 wk period, which consisted of the combination of two dietary fat sources: fullfat soybean(FFSB) and FXS; 3 Vit. E levels: 10, 40 and 80 IU/kg and two Se levels: 0.15 and 0.30ppm (Exp. I). Four hundred and forty d-old chicks were fed on FFSB diets supplemented with 10, 80, and 160 IU of Vit. E/kg, FXS diets supplemented with 10, 40, 80, 120, 160 and 200 IU of Vit. E/kg, corn-soybean based diet (control), and on a commercial diet for 21 days (Exp. II). For Exp. III, 1680 (840 of each sex) d-old broiler chicks were raised up to 41d. Three basal diets containing 10% FXS and 3 levels of Vit. E: 60-, 90- and 160 IU/kg were formulated for 3 age periods: starter (0--3wk), grower (3--5 wk) and finisher (5--6wk). Three groups of birds were fed these basal diets, while 3 other groups were fed the diet containing 160 IU of Vit. E either during the starter, grower or finisher phase (diets supplemented with 60 IU/kg were given in the two remaining phases). (Abstract shortened by UMI.)
13

The effect of two Lactobacillus strains and an acidophilic fungus on production and immune responses of broiler chickens /

Huang, Ming-Kuei, 1969- January 2003 (has links)
Three potential probiotics, Lactobacillus acidophilus, Lactobacillus casei and the fungus Scytalidium acidophilum were prepared in different ways. They were evaluated for their effects on performance and immune responses in broiler chickens in two 6-week trials. In the first trial, probiotics were orally administered at the ages of day 1 and day 8. There were no differences between live and disrupted cells. However, cobalt-containing cells had improved effects numerously in comparison with non cobalt-containing cells. As a result, these three disrupted probiotics, each in two different concentrations, were sprayed onto a mash basal feed before pelleting in the second trial. Improved feed intake (up to 6%) and body weight gain (up to 7%) were observed in all probiotic treatments. The anti-KLH IgA and IgG titers of probiotic-treated chickens were not significantly different from the negative controls in both trials. In summary, disrupted and cobalt-containing probiotics were proved to enhance the performance of broiler chickens and are promising for commercial application. In addition, a new fungal mycelium, Scytalidium acidophilum, was suggested to be a good probiotic to improve the growth of broilers.
14

Effects of dietary flaxseed and ℓ-topopherol supplementation on broiler's performance, fatty acid composition in muslce [sic] tissues and meat storage stability

Kalinowski, Antonio. January 1999 (has links)
No description available.
15

The effect of two Lactobacillus strains and an acidophilic fungus on production and immune responses of broiler chickens /

Huang, Ming-Kuei, 1969- January 2003 (has links)
No description available.
16

The effects of a multiple-enzyme combination in maize-soya diets for broiler chickens

Fourie, Juan-Louis 03 1900 (has links)
Thesis (MscAgric (Animal Sciences))--University of Stellenbosch, 2007. / The effect of a multiple-enzyme combination in mash and pelleted vegetarian maize-soya diets for broilers was evaluated in terms of apparent excreta- and ileal nitrogen- and amino acid digestibility and production performance. Two separate digestibility trials and one performance trial were conducted. For Trial 1, the apparent nitrogen (N) - and amino acid (AA) digestibility was determined by the collection of the excreta (total collection method) and in Trial 2 from digesta collected at the terminal ileum (ileal digestibility method). Production performance was also recorded in Trial 1. In Trial 3, the effect of the multipleenzyme combination in potentially improving performance of broilers in commercial conditions was evaluated. Broilers were fed a balanced- and low apparent energy (AME) vegetarian maize-soya diet with the addition of the multiple-enzyme combination. The addition of enzymes improved the apparent excreta- and ileal N digestibility of the mash diets during the period 14-21 d, and the ileal N-digestibility of the pelleted diets at 28 and 35 d of age. Conflicting results with regard to apparent excreta- and ileal AA digestibility were found. By both methods the digestibilities of threonine (Thr), methionine (Met) and phenylalanine (Phe) (14-21 d) and Cys (22-28 d and 29-35 d) were improved by the addition of the enzyme combination to the mash diets. Over the entire experimental period (14-35 d) the ileal digestibilities of histidine (His), Cys and leucine (Leu)of the mash diets were improved by 0.2 %, 0.2 % and 1.9 % respectively, following enzyme addition. By both methods the digestibilities of Thr, arginine (Arg), Met, Cys, Phe and Leu (14-21 d), serine (Ser), Arg, glutamic acid (Glu), Val, His, aspartic acid (Asp), lysine (Lys), proline (Pro), Met, tyrosine (Tyr), Phe and Leu (22-28 d), and Pro (29-35 d) were improved by the combination of enzymes and pelleting. For the entire experimental period (21-35 d), the ileal digestibilities of Ser, His, Lys, Met, Tyr, Cys, Phe and Leu was improved by the combination of enzymes and pelleting, indicating enzymatic activity was not destroyed by cold pelleting at 60 - 80º. The improvements in apparent nitrogen- and AA digestibilities were, in most cases, not reflected in production performance, although the combination of enzymes and pelleting resulted in improved body weight gain (BWG) for the first two weeks of chicks life and significantly improved the feed conversion ratio (FCR) during the second week of the chicks’ life. The effect of the multiple-enzyme combination on the production performance of broilers on a low AME- and commercial diet was mostly non-significant except for a significantly lower feed iii intake of the balanced diet for the fourth and fifth week of chick’s life following enzyme addition. A financial calculation showed, however, that the enzyme combination might increase profitability of a nutritionally balanced vegetarian maize-soya diet for broilers.
17

The evaluation of larvae of Musca domestica (common house fly) as protein source for broiler production

Pretorius, Q. 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The objective of this study was to evaluate the use of Musca domestica (common house fly) larvae meal, as protein source, for broiler production. This was done by investigating the nutritive value of house fly larvae meal together with its total tract digestibility, potential toxicity and carcass characteristics of the broilers supplemented with house fly larvae meal. The proximate analysis of house fly larvae meal show that it contained, on a dry matter basis, a gross energy value of 20.10 MJ/kg, 60.38% crude protein, 14.08% crude fat and 10.68% ash and that the house fly pupae contained a gross energy of 20.42 MJ/kg, 76.23% crude protein, 14.39% crude fat and 7.73% ash. House fly pupae meal had the closest match of amino acid profile when compared with the ideal amino acid profile required by broilers and it has arginine relative to the lysine content closer to the ideal amino acid profile than the house fly larvae meal. The essential fatty acid, linoleic acid, was found at levels of 26.25 and 36.27% of the total fats for the house fly larvae and pupae meal respectively. House fly larvae meal supplementation did not induce gizzard erosion or showed toxicity (regarding the gastro intestinal tract, immune system and organ stress) in broilers. Results revealed that house fly pupae meal had higher total tract digestibilities for most nutrients than of the house fly larvae meal. House fly larvae meal had a crude protein total tract digestibility of 69% and that of pupae meal was 79%. Both larvae and pupae meal had high amino acid total tract digestibilities of all the amino acids analysed. The house fly larvae and pupae meal had an apparent metabolizable energy (AME) value of 14.23MJ/kg and 15.15MJ/kg respectively. The larvae meal total tract crude fat and crude fibre digestibilities were 94% and 62% respectively. The pupae meal total tract crude fat and crude fibre digestibilities were 98% and 58% respectively. House fly larvae meal supplementation in a three phase feeding system significantly increased average broiler live weights at slaughter, total feed intake, cumulative feed intake as well as average daily gain (ADG) when compared to commercial maize: soya oil cake meal diet. In direct comparison of larvae inclusion levels with fishmeal in isonitrogenous and isoenergetic diet, no significant differences were observed between a 10% house fly larvae and a 10% fish meal diets regarding performance characteristic. The 25% house fly larvae meal diet yielded significantly better average broiler live weights at slaughter, total feed intake, cumulative feed intake (from the second week until slaughter) as well as average daily gain when compared to the 25% fish meal diet in the growth phases. Carcass characteristics of the 10% larvae, 10% fishmeal and commercial diets were compared. Chicks that received either the 10% house fly larvae meal or 10% fish meal supplementation produced significantly heavier carcasses and breast muscle portions than the chicks that received the commercial maize: soya oil cake meal. No treatment differences were found regarding breast and thigh muscle colour or pH. This study showed that house fly larvae meal can be regarded as a safe protein source that can be used to replace other protein sources and that has the ability to promote broiler performance without having any detrimental effects on carcass characteristics. / AFRIKAANSE OPSOMMING: Die evaluasie van Musca domestica (gewone huisvlieg) larwe meel as ‘n proteien bron vir braaikuiken produksie Die doel van die studie was om die effek van Musca domestica (gewone huisvlieg) larwe meel, as ‘n protein bron, in braaikuikens te evalueer. Dit was gedoen deur die nutrient waarde van huisvlieg larwe meel saam met die totale spysvertering verteerbaarheid, moontlike toksiesiteit en karkas-eienskappe van braai kuikens te evalueer. Laboratoruim analiese toon dat huisvlieg larwe meel 20.10 MJ/kg bruto energie, 60.38% ru- protein, 14.08% ru- vet en 10.68% as bevat en huisvlieg papie meel 20.42 MJ/kg bruto energie, 76.23% ru- protein, 14.39% ru- vet en 7.73% as bevat. Huisvlieg papie meel stem die meeste ooreen met die idiale amino suur profiel soos wat benodig word deur braaikuikens en dit het ‘n arginien tot lisien verhouding wat die meeste ooreenstem met die idiale amino suur profiel in vergelyking met huis vlieg larwe meel. Die essensiele vet suur, linolien suur, was geanaliseer teen vlakke van 26.25- en 36.27% van die totale vette onderskeidelik vir huisvlieg larwe- en papie meel. Huisvlieg larwe meel vervanging het nie spiermaag erosie of enige ander toksiese effekte te veroorsaak nie. Resultate het getoon dat huisvlieg papie meel, in vergelyking met larwe meel, het ‘n hoër totale spysvertering verteerbaarheid vir meeste van die nutrient. Die huisvlieg larwe meel het ‘n totale ru- protein spysvertering verteerbaarheid van 69% en die van papie meel van 79%. Beide larwe en papie meel het hoë amino suur spysvertering verteerbaarheid. Larwe meel en papie meel het skynbare metaboliseerbare energie waardes van 14.23MJ/kg en 15.15%MJ/kg onderskeidelik. Die larwe meel het ‘n ru-vet en ru- vesel spysvertering verteerbaarheid van 94% en 62% onderskeidelik, waar die papies ‘n ru-vet en ru- vesel spysvertering verteerbaarheid van onderskeidelik 98% en 58% het. Huisvlieg larwe meel vervanging in ‘n drie fase voer stelsel het getoon om die gemiddelde braaikuiken lewende gewigte by slag, totale voer iname, sowel as die gemiddelde daaglikse toename te verhoog waneer dit vergelyk word met ‘n kommersiele mielie- soya olie koek dieet. Geen mekwaardige verskille was waargeneem toe die 10% larwe meel dieet direk met die 10% vismeel diet vergelyk was rakende enige produksie einskappe gemeet nie. Die 25% larwe meel dieet het merkwaardig beter gemiddelde braaikuiken lewende gewigte by slag, totale voer iname, sowel as die gemiddelde daaglikse toename getoon wanneer vergelyk word met die 25% vismeel dieet gedurende die verskeie groei fases. Karkas eienskappe van die 10% larwe meel, 10% vismeel en die kommersiele diete was gevergelyk. Kuikens wat 10% larwe meel en 10% vismeel in die diete ontvang het, het swaarder karkasse gelewer met swaarder borsie massas wanneer vergelyk word met die kommersiele mielie- soya olie koek dieet. Geen behandelings verskille was gevind rakende die borsie- en dy spier kleure of pH nie. Die studie toon dat huisvlieg larwe meel as ‘n veillige protein bron kan beskou word, wat gebruik kan word om ander protein bronne te vervang. Huisvlieg larwe meel het ook die vermoë om braaikuiken produksie te verhoog sonder om enige negitiewe effekte rakende die karkas eienskappe te toon nie.
18

The influence of processing of soyabeans and sunflower seed on their energy and amino acid availability for poultry

De Beer, Marc 03 1900 (has links)
Thesis (MScAgric)--Stellenbosch University, 2003. / ENGLISH ABSTRACT: 1. The effect of heat-treatment and dehulling of full-fat soya (Glycine max) on AMEn' amino acid availability and broiler performance. Heat treatment and dehulling of full-fat soya were evaluated in terms of their effect on AMEn, apparent amino acid availability and broiler performance. Four products were tested: raw whole soya (RWS), raw dehulled soya (RDS), extruded whole soya (EWS) and extruded dehulled soya (EDS). Trials were conducted to determine AMEn values and apparent amino acid availability of the products. A 42-day broiler trial was conducted to measure the effect of extrusion and dehulling on broiler performance. Test products were added to the diets at levels up to 263.2 g/kg in the starter diet and 260.0 g/kg in the finisher diet. Results indicated that extrusion cooking improved AMEn and apparent amino acid availability. This was reflected in the improved performance of broilers fed extruded soya as compared to raw soya. Increasing amounts of RWS and RDS led to decreases in mass and intake and poor feed conversion ratio (FeR) due to the presence of anti-nutritional factors. Broilers fed EWS were heavier, consumed more feed and had better FeR than those fed RWS or RDS. Dehulling improved AMEn (EWS: 13.75 MJ/kg vs EDS: 15.09 MJ/kg) and rendered a product with slightly higher levels of total amino acids. Broiler performance did not reflect this as there was no difference in mass, intake or FeR between broilers fed increasing levels of EWS or EDS. Lysine and arginine were less available in EDS than EWS indicating the possible over-cooking of EDS. Levels of EWS and EDS of 263.2 g/kg in the starter and 260.0 g/kg in the finisher supported maximum broiler performance. 2. The effect of heat-treatment and dehulling of full-fat sunflower (Helianthus annuus) on AMEm amino acid availability and broiler performance. Heat treatment and dehulling of full-fat sunflower were evaluated in terms of their effect on AMEn, apparent amino acid availability and broiler performance. Four products were tested: raw whole sunflower (RWSF), raw dehulled sunflower (RDSF), extruded whole sunflower (EWSF) and extruded dehulled sunflower (ED SF). Trials were conducted to determine AMEn values and apparent amino acid availability of the products. A 42-day broiler trial was conducted to measure the effect of expansion and dehulling on broiler performance. Test products were added to the diets at levels up to 115.0 glkg in the starter diet and 181.5 glkg in the finisher diet. Dehulling rendered a product with higher crude protein, ether extract, amino acid and AMEn values. AMEn was only slightly improved by expansion. The AMEn values obtained were: RWSF: 16.03 MJ/kg, RDSF: 18.87 MJ/kg, EWSF: 16.22 MJ/kg, EDSF: 19.49 MJ/kg. Dehulling had no effect on apparent amino acid availability. Expansion did not affect apparent amino acid availability of dehulled full-fat sunflower but had a negative influence on apparent amino acid availability of whole sunflower seeds. This highlights the possible dangers of reduced protein quality as a result of overprocessing. No differences were observed in terms of mass, intake and feed conversion ratio of broilers fed any of the products during the 42-day broiler growth trial. All products supported optimum broiler performance at levels up to 115.0 glkg in the starter diet. For the finisher diets, optimum performance was maintained at levels of 181.5 glkg, for RDSF and EDSF, while performance of broilers fed RWSF and EWSF was optimal up to 145.2 glkg. / AFRIKAANSE OPSOMMING: 1. Die invloed van hitte-behandeling en ontdopping van volvetsojabone (Glycine max) op SMEm skynbare aminosuur beskikbaarheid en braaikuikenprestasie. Hitte-behandeling en ontdopping van volvetsojabone is ge-evalueer in terme van hul invloed op stikstof gekorrekteerde skynbare metaboliseerbare energie (SMEn) waardes, skynbare aminosuur beskikbaarheid en braaikuikenprestasie. Vier produkte is getoets: rou heel sojabone (RWS), rou ontdopte sojabone (RDS), geekstrueerde heel sojabone (EWS) en geekstrueerde ontdopte sojabone (EDS). Proewe is uitgevoer om die SMEn waardes en skynbare aminosuur beskikbaarheid van die vier produkte te bepaal. Gedurende 'n braaikuikengroeitoets van 42 dae is die invloed van hittebehandeling (ekstrusie) en ontdopping op braaikuikenprestasie gemeet. Die vier toetsprodukte is ingesluit in die aanvangsdieet teen peile van tot 263.2 g/kg en teen peile van tot 260.0 g/kg in die afrondingsdieet. Resultate het getoon dat ekstrusie die SMEn waardes en skynbare aminosuur beskikbaarheid verbeter het. Braaikuikens wat geekstrueerde soja ontvang het, het beter gepresteer as braaikuikens wat rou soja ontvang het. Verhoogte insluitings van RWS en RDS het gelei tot verlagings in massa toename en voerinname en swak voeromsetverhoudings (VOV), as gevolg van die teenwoordigheid van anti-voedings faktore. Braaikuikens wat EWS ontvang het, was swaarder, het meer ingeneem en het beter vav gehad as die wat RWS of RDS ontvang het. Ontdopping het SMEn verhoog (EWS: 13.75 MJ/kg vs EDS: 15.09 MJ/kg) en ontdopte produkte het klein hoeveelhede meer aminosure bevat. Dit het egter nie in braaikuikenprestasie gewys nie. Daar was geen verskille in massa, voerinname en vav tussen braaikuikens wat EWS of EDS ontvang het. Lisien en arginien was minder beskikbaar in EDS as EWS wat op die moontlike oorprosessering van EDS dui. Vlakke van EWS en EDS van 263.2 g/kg in die aanvangsdieet en 260.0 g/kg In die afrondingsdieet het maksimale braaikuikenprestasie ondersteun. 2. Die invloed volvetsonneblosaad van hitte-behandeling (Helianthus annuus) en ontdopping van op SMEo, skynbare aminosuur beskikbaarheid en braaikuikenprestasie. Hitte-behandeling en ontdopping van volvetsonneblomsaad is geevalueer in terme van hul invloed op stikstof gekorrekteerde skynbare metaboliseerbare energie (SMEn) waardes, skynbare aminosuur beskikbaarheid en braaikuikenprestasie. Vier produkte is getoets: rou heel sonneblomsaad (RWS), rou ontdopte sonneblomsaad (RDS), geekspandeerde heel sonneblomsaad (EWS) en geekspandeerde ontdopte sonneblomsaad (EDS). Proewe is uitgevoer om die SMEn waardes en skynbare aminosuur beskikbaarheid van die vier produkte te bepaal. Gedurende 'n braaikuikengroeitoets van 42 dae is die invloed van hitte-behandeling (ekspansie) en ontdopping op braaikuikenprestasie gemeet. Die vier toetsprodukte is ingesluit in die aanvangsdieet teen peile van tot 115.0 g/kg en teen peile van tot 181.5 g/kg in die afrondingsdieet. Ontdopte sonneblomsaad het hoer peile van ruproteien, eter-ekstrak en aminosure as heel sonneblomsaad. SMEn waardes is ook hoer vir ontdopte sonneblomsaad. Hitte-behandeling het SMEn waardes effens verhoog. Die bepaalde SMEn waardes is as volg: RWSF: 16.03 MJ/kg, RDSF: 18.87 MJ/kg, EWSF: 16.22 MJ/kg, EDSF: 19.49 MJ/kg. Ontdopping het geen invloed op skynbare aminosuur bekikbaarheid gehad nie. Skynbare aminosuur beskikbaarheid van ontdopte sonneblomsaad IS me deur hitte-behandeling beinvloed nie, terwyl die van heel sonneblomsaad negatief beinvloed is. Dit beklemtoon die gevare van verswakte proteien kwaliteit as gevolg van oor-prosessering. Geen verskille is opgemerk in terme van massa, voerinname en voeromset verhouding (VOV) tussen die vier produkte gedurende die braaikuikengroeitoets van 42 dae. Alle produkte het maksimale braaikuiken prestasie ondersteun in die aanvangsdieet teen vlakke van 115.0 g/kg. In die afrondingsdieet het RDSF en EDSF optimale braaikuikenprestasie onderhou teen vlakke van 181.5 g/kg, terwyl RWSF en EWSF net t
19

The phosphorus availability of feed phosphates in broilers

Payne, Steven George 03 1900 (has links)
Thesis (MscAgric (Animal Sciences))--University of Stellenbosch, 2005. / Broiler diets are supplemented with feed phosphates to ensure that adequate available phosphorus is provided in the diet to meet the bird’s requirements. These feed phosphates make a considerable contribution to the total available phosphorus in the diet and small differences in their availability may have significant effects on whether the bird’s requirements are met or not. The variation in availability of phosphorus between feed phosphates belonging to different classes and between feed phosphates of the same generic class is well documented.
20

The influence of processing of lupins and canola on apparent metabolizable energy and broiler performance.

Breytenbach, Liesl 12 1900 (has links)
Thesis (MscAgric (Animal Sciences))--University of Stellenbosch, 2005. / The extrusion and dehulling of sweet blue lupins (Lupinus angustifolius, cultivar Wonga) and the expansion of full-fat canola seed were evaluated in terms of their effect on the nitrogen corrected apparent metabolizable energy (AMEn) value and broiler performance.

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