Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011. / Includes bibliography. / 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 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.

No description available.

Broiler production is an important animal production enterprise with potential to make high returns. Increasing feed efficiency and early body weight gain has always been a top priority in the broiler industry. The general objective of broiler nutrition is to maximise production performance and profitability . Nutrition is of major importance in raising chicken, and feed is a major input in poultry production systems, accounting for over 60% of total production costs in commercial poultry sector Renkema (1992). The cost of feed is therefore often a constraint especially in developing countries. For instance, Onyenokwe (1994) observed that high cost of feed ingredients in many African countries has caused many poultry farmers to abandon the industry. The continued rise in feed prices is due to competition for some of the ingredients with human e.g. sorghum, wheat and maize. Broiler farmers are therefore forced to use combinations of feed ingredients of low cost to obtain savings and avoid any further loss of profits. It is therefore important to give special attention to feed and feeding since the rate of feed consumption increases rapidly with advancing age of the birds and good nutrition is reflected in the bird's performance and its products. The profitability of a broiler enterprise depends on the efficient conversion of feed to meat. Broilers have the ability to convert the feeds into meat with a high efficiency. For instance Morris and Njuru (1990) reported that broilers have much higher daily rates of protein deposition than layer chicken strains. This implies that fast-growing strains would require greater daily protein intakes than slow-growing ones. In the past, the major criteria for assessing the performance of broilers has been growth rate and feed conversion ratio (FeR). Diet specifications and feeding programmes have been aimed at maximising these two parameters whereby overall flock performance is calculated based on the total weight of chicken produced from total feed deliveries. With the new developments in understanding of nutritional factors affecting broiler growth and carcass composition, it is now possible to apply sophisticated and yet efficient approaches to feeding broilers. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2005.

This study was conducted to investigate the effects of varying levels of dietary lysine and feed allocation, on the performance of female broiler breeders. In trial 1, 900 Cobb breeders from 26 to 45 weeks of age were used. The first four treatments had a fixed level of lysine throughout the experimental period, with 1200, 1070, 930 and 800 mg Lysine/bird/day and the last two treatments had their levels of lysine changed every two weeks, with treatment five started off with 1200 mg lysine/bird/day followed by a gradual decrease up to 975 mg lysine/bird/day at 45 week old, while treatment six started with the lowest level of lysine, 800 mg/bird/day and at 45 week old the intake was 1025 mg/bird/day. The rations provided 1900KJ ME/ day, the birds received 160 g of feed/day. Dietary lysine did not affect body weight, egg production, or egg composition. There were no significant differences in age at 50%, or peak production. Birds receiving 1070 and 1025 mg lysine/bird.day had a slightly, but not significantly, higher production in the current study. Birds receiving 1200 mg lysine/bird.day had the highest body weight and the lowest egg production. In trial 2, 900 broiler breeder hens were used. Protein intake and feed allocation were changed for each treatment at 26, 38 and 50 weeks and ending at 60 weeks. Birds on T1 were fed a constant CP content (145 g protein/kg) but a decreasing feed allocation (175 to 145 g/d). Those on T2 had a constant feed allocation (160 g/d) and a decreasing CP (166 to 124 g/kg) while those on T3 had varying levels of protein (166, 124 and 166 g/kg) and feed allocation (160, 160, 145 g/d). Mean cumulative protein intakes were 5.2, 5.3 and 4.8 kg/bird and mean energy intakes were 417, 412 and 402 MJ/bird for T1, T2 and T3 respectively. Body weights differed significantly at the end of the trial (P<0.05) with T2 showing the highest weight gain. However, egg production, egg weight and egg output were not affected by treatment. These breeders did not benefit from the additional protein and energy provided in the first and second periods by T1 and T2 (vs. T3), nor did they benefit from the additional energy provided in the final ten weeks of production by T2. / M.Sc.Agric. University of KwaZulu-Natal, Pietermaritzburg 2013.

Thesis (MScFoodSc)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Modern consumers are health conscious and are shifting towards more naturally produced products such as free range chicken. Commercial broiler strains are not suitable for free range rearing and an alternative genotype is needed that will serve the South African market with the acceptable meat quality as a broiler. The objective of this study was to investigate the effect of production system (free range and intensive reared) and genotype (Broiler (COBB™), Ross 308 X Potchefstroom Koekoek hybrid and Potchefstroom Koekoek) on chicken meat quality. This was quantified on the morphological, physical (pH, colour, drip and cooking loss, water holding capacity and tenderness), chemical composition (moisture, protein, fat, ash contents and fatty acid profile), sensory quality and consumer preference of various chicken meat portions. The results of this study indicate that genotype had a more pronounced effect than production system on the morphological and growth properties of chicken meat, as well as on the sensory characteristics and consumer preference. The broilers had the best (P ≤ 0.05) feed conversion ratio (FCR), highest average daily gain (ADG) and European production efficiency factor (EPEF), followed by the Hybrid and then the Potchefstroom Koekoek. For each genotype, the free range chickens produced heavier (P ≤ 0.05) live weights than intensively reared chickens. Despite the poorer growth performance and efficiency of the medium growing Hybrid birds, they had less mortality and fewer leg disorders than the broiler. Additional to these factors, the Hybrid Free Range had higher thigh, drumstick and wing yields (P ≤ 0.05) than the broiler. When investigating the correlation between the chemical and sensory data, it was observed that the Hybrid scored significantly higher (P ≤ 0.05) in both flavour and aroma than the Broiler and Koekoek genotypes for both production systems. For colour, pH and polyunsaturated to saturated fatty acid ratio (PUFA:SFA), the effect of production system was more pronounced than the effect of genotype. Rearing chickens in a free range environment increased the PUFA:SFA ratio (P ≤ 0.05), making it beneficial to human health. Free range rearing resulted in lower muscle pHu (P ≤ 0.05), darker (L* value) (P ≤ 0.05), less red and yellow (a* and b* value) (P ≤ 0.05) chicken meat. It also influenced the chemical composition in different carcass portions; for example, a lower fat content in the thigh and higher protein in the breast of the Broiler. Correlation with the sensory results indicated that juiciness, tenderness, chicken aroma and chicken flavour are the main drivers of liking for consumer’s preference towards chicken meat. The consumers predominantly preferred the Hybrid (P ≤ 0.05) in a blind tasting session, but when information was given on the production system of a chicken product, the consumers lean more towards a free range reared product than an intensive reared product. This indicates that consumer perception plays an immense role in consumer decision making. Cluster analysis was also performed to ascertain whether the consumers differed in their degree of liking of the intrinsic character of the respective chicken samples. Three different clusters of consumers were identified: 1) Consumers that prefer free range reared chicken meat, 2) Consumers that prefer intensively reared chicken meat, 3) Consumers that prefer both free range and intensive reared chicken meat. In conclusion, the Hybrid seems to be a viable option for free range production systems in South Africa, without negatively affecting the overall quality of the meat or consumer acceptance. / AFRIKAANSE OPSOMMING: Moderne verbruikers is baie meer gesonheidsbewus en verkies meer natuurlik geproduseerde produkte soos vrylopende (free range) hoenders. Die kommersiële braaikuiken is nie geskik vir vrylopende produksie nie en `n ander genotipe word benodig wat die Suid-Afrikaanse mark sal kan voorsien met aanvaarbare vleiskwaliteit vergelykbaar met dié van die braaikuiken. Die doel van hierdie navorsing was om die effek van produksiestelsel (vrylopend en intensief) en genotipe (braaikuiken (COBB™), Potchefstroom Koekoek en Ross 308 X Potchefstroom Koekoek kruising) op die morfologiese, fisiese (pH, kleur, drip- en kookverlies, waterhouvermoë en taaiheid), chemiese samestelling (vog-, proteïen-, vet-, asinhoud en vetsuurprofiel), sensoriese kwaliteit en verbruikersaanvaarbaarheid van verskeie hoender vleis porsies te bepaal. Hierdie navorsing het getoon dat genotipe `n groter invloed gehad het as produksiestelsel op die groei en morfologiese eienskappe van die hoenders, asook op die sensoriese eienskappe en verbruikersaanvaarbaarheid. Die braaikuiken, gevolg deur die Ross X Koekoek kruising en dan die Koekoek, het die beste (P ≤ 0.05) voeromsetverhouding (FCR), gemiddelde daaglikse toename (GDT) en Europese produksie effektiwiteitsfaktor (EPEF) getoon. Vir elke genotipe het die vrylopende hoenders swaarder (P ≤ 0.05) lewende massa by slag getoon. Ten spyte daarvan dat die Ross X Koekoek kruising swakker groei en effektiwiteitsresultate getoon het, het hulle laer mortaliteite en minder been breuke en beserings as die braaikuiken gehad. Die Ross X Koekoek kruising wat vrylopend groot gemaak is, het ook swaarder dy, boud en vlerkie massa (P ≤ 0.05) as die braaikuiken getoon. Die navorsing het ook getoon dat kleur, pH en die poli-onversadigde tot versadigde vetsuur verhouding (PUFA:SFA) meer beïnvloed is deur die effek van produksiestelsel as genotipe. Die hoenders wat in ʼn vrylopende omgewing grootgemaak is se PUFA:SFA verhouding is hoër as dié van intensiewe boerdery, wat dit voordelig maak vir menslike gesondheid. Vrylopende hoenders se vleis is donkerder (L*) (P ≤ 0.05) en het ook laer rooi, geel (a* en b*) en pH (P ≤ 0.05) waardes getoon. Produksiestelsel effek het ook variërende chemiese waardes in verskillende karkas porsies tot gevolg gehad: ʼn laer vetinhoud is gevind in die dy en ʼn hoër proteïeninhoud in die borsies van die braaikuikens wat vrylopend grootgemaak is. Korrelasies met die sensoriese data het ook getoon dat sappigheid, taaiheid en hoendervleis geur die grootste dryfvere is in verbruikersaanvaarbaarheid. Tydens die verbruikerstoetse waar die verbruikers die gaar hoendervleis blind geproe het, het die verbruikers oor die algemeen meer gehou van die Ross X Koekoek kruising in vergelyking met die ander hoender genotipes (P ≤ 0.05), maar sodra inligting oor die verskillende produksiestelsels gegee is, het die verbruikers aangedui dat hulle hoenders wat vrylopend groot gemaak is, verkies. Dit dui daarop dat persepsies ʼn baie belangrike rol speel in die verbruiker se finale besluitnemingsproses. Statistiese segmentasietegnieke is ook op die data uitgevoer ten einde te bepaal of verbruikers in groepe verdeel kan word wat betref hul voorkeur van die sensoriese of intrinsieke eienskappe van die hoenderprodukte. Drie verskillende groepe is geïdentifiseer, nl. verbruikers wat 1) vrylopende hoender vleis verkies; 2) intensiewe hoender vleis verkies; 3) beide vrylopende en intensiewe hoender vleis verkies. In die lig van bogenoemde resultate wil dit voorkom of kruisteling tussen die gewone braaikuiken en die Potchefstroom Koekoek ʼn moontlike opsie is vir die Suid-Afrikaanse vryloop hoenderbedryf. Hierdeur word daar van vrylopende produksie stelsels gebruik gemaak sonder om die vleiskwaliteit of gebruikers aanvaarbaarheid negatief te beïnvloed.

Thesis (M. Tech.(Agriculture: Animal Production)) - Central University of technology, Free State, 2012 / A 42-day feeding trial involving 180 day old broiler chicks was carried out at Glen Agric Institute ARC poultry section to study the effects of whole hatchery waste meal (WHWM) as an alternative in broiler diets. In this study whole hatchery waste meal (WHHW) replaced fish meal (FM), protein for protein, in broiler diets at 0, 10, 20, and 30% levels. One hundred and eighty broiler chickens were grouped, 45 birds per treatment which were further replicated 3 times (15 birds per replicate) in a completely randomized design. Feed and water supply were offered to birds ad libitum while standard management practices were meticulously adopted. Samples of the two test ingredients were sent to a lab for chemical analysis and the results indicated that FM had higher content of crude protein (73.18%) while that of WHWM was 4226. The calcium phosphorus ratio was 16.6:1 for WHWM as against 1.5:1 in the FM. The results also indicated a higher content of Ash% and Ether extract for WHWM (18.12) and (23.94) respectively. The higher ash content could be due to the high content of eggshell at the time of processing. At the end of the feeding trial broiler performance, blood, carcass characteristics and the economic benefit of using WHWM in broiler diets were determined. Blood and meat samples were collected and sent to the pathology laboratory at the University of the Free State, Bloemfontein for hematological and meat characteristics analysis. Results for broiler performance showed that broilers fed diet 2 had highest values for feed intake (118.25g/bird/day), weight gain (50.16g/bird/day) and daily protein intake (29.08g/bird/day) while those fed with diet 3 were superior in the efficiency of feed conversion (2.31). The highest value of abdominal fat 1.12% was observed in birds fed diet 2. The highest live mass was observed in birds fed diets containing no WHWM (2.83), while non significant difference were observed in live mass of birds fed diet 1, 3 and 4. Broilers fed control diet had highest mean values for eviscerated weight (2.20kg) and dressing percentage (77.86%). Blood samples were sent for analysis of White blood cells (WBC), Red blood cells (RBC) and Haemoglobin (HGB), Hematogrit (HCT), Mean corpuscular volume (MCV), Mean corpuscular haemoglobin (MCH) and Mean corpuscular haemoglobin concentration (MCHC). The results showed marginal variations in blood parameters. White blood cell counts were higher for birds fed control diet (519.59 x 103/1) than those fed WHWM (484.93 X 103/1). Non significant differences (P > 0.05) were observed on the HGB of all treatment groups including the control group. RBC counts of T1-T3 were not significantly different from each other but statistically significantly different from T4 (30% WHWM). The highest value of 2.67 106/ mm3 was observed in birds fed a higher level of WHWM. High RBC and HGB counts in the birds fed WHWM are an indicative of higher oxygen carrying capacity. The HCT and MCH results showed nonsignificant differences between T1, T3 and T4, except T2 which was significantly different from the other treatment groups. The MCV values for T1-T4 were 132.58, 126.47, 129.15 and 128.15 10'15L respectively. The highest and lowest values were recorded on T1 and T2 respectively. The feed costs decreased with an increase in the level of WHWM in broiler diets. The lowest feed cost/kg weight gain of R8.69 recorded for broilers fed on diet three. This agrees with several studies which documented the use of hatching waste in poultry diet as means of reducing feed cost (Babiker et al 1991; Abiola, 1999; Abiola, 2000; Abiola and Onunkwor 2004). It can be concluded that 10% of FM can be replaced with WHWM in broiler diets without adverse effects on growth, hematological and carcass traits.

Thesis (MScAgric)--Stellenbosch University, 2008. / ENGLISH ABSTRACT: Different substances were evaluated and compared to an antibiotic, in terms of their effect on nitrogen - and amino acid digestibilities. Two digestibility trials and one performance trial were conducted. Trials one and two apparent nitrogen (AND)- and amino acid (AAD) digestibilities were determined from digesta collected at the terminal ileum (ileal digestibility method). In Trial 3 the substances were evaluated in terms of their potential to improve production performance. Broilers were fed a maizesoya based diet throughout the three trails. In the first trial, garlic and a commercial prebiotic (Bio-Mos®), were tested and compared in terms of AND and AAD, to an antibiotic (doxycyclin, Doxyvete-SOS). A starter and finisher diet were fed as either mash or pellets. The garlic was included at 8g/kg, 13g/kg and 18g/kg to the starter and finisher diets. Bio-Mos® was added at 1g/kg, 2g/kg and 3g/kg to the starter diet, and 0.5g/kg, 1g/kg and 1.5g/kg to the finisher diet. The doxycyclin was added at 0.3 g/kg. None of the treatments had any beneficial effects in terms of AND. Feeding a pellet seem to have some negative effects in terms of AND. In general most of the treatments did not show any improvement in AAD at any determination period (day 21, 28 or 35). At day 21 and day 35, the mash diet supplemented with 18g/kg garlic had a negative effect on AAD, when compared to the negative and positive control. It doesn’t seem that feeding either a mash or a pellet had an influence on the effects exerted by the different treatments. In the second trial the influence of Bio-Mos®, a blend of organic acids, probiotics and electrolytes (Acid-Pak 4-way®) and a medium-chain triglyceride (MCT) were evaluated and compared in terms of AAD and AND, to the effect of an antibiotic, doxycyclin. The starter and finisher diets were fed as a mash. Bio-Mos® was included at 1g/kg, 2g/kg, and 3g/kg in the starter diet, and at 0.5g/kg, 1g/kg, 1.5g/kg in the finisher diet, respectively. Acid-Pak 4-way® was included at 0.4g/kg, 1g/kg and 1.6g/kg for both the starter and finisher diets. Medium-chain triglycerides (MCT) were allocated at 3g/kg, 3.6g/kg, 4.2g/kg for the starter diet, and 2.1g/kg, 2.7g/kg and 3.4g/kg for the finisher diet. An antibiotic, doxycyclin, was included at 0.3 g/kg. With AND, no treatment had any significant effect for the entire experimental period. At day 21, the treatment supplemented with MCT (3.4g/kg) had the most significant beneficial effect on AAD, when compared to the negative- and positive controls, as it increased AAD for the majority of the amino acids. The treatment with Acid-Pak 4-way® (1g/kg) had the most significant negative effect on AAD when compared to the positive control. At day 28, the treatments with Bio-Mos® (0.5g/kg and 1.5g/kg) and Acid-Pak 4-way® (0.4g/kg) had the most significant beneficial effect on AAD when compared to the positive control. It increased AAD for more than half of the 17 amino acids evaluated. The treatment supplemented with MCT (2.7g/kg) has shown the most significant negative effect on AAD, when compared to the positive control. In the third trial the effect of Bio-Mos®, Acid-Pak 4-way® and MCT on production performance was evaluated, and compared to the effects of the presence or absence of doxycyclin. Body weight (BW), body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) were measured. The starter and finisher diets were fed as a mash. Bio-Mos®, MCT and Acid-Pak 4-way® were included at 3.0g/kg, 4.2g/kg and 1.6g/kg, respectively in the starter and finisher diets. Birds were weighed (per pen) on arrival and on days 7, 14, 21, 28, 35. Feed intake (FI) per pen was measured at days 7, 14, 21, 28 and 35, and mortality was recorded daily. In terms of BWG, Acid-Pak 4-way® had a higher BWG, when compared to the negative control, Bio-Mos® and MCT. It can be concluded that Bio-Mos®, Acid-Pak 4-way®, as well as MCT can be a possible alternatives to antibiotic supplementation. These three treatments did not necessary prove to be more effective than antibiotics, but are definitely competitive alternatives. / AFRIKAANSE OPSOMMING: Verskillende behandelings is geëvalueer en vergelyk met ‘n antimikrobiese produk, in terme van hul uitwerking op stikstof - en aminosuur verteerbaarhede. Twee verteringstudies en produksieprestasie studie is uitgevoer. In die eerste twee studies is die skynbare stikstof (AND)- en aminosuur (AAD) verteringskoöeffisiënte bepaal deur gebruik te maak van digesta wat by die terminale ileum ingesamel is (ileale verteringsmetode). In die derde studie is die produksie prestasie van braaikuikens op ‘n gebalanseerde metaboliseerbare energie (AME) rantsoen, soos beïnvloed deur die verskillende behandelings, geëvalueer. In die eerste studie is knoffel en ‘n kommersiële prebiotikum (Bio-Mos®) geëvalueer en met ‘n antibiotikum (doksisiklien, Doxyveto-SOS) in terme van AND en AAD vergelyk. Beginner- en afrondingsrantsoene is as ‘n meel of pille gevoer. Die knoffel is teen 8g/kg, 13g/kg en 18g/kg in die rantsoen ingesluit. Bio-Mos® is teen 1g/kg, 2g/kg en 3g/kg in die beginner rantsoen en teen 0.5g/kg, 1g/kg en 1.5g/kg in die afrondingsrantsoen, ingesluit. Die antibiotikum is teen 0.3g/kg in beide rantsoene ingesluit. Geen van die behandelings het enige positiewe invloed op AND gehad nie. Deur ‘n verpilde rantsoen te voer het sekere negatiewe invloed op AND gehad. Oor die algemeen het geen behandelings enige positiewe invloed op AAD gehad nie. Op dag 21 en 35 het die insluiting van knoffel teen 18g/kg in ’n meel rantsoen ’n negatiewe invloed op AAD gehad, wanneer dit met die negatiewe- en positiewe kontroles vergelyk is. Dit blyk nie dat om ‘n pil of meel te voer enige invloed op die invloede van die verskillende behandelings gehad het nie. In die tweede studie is Bio-Mos®, ‘n organiese suur (Acid-Pak 4-way®) en ‘n medium-ketting trigliseried (MCT) geëvalueer en met ‘n antbiotikum, doksisiklien (Doxyveto-SOS) in terme van AND en AAD, vergelyk. Beginner- en afrondingsrantsoene is gevoer as ‘n meel. Bio-Mos® is teen 1g/kg, 2g/kg, and 3g/kg in die beginner rantsoen en teen 0.5g/kg, 1g/kg, 1.5g/kg in die afrondingsrantsoen, ingesluit. Acid-Pak 4-way® is teen 0.4g/kg, 1g/kg en 1.6g/kg vir die beginner –en afrondingsrantsoene ingesluit. Die MCT is teen 3g/kg, 3.6g/kg, 4.2g/kg in die beginner rantsoen en teen 2.1g/kg, 2.7g/kg en 3.4g/kg in die afrondingsrantsoen ingesluit. Die antibiotikum is ingesluit teen 0.3g/kg. Geen behandelings het enige betekenisvolle invloed in terme van AND gehad nie. Op dag 21 het MCT (3.4g/kg), in vergelyking met die negatiewe- en positiewe kontrole, die grootste positiewe invloed op AAD gehad. Acid-Pak 4-way® (1g/kg) het, in vergelyking met die positiewe kontrole, ‘n positiewe invloed gehad op AAD. Op dag 28, het Bio-Mos® (0.5g/kg en 1.5g/kg) en Acid-Pak 4-way® (0.4g/kg) die grootste positiewe invloed op AAD gehad. Die behandeling met MCT (2.7g/kg) het die mees negatiewe invloed op AAD gehad. In die derde studie is die insluiting van Bio-Mos®, Acid-Pak 4-way® en MCT getoets om die invloed op braaikuiken produksie prestasie te evalueer, en te vergelyk met die invloed van die insluiting of afwesigheid van ‘n antibiotikum. Liggaamsmassa (BW), liggaamsmassa toename (BWG), voerinname (FI) en voeromsetverhouding (FCR) is gemeet. Beginner- en afrondings rantsoene is gevoer as ‘n meel. Bio-Mos®, MCT en Acid-Pak 4-way® is onderskeidelik teen 3.0g/kg, 4,2g/kg en 1.6g/kg in die rantsoen ingesluit. Die kuikens is met aankoms (per hok) geweeg, asook op dae 7, 14, 21, 28, 35. Voerinname per hok is gemeet op dae 7, 14, 21, 28 en 35. Mortaliteite is daagliks aangeteken. Die insluiting van Acid-Pak 4-way® het in vergelyking met die negatiewe kontrole, Bio-Mos® en MCT insluiting ‘n hoër BWG tot gevolg gehad. Die gevolgtrekking wat gemaak kan word is dat Bio-Mos®, Acid-Pak 4-way® en MCT gebruik kan word as ‘n moontlike alternatief vir antibiotika insluiting. Hierdie drie behandelings was nie noodwending meer effektief as die antibiotika nie, maar het wel bewys dat dit kompeterende alternatiewe is.

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.

Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011. / Includes bibliography. / ENGLISH ABSTRACT: A growth and digestibility trial was conducted comparing the effect of an experimental enzyme at three different inclusions. A negative control containing no enzyme additions and a positive control containing a proven commercial enzyme were compared in a maize-soybean diet noting the performance of broilers and the digestibility of the grower feed. The commercial enzyme was a granular product with a xylanase activity of 38114.29 nkat/g and the second enzyme (ABO374) was a liquid experimental product with a xylanase activity of 1426.86 nkat/ml. Five diets were used i.e. control basal diet without enzyme supplementation (negative control), basal diet supplemented with the commercial enzyme (positive control) and three basal diets supplemented with the test enzyme at various inclusion levels (ABO 50, ABO 100 and ABO 200). The positive control was supplemented with 200 g/ton of the commercial enzyme; ABO 50 was supplemented with ABO374 at an inclusion level of 2671 ml/ton, ABO 100 with 5342 ml/ton and ABO 200 with 10684 ml/ton. Supplementation with the test enzyme (ABO 50) significantly improved BW at 23 days of age by 4.6 % (1107.4 g vs 960.96 g) and at 37 days of age by 3.2 % (2311.75 g vs 2237.81 g) over the negative control. Body weight gain for the total period of the trial was significantly improved by 3.24 % (64.32 g/bird/day vs 62.24 g/bird/day) the test enzyme supplementation (ABO 50) when compared to the negative control. During the starter phase, test enzyme supplementation (ABO 50) led to an improvement of 4.58 % (1.25 vs 1.31) in FCR in comparison with the negative control. The FCR for the total trial obtained by the test enzyme supplementation was significantly lower than the FCR obtained by the positive control. The highest EPER obtained for this trail was by the test enzyme supplemented diets and this was significantly higher than the EPER obtained by the positive control. It is clear from this growth trial that the test enzyme (ABO374) at an inclusion level of 2671 ml/ton outperformed the commercial enzyme and that it has the potential to improve the production performance of broilers on a maizeSBM based diet. The total tract digestibility method and total collection method was used to conduct the digestibility trial. The total tract digestibility method measures the difference between the amounts of each nutrient consumed from the amounts of each nutrient excreted in faeces. Only apparent digestibilities are reported for the digestibility trial. Apparent digestibility does not take the endogenous protein fraction in the faeces into account. The endogenous protein fraction is derived from digestive enzymes and proteins from the intestinal walls that are secreted into the digestive tract. The grower negative control, positive control, ABO 50, ABO 100 and ABO 200 diets used in the production trial were also used in the digestibility trial. Supplementation with the test enzyme showed no significant improvements on the apparent digestibility of dry matter, organic material, ash, crude protein, metabolisable energy or crude fibre. No significant improvements in the apparent digestibility of the amino acids (threonine, arginine, valine, lysine, methionine, cysteine and isoleucine) were noticed either and thus the digestibility of the grower feed were not influenced by the addition of enzymes due to the supplementation of the test enzyme ABO374. Pelletisation of the grower diets could have lead to the inactivation of the enzyme due to the high temperature at which pelletisation takes place. Another possible reason why enzyme supplementation did not increase nutrient digestibility, may be that the breakdown of non-starch polysaccharides by the enzymes led to an increase in the concentration of oligosaccharides in the small intestine of the birds, thus leading to the decrease in nutrient absorption Key words: body weight, body weight gain, feed conversion ratio, European production efficiency ratio, maize, soybean meal, apparent digestibility, dry matter, organic material, ash, crude protein, metabolisable energy, crude fibre, xylanase, pellitisation. / AFRIKAANSE OPSOMMING: ‘n Groei en vertering studie was uitgevoer om die effek van ‘n eksperimentele ensiem wat teen drie verskillende insluitingsvlakke by ‘n basale dieët bygevoeg is te vergelyk met ‘n negatiewe kontrole wat geen ensiem bevat het nie en met ‘n positiewe kontrole wat ‘n kommersiële ensiem bevat in ‘n mielesojaboon oliekoek dieët op die produksie vermoë van braaikuikens en die verteerbaarheid van die groei voer. Die kommersiële ensiem was ‘n granulêre produk met ‘n xylanase aktiwiteit van 38114.29 nkat/g en die eksperimentele ensiem (ABO374) was ‘n vloeistof produk met ‘n xylanase aktiwiteit van 1426.86 nkat/ml. Vyf diëte was gebruik nl. ‘n basale dieët met geen ensiem byvoeging (negatiewe kontrole), basale dieët met die byvoeging van die kommersiële ensiem (positiewe kontrole) en drie basale diëte wat met die byvoeging van die eksperimentele ensiem teen drie verskillende insluitings vlakke (ABO 50, ABO 100 and ABO 200). Die kommersiële ensiem was by die positiewe kontrole bygevoeg met ‘n insluitings vlak van 200 g/ton, ABO374 was bygevoeg by ABO 50 met ‘n insluitings vlak van 2671 ml/ton, ABO 100 met 5342 ml/ton en ABO 200 met 10684 ml/ton. Die byvoeging van die eksperimentele ensiem (ABO 50) het gelei tot die betekenisvolle verbetering van die liggaamsmassa van die voëls by die ouderdom van 23 dae met 4.6 % (1107.4 g teenoor 960.96 g) en by die ouderdom van 37 dae met 3.2 % (2311.75 g teenoor 2237.81 g) teenoor die negatiewe kontrole. Liggaams massa toename vir die hele periode van die studie was betekenisvol verhoog met 3.24 % (64.32 g/kuiken/dag teenoor 62.24 g/kuilen/dag) met die byvoeging van die eksperimentele ensiem (ABO374) teenoor die negatiewe kontrole. Voeromset verhouding was betekenisvol verbeter met 4.58 % (1.25 teenoor 1.31) toe die kommersiële ensiem bygevoeg was teenoor die negatiewe kontrole. Die hoogste europese produksie effektiwiteits verhouding wat verkry is vir die hele studie periode is deur die byvoeging van die eksperimentele ensiem (ABO374). Hierdie groei studie dui dus duidelik aan dat die gebruik van die eksperimentele ensiem (ABO374) baie beter resultate as die kommersiële ensiem opgelewer het teen ‘n insluitings vlak van 2671 ml/ton, dus het ABO374 die potensiaal om die produksie potensiaal van braaikuikens op ‘n mielie-sojaboonoliekoek dieët te verbeter. Die totale spysverteringskanaal verteerbaarheid metode was gebruik om die verteerbaarheid studie uit te voer. Die totale spysverteringskanaal verteerbaarheid metode meet die verskil tussen die nutriënt inhoud van die voer en die nutriënt inhoud van die mis. Slegs die skynbare verteerbaarheid van nutriënte word vir hierdie verteerbaarheidstudie gerapporteer. Skynbare verteerbaarheid sluit nie die endogene proteïenfraksie wat afkomstig is van verteringsensieme of die proteïene afkomstig vanaf die spysverteringskanaal se intestinale wande af in nie. Die negatiewe kontrole, positiewe kontrole, ABO 50, ABO 100 en ABO 200 groei diëte gebruik in die produksie studie is gebruik vir die verteringsstudie. Die byvoeging van die eksperimentele ensiem het geen betekenisvolle resultate opgelewer ten opsigte van droë materiaal, organiese material, as, ru-proteïen, ru-vesel of metaboliseerbare energie nie. Daar was ook geen betekenisvolle resultate opgelewer wanneer die eksperimentele ensiem bygevoeg was nie ten opsigte van die verteerbaarheid vir aminosure (treonien, arginien, valien, metionien, sisteïen en isoleosien) nie en dus is die verteerbaarheid van die groeivoer glad nie beïnvloed deur die byvoeging van die eksperimentele ensiem nie. Die verpilling van die groei voer mag dalk gelei het tot die inaktivering van die eksperimentele ensiem deur dat dit blootgestel was aan hoë temperature. ‘n Ander moontlike rede vir die mislukking van die ensiem kon gewees het dat die afbreking van die nie-stysel polisakkariedes deur die ensiem kon gelei het tot die verhoging van die oligosakkariede konsentrasie in die laer spysverterings kanaal en dus kon dit lei tot ‘n verhoogde deurvloeitempo, gevolg deur ‘n afname in die absorpsie van nutriënte. Sleutel woorde: Liggaamsmassa, liggaamsmassa toename, voeromsetverhouding Europese produksie effektiwiteits verhouding, mielie, sojaboonoliekoek, skynbare verteerbaarheid, droëmaterial, organiesematerial, as, ru-proteïen, ru-vesel, metaboliseerbare energie, verpilling.

The objective of the study was to evaluate the effect of an exogenous multi-blend enzyme ( -glucanase and xylanase) on the performance of the broiler chickens and laying hens fed diets based on wheat and barley. Experiments were conducted on a flock of broilers and two flocks of laying hens. In both cases feed and water were provided ad libitum. The enzyme effect of enzyme addition on the broiler performance involved 2080 day-old male and female chicks in 48 pens, allocated one of four dietary treatments (0, 50, 100 or 200g/ton enzyme supplementation), to 35 days of age. On day 35, ten birds from each treatment were sacrificed for the analysis of the digestive organs weight (gizzards and livers). The trial was divided into two phases: a starter (1 to 21 d) and grower (22 to 35 d). Feed consumption was measured weekly and birds were also weighed weekly. The investigation of enzyme effect in laying hen diets involved 896 birds for each specific period. Each replicate consisted of four cages (four birds per cage) with a common feeder; 16 hens/pen of 56 pens. Eggs were weighed three times a week, feed consumption weekly and birds every weeks. The addition of a multi-blend enzyme significantly improve body weight, body weight gain, food intake, and feed conversion ratio for both sexes (P<0.05) in broiler chickens. There was a significant improvement in egg production in laying hens (P<0.05). Egg weight and egg mass were not significantly improved. Wheat and barley have cell wall components (arabinoxylans and -glucans respectively) which have a negative effect on the nutritive value of these feeds and therefore performance in poultry fed diets based on these ingredients. Addition of an exogenous multi-blend enzyme( -glucanase and xylanase) could help reduce these effects and improve performance and digestibility values in poultry. The null hypothesis was there will be no difference between supplemented and un-supplemented diets based on wheat and barley in performance of poultry. The results of this study suggest that the inclusion of 50 g/ton enzyme helps improve poultry performance, especially in young birds. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.