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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.
81

Wall jet model for ceiling fan applications in broiler houses

Blackwell, Neal Elwood January 1985 (has links)
A model was developed to predict velocity profiles of radial wall jets produced by ceiling fans and flowing over broiler chickens. Broilers were modeled by balloons with paper cylinders simulating the necks. Wall jet data was recorded for 91.5, 83.8 and 71.1 cm radius fans that were rated at 220, 160, and 108 W, respectively. Each fan was suspended 2.44 m above the floor and operated at four speeds. Applications of the model include 1) calculation of optimum design specifications for ceiling fan applications in broiler houses and 2) prediction of data for managerial decisions concerning existing ceiling fan applications. Model inputs are the fan radius and the characteristic velocity. The characteristic velocity was defined as the maximum air velocity 30 cm below the blades. The wall jet model was interfaced with a broiler growth model for heat stressed broilers to simulate summer conditions and to predict the additional weight gain due to the wall jet. Also, the wall jet was developed to predict the air velocity near the litter to aid litter management decisions. Ceiling fan applications in the southeast, used in conjunction with the summer model, have the potential of increasing summer broiler production by 10% and decreasing fan energy consumption by 8 to 12%. The model may be used to optimize the benefit to the producer. / Ph. D.
82

Effect of alternatives to antibiotic growth promoters on broiler performance.

Mosoeunyane, Nthoto V. January 2006 (has links)
No abstract available. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
83

Evaluating the efficacy of exogenous composite microbial enzymes in maize-soybean based broiler chicken feeds.

Ngxumeshe, Ayanda Mavis. January 2006 (has links)
This research reported here was carried out to examine alternatives to antibiotic growth promoters as a result of their being banned in the animal feed industry. Four experiments were conducted to evaluate the efficacy of non-medicated feed additives as replacements for antibiotic growth promoters in broiler feeds. The additives used were enzymes (a new thermo-tolerant powder enzyme called TXAP, phytase, lipase and a new phytase enzyme derived from E. coli called phyzyme XP), organic acid (Acid Pak), prebiotic (Bio-Mos®) and probiotic (All-Lac XCL). Mashed maize-soya based feeds were used in all the experiments, which were conducted in litter-floor pens. The first experiment was a dose-response trial. Broilers in eight replicate pens of 50 males and 50 females were fed unsupplemented feeds and five additional feeds containing increasing levels of TXAP, from 0.5 to 2.5 g/kg to 42 d. The second experiment used enzyme TXAP with two different enzymes (phytase and lipase), individually or in combination. Six replicate pens of 50 males and 50 females were fed either unsupplemented feeds or one of six additional feeds treated with TXAP, lipase, phytase , a combination of TXAP and lipase, a combination of TXAP and phytase or a combination of all the three enzymes . This trial continued for 42 d. In the third experiment three types of TXAP (Lot 1, 2 and 3) were used, with fixed levels of xylanase and amylase but varying levels of protease activities (4000, 2000 and 1000 U/kg for Lot 1, 2 and 3, respectively) in combination with phyzyme XP for 35 d. The fourth experiment used mannan-oligosaccharide (Bio-Mos®), organic acid (Acid pak 2x), probiotic (All Lac XCL 5x), individually or in combination and an antibiotic growth promoter (Zinc bacitracin) for 42 d. The chickens in this experiment were challenged with Clostridium perfringens (CP) at 21, 22 and 23 d to determine the efficacy of these additives for replacing antibiotics in hindering the effects of CP on the villus surface area. The dose-response trial did not show any significant improvement in broiler performance with any level of inclusion of enzyme TXAP. The results from this study showed some beneficial effects with the use of enzyme TXAP when fed alone and at a young age. Its use when combined with other enzymes and at later stages of growth needs further investigation. Feed additives in experiment 4 prevented the negative effects of CP as the treated chickens did not have lesions on their villus surfaces. The conditions under which these trials were conducted appeared to be such that little benefit was derived from the use of any of the feed additives used. It is possible that under less-hygienic conditions such as those in commercial operations greater benefits from these additives may be realised. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
84

The effect of highly digestible carbohydrate and protein sources included in pre-starter diets of broilers on their performance

Pretorius, Charne 03 1900 (has links)
Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: In recent years, the aim of the production of broilers became more focused on the increase of the performance of the birds in order to increase profit. To obtain an increased performance with broiler chicks, it is necessary to look at the development of their gastrointestinal tract, the feed requirements and the ability to digest certain nutrients in the period post hatch. Research have shown clear evidence of increased performance of chicks by the inclusion of certain carbohydrate and protein sources in the prestarter diets, but in contrast to this there are also some research that found no significant effects on the performance of broilers when certain carbohydrate and protein sources were included in the pre-starter diet. Therefore, the purpose of this study was to investigate the effect that a product containing specific carbohydrate and protein sources, included in the pre-starter diets of broiler chicks, would have on their performance. It was believed that the products to be tested would result in increased performance of the chicks in the following growth phases. Special emphasis was placed on the average daily gain (ADG), feed intake, cumulative feed intake, feed conversion ratio (FCR), European production efficiency factor (EPEF) and the protein efficiency ratio. Different inclusion levels of the different raw materials were investigated in the first trial. Three raw materials and a control were compared using a summit dilution process at 100:0, 66:34, 50:50, 34:66 and 0:100. Specific production parameters such as ADG total live weight gain, feed intake per week, cumulative feed intake, FCR, EPEF and PER were measured and calculated in order to determine if there were any significant differences between the treatments with the different raw material inclusions on the performance of the chicks. No significant differences (P>0.05) were found between the 13 treatments for the ADG, total live weight gain, feed intake per week, cumulative feed intake, FCR, EPEF and PER. The results therefore indicated that there were no significant differences between the different inclusion levels of the different raw materials and no significant differences for the production parameters for animals receiving diets with various levels of the three raw materials. It is thus concluded that these raw materials can be successfully utilised in pre-starter diets of broiler chicks. The effect of the contribution of sugar to the metabolisable energy (ME) of the raw materials was tested in a commercial grower trial. The three raw materials had inclusion levels leading to supply of either 12% or 18% of the ME in the form of sugar. No significant differences were found between the seven treatments for ADG, total live weight gain, feed intake per week, cumulative feed intake, FCR, EPEF or the PER. It was concluded that the percentage in contribution of sugars between 12 and 18% to the ME of the prestarter diets had no significant effects on the production parameters tested. / AFRIKAANSE OPSOMMING: Met die produksie van braaikuikens word daar deesdae al hoe meer klem gelê op die verhoging van die produksie van die kuikens om dan dus ‘n verhoging in die wins te bewerkstellig. Om hierdie verhoogde produksie by braaikuikens te kan bereik, is dit nodig om na eienskappe van die kuiken soos die ontwikkeling van die spysvertering stelsel, die nutrient- behoeftes van die kuiken en die vermoë om sekere nutriënte te kan verteer in die periode na uitbroei. Sommige navorsing het gewys dat die insluiting van sekere koolhidraat – en proteïen bronne in die voor-aanvangs diëete van braaikuikens, lei tot ‘n positiewe effek op die produksie van die kuikens, waar ander navorsing geen effek gevind het nie. Daarom was die doel van die huidige navorsing gewees om te toets wat die effek van die insluiting in die voor-aanvangs dieet van braaikuikens ‘n sekere produk met ‘n spesifieke koolhidraat –en proteïen bron samestelling op die produksie van die kuikens sal wees in die daaropvolgende fases. Dit was verwag dat die insluiting van hierdie produkte in die voor-aanvangs diëte van braaikuikens ‘n positiewe effek sou hê op die produksie van die kuikens. Spesiale klem was gelê op die parameters soos gemiddelde daaglikse toename (GDT) voer inname, kumulatiewe voer inname, voeromset verhoudings (VOV) Europese produksie doeltreffendheids- faktor (EPEF) en die proteïen doeltreffendheids faktor (PER). Verskillende insluitings vlakke van die verskillende produkte wat getoets is, is in die eerste proef ondersoek. Die drie produkte is deur middel van ‘n piek verdunnings proses by verhoudings van 100:0, 66:34, 50:50, 34:66 en 0:100 met mekaar vergelyk. Spesifieke produksie- parameters soos die GDT, lewende massa, weeklikse voer- inname, kumulatiewe voer- inname, VOV, EPEF en die PER is gemeet. Geen betekenisvolle verskille (P>0.05) was vir die 13 behandelings verkry nie. Die resultate het derhalwe getoon dat daar geen betekenisvolle verskille tussen die verskillende insluitings vlakke van die onderskeie produkte was nie en dat daar geen betekenisvolle tussen die produksieparameters van die kuikens wat die diëte met die verskillende insluitingspeile van die drie roumateriale ontvand het, was nie. Daarom is tot die slotsom gekom dat hierdie roumateriale suksesvol in die vooraanvangsdieet van braaikuikens aangewend kan word. Die effek van die bydrae van die suiker tot die metaboliseerbare energie (ME) van die produkte was in ‘n kommersiële groei proef getoets. Die drie rou materiale was by beide 12- en 18% ingesluit. Geen betekenisvolle verskille (P>0.05) was vir die sewe behandelings vir GDT, lewende massa, weeklikse voer- inname, kumulatiewe voer- inname, VOV, EPEF en PEF verkry nie.
85

The evaluation of larvae of Musca Domestica (common house fly) as protein source for boiler production

Pretorius, Quinton 03 1900 (has links)
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.
86

Effect of supplementing diets with effective microorganisms on intake, growth and carcass characteristics of ross 308 broiler chickens

Mafiri, Matseko Nkele January 2014 (has links)
Thesis (M.Sc. (Animal Production)) -- University of Limpopo, 2014 / Two experiments were conducted to determine the effects of supplementing diets with effective microorganisms on intake, growth and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of supplementing diets with effective microorganisms on performance of unsexed Ross 308 broiler chickens aged one to three weeks. Two hundred unsexed day-old chicks were randomly assigned to five treatments with four replications, each replication having ten birds. A complete randomized design was used. The chickens were fed a grower diet supplemented with 0 (EM0), 30 (EM30), 50 (EM50), 70 (EM70) or 100 (EM100) ml of effective microorganisms per litre of water. Effective microorganism supplementation did not improve (P>0.05) diet and metabolisable energy intakes of the chickens. Effective microorganism supplementation reduced (P<0.05) growth rate and live weight of the chickens. Poorer (P<0.05) feed conversion ratios were observed in chickens supplemented with effective microorganisms. However, effective microorganism supplementation improved (P<0.05) crude protein retention of the chickens. Supplementation with effective microorganisms reduced (P<0.05) mortality rate of the chickens from 10 to 0 %. The second experiment determined the effect of supplementing diets with effective microorganisms on performance of male Ross 308 broiler chickens aged 22 to 42 days. The chickens were randomly allocated to five treatments with four replications, each replication having 10 birds. The chickens aged 21 days, weighing 474 ± 2g, were allocated to the treatments in a complete randomized design. The chickens were fed a grower diet supplemented with 0 (EMM0), 30 (EMM30), 50 (EMM50, 70 (EMM70) or 100 (EMM100) ml of effective microorganisms per litre of water. Effective microorganism supplementation did not improve (P>0.05) intake, DM digestibility, metabolisable energy, feed conversion ratio, fat pad weight and meat sensory attributes of the chickens. Effective microorganism supplementation reduced (P<0.05) growth rate, live weight and carcass weight of the chickens. However, effective microorganism supplementation improved (P<0.05) crude protein retention and crude protein content of meat of the chickens. Supplementation with effective microorganisms reduced (P<0.05) mortality of the chickens from 5 to 0 %. v It is concluded that effective microorganism supplementation to the diets of Ross 308 broiler chickens reduced growth rate and live weight of the chickens. However, effective microorganism supplementation improved crude protein retention and crude protein content of the meat of broiler chickens. Supplementation with effective microorganisms reduced mortality of the chickens to zero.
87

The effects of dietary lysine, crude protein, energy and feed allocation on broiler breeder hen performance.

Patel, Jamila. 20 October 2014 (has links)
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.
88

Atividade antimicrobiana de ácidos orgânicos e compostos clorados sobre micro-organismos patogênicos em carne de frango / Antimicrobial activity of organic acids and chlorinated compounds over pathogenic microorganisms in poultry meat

Zabot, Sandra 30 March 2016 (has links)
O cenário atual da produção avícola brasileira é definido pela alta produtividade motivada pelas exportações para mercados com elevados níveis de exigência sanitária. O trabalho objetivou avaliar a eficácia de compostos clorados (dióxido de cloro, dicloro e tricloro) e ácidos orgânicos (ácidos cítrico, lático e peracético) na redução da contaminação de carne de frango por Salmonella spp., mesófilos e enterobactérias. Foram isoladas 102 cepas de Salmonella spp. de carcaças de frango no período de junho a setembro de 2014. As cepas foram identificadas por PCR. Determinou-se a concentração inibitória mínima (CIM) dos compostos para as cepas padrões de S. Typhimurium, S. Enteritidis e S. Heidelberg. A CIM dos ácidos lático e peracético (20 e 10 g/L) foi aplicada em cepas de Salmonella spp. isoladas do frigorífico. A CIM dos compostos ácido lático e dicloro foi aplicada em água de chiller contaminada com Salmonella (109 UFC/mL) e foi determinada a contagem de Salmonella presente na água. Coxas e sobrecoxas de frango foram contaminadas com S. Heidelberg (109 UFC/mL) e foram aplicados os compostos dicloro (60 mg/L), ácido lático (20 g/L) e hipoclorito de sódio (5,0 e 0,5 mg/L). Na identificação por PCR, 93,1% das cepas foram identificadas como Salmonella spp. Para o dicloro a CIM foi de 60 mg/L por 15 minutos para S. Heidelberg e 60 mg/L por 20 minutos para S. Enteritidis. O ácido lático apresentou CIM de 5 g/L por 10 minutos para S. Enteritidis, 10 g/L por 15 minutos para S. Typhimurium e 20 g/L por 20 minutos para S. Heidelberg. Para o ácido peracético, as CIMs foram de 10 g/L por 10 minutos para S. Typhimurium e S. Heidelberg e 10 g/L por 20 minutos para S. Enteritidis. Para o ácido cítrico, as CIMs foram de 10 g/L por 10 minutos para S. Typhimurium e S. Enteritidis e 25 g/L por 20 minutos para S. Heidelberg. Nas cepas de Salmonella isoladas, o ácido lático inibiu 97,89% das cepas e o peracético inibiu 100% das cepas. Na água de chiller contaminada os compostos reduziram o crescimento das cepas padrões. Quando aplicados em carne de frango contaminada, houve redução de Salmonella spp. de 1,06 log10 UFC/g em relação ao controle positivo com o hipoclorito de sódio a 5,0 mg/L, 0,97 log10 UFC/g com o dicloro e 0,56 log10 UFC/g com o hipoclorito de sódio a 0,5 mg/L. Para mesófilos a redução observada foi de 0,90 log10 UFC/g em relação ao controle positivo com o hipoclorito de sódio a 5,0 mg/L, 0,90 log10 UFC/g com o dicloro e não havendo redução com o hipoclorito de sódio a 0,5 mg/L. Para enterobactérias a redução foi de 1,0 log10 UFC/g em relação ao controle positivo com o hipoclorito de sódio a 5,0 mg/L, 0,79 log10 UFC/g com o dicloro e 0,22 log10 UFC/g com o hipoclorito de sódio a 0,5 mg/L. O ácido lático inibiu o crescimento bacteriano dos micro-organismos testados. Os dados obtidos reforçam a necessidade de discussões para regulamentar o uso de coadjuvantes de tecnologia no abate de aves. / The current scenario of the Brazilian poultry production is defined by high productivity motivated by exports to markets with elevated levels of sanitary requirement. The work aimed to evaluate the efficacy of chlorinated compounds (chlorine dioxide, dichloro and trichloro) and organic acids (citric, lactic and peracetic acids) in reducing the contamination of poultry by Salmonella spp., mesophiles and enterobacteriaceae. Were isolated 102 strains Salmonella spp. poultry carcass from June to September 2014. Strains were identified by PCR. Was determined the minimum inhibitory concentration (MIC) of antimicrobial compounds for the standard strains of S. Typhimurium, S. Enteritidis and S. Heidelberg. MIC of lactic acid and peracetic acid (20 to 10 g/L) was applied in strains of Salmonella spp. isolated from the slaughter. The MIC of the compounds lactic acid and sodium dichloro was applied in contaminated chiller water with Salmonella (109 CFU/mL) and this was determined Salmonella count in water. Thighs and drumsticks poultry were contaminated with S. Heidelberg (109 UFC/mL) and were applied dichloro (60 mg/L), lactic acid (20 g/L) and sodium hypochlorite (5,0 and 0,5 mg/L) compounds. In the identification by PCR, 93,1% of the strains were identified as Salmonella. For sodium dichloro the MIC was 60 mg/L for 15 minutes to S. Heidelberg and 60 mg/L for 20 minutes for S. Enteritidis. Lactic acid presented MIC of the 5 g/L for 10 minutes to S. Enteritidis 10 g/L for 15 minutes to S. Typhimurium and 20 g/L for 20 minutes to S. Heidelberg. For peracetic acid, MICs were 10 g/L for 10 minutes to S. Typhimurium and S. Heidelberg and 10 g/L for 20 minutes to S. Enteritidis. To citric acid, MICs were 10 g/L for 10 minutes to S. Typhimurium and S. Enteritidis and 25 g/L for 20 minutes to S. Heidelberg. In the isolated Salmonella strains, lactic acid inhibited 97,89% of the strains and peracetic inhibited 100% of the strains. In contaminated chiller water, the compounds reduced the growth of standards strains. When applied to contaminated poultry meat, there was a reduction of Salmonella spp. 1,06 log10 CFU/g relative to the positive control with the use of sodium hypochlorite at 5,0 mg/L, 0,97 log10 CFU/g with dichloro and 0,56 log10 CFU/g with sodium hypochlorite 0,5 mg/L. For mesophiles reduction observed was 0,90 log10 CFU/g relative to the positive control with the use of sodium hypochlorite at 5,0 mg/L, 0,83 log10 CFU/g with dichloro and there isn´t reduction with hypochlorite with sodium 0,5 mg/L. For enterobacteriaceae reduction was 1,0 log10 CFU/g relative to the positive control with the use of sodium hypochlorite at 5,0 mg/L, 0,79 log10 CFU/g with dichloro and 0,22 log10 CFU/g with sodium hypochlorite at 0,5 mg/L. Lactic acid inhibit growth of the microorganisms tested. The data supports the discussions to regulate the use of the technology coadjuvants in the slaughter of poultry.
89

Mapeamento fino de qtls e polimorfismos de genes candidatos associados ao crescimento no cromossomo 1 da galinha /

Boschiero, Clarissa, 1979- January 2009 (has links)
Orientador: Ana Silvia Alves Meira Tavares Moura / Banca: Luiz Lehmann Coutinho / Banca: Mônica Corrêa Ledur / Banca: Millor Fernandes do Rosário / Banca: José Roberto Sartori / Resumo: A partir de resultados de um estudo anterior, no qual foram mapeados QTLs para características de peso vivo, peso do coração e pulmões no GGA1, foi definida uma região no intervalo entre os marcadores ADL0234 e LEI0071, abrangendo 82,3 cM. Foram avaliadas três famílias de meios-irmãos paternos que compreendiam sete famílias de irmãos completos, num total de 652 F2 para as características: peso vivo aos 35 e 41 dias de idade, pesos do coração e pulmões e rendimentos de coração e pulmões. Os genótipos de seis marcadores microssatélites foram adicionados aos dez utilizados anteriormente. O mapa de ligação obtido da região compreendeu 110,8 cM com espaçamento médio entre os marcadores de 7,4 cM. Na análise de F2, em um único intervalo (LEI0146-LEI0174), compreendendo 28,8 cM, foram mapeados QTLs para todas as características estudadas, com exceção dos rendimentos de coração e pulmões. Neste intervalo estão localizados o gene IGF1 e o centrômero do cromossomo. A adição de seis marcadores confirmou os QTLs mapeados anteriormente, porém alguns em diferentes posições. A análise de meios-irmãos paternos indicou que os principais QTLs estavam segregando em apenas uma das famílias (7716), na qual cinco QTLs foram mapeados. Na análise de meios-irmãos maternos, duas famílias segregaram QTLs tanto na análise Individual como na Conjunta (7810 e 7971). As diferentes análises permitiram selecionar dois casais F1, que devem ser o alvo dos próximos estudos. Este estudo restringiu a busca por genes candidatos responsáveis pelas características de interesse a uma região de 28,8 cM (9,82 Mb) no GGA1. / Abstract: Based on the results from a previous study, in which QTL for body weight, heart and lungs weights and heart and lungs percentages were mapped to GGA1, a region was defined between markers ADL0234 and LEI0071, spanning 82.3 cM. Three paternal half-sib families, comprising seven full-sib families, totaling 652 F2 were evaluated for body weight at 35 and 41 days of age, heart and lungs weights and heart and lungs yields. Genotypes of six microsatellite markers were added to those of ten previously used. The linkage map of this region spanned 110.8 cM, with average spacing of 7.4 cM between markers. In a single interval (LEI0146-LEI0174), comprising 28.8 cM, QTLs for all traits, except for heart and lungs yields were mapped in the F2 analysis. In this same interval the IGF1 gene, and the chromosome centromere, are located. The use of six additional markers confirmed the same QTLs mapped previously, but some of them, in different positions. The paternal half-sib analysis indicated that the main QTLs were segregating in one of the families only (7716), in which five QTLs were mapped. In the maternal half-sib analysis, two families segregated QTLs both, in the across and within families analyses (7810 and 7971). These analyses allowed the selection of two F1 couples to be the target for future studies. This study restricted the search for candidate genes responsible for the traits of interest to a region of 28.8 cM (9.82 Mb) in GGA1. / Doutor
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Ocorrência de carne pálida e características de qualidade de carne de frangos de corte /

Takahashi, Sabrina Endo, 1978- January 2007 (has links)
Orientador: Ariel Antonio Mendes / Banca: Hirasilva Borba Alves de Souza / Banca: Carmen Josefina Contreras Castilho / Banca: Roberto de Oliveira Roça / Banca: Edivaldo Antonio Garcia / Resumo: O objetivo do presente estudo foi verificar a ocorrência da carne pálida em diferentes linhagens de frango de corte e também avaliar as demais características de qualidade de carne. Foram utilizados 1440 pintos de corte de um dia, sexados, distribuídos segundo um delineamento inteiramente casualizado em esquema fatorial 3 x 2, com três linhagens (Avian48, Cobb e Hubbard) e dois sexos, com quatro repetições de 60 aves cada, totalizando 24 parcelas experimentais. As aves foram criadas sob as mesmas condições de manejo e alimentação. Aos 35, 42 e 49 dias de idade, foram retiradas 48 aves no total em cada abate para avaliação da ocorrência de carne pálida e determinações das características de qualidade da carne do peito, como pH, cor, desnaturação protéica, perda de exsudato, capacidade de retenção e absorção de água, perdas por cozimento e força de cisalhamento. Os resultados foram submetidos à Análise de Variância e, posteriormente, ao teste de comparação de médias de Tukey para as variáveis com diferença estatística significativa, utilizando o procedimento GLM (General Linear Models) do programa estatístico SAS (SAS Institute, 1996). Nas condições em que foi realizado este experimento, as diferentes linhagens não apresentaram diferenças com relação às características de qualidade de carne. Os machos apresentaram um valor de pH maior em comparação com as fêmeas em todas as idades estudadas. Com relação à coloração da carne, em todas as idades, as carnes de peito não apresentaram valores superiores à L*49,0, que os classificariam como pálidas, ou seja, a cor variou de normal à escura independente da linhagem, indicando, desta forma, que a linhagem não influenciou a ocorrência de carne pálida nem as demais características de qualidade. / Abstract: The objective of this study was to verify the occurrence of pale meat in different commercial strains of broiler chickens and also to evaluate the other characteristics of meat quality. We used 1440 one day old chicks, male and female, distributed in a completely randomized design in an factorial 3 x 2, with 3 strains (Avian48, Cobb e Hubbard) and 2 genders, with four repetitions of 60 chickens each, in a total of 24 experimental parcels. The chickens were raised under the same handling and feeding conditions. When the chickens were 35, 42 and 49 days old, we removed 48 of them in total in each slaughter for evaluating the occurrence of pale meat and determining the characteristics of their breast meat quality, such as pH, color, protein denaturation, exsudate loss, capacity of water retention and absorption, losses for cooking and shearing strength. The results were submitted to the Variation Analysis and afterwards to the Tukey average comparison test for the variables with significant statistic difference, using the GLM (General Linear Models) procedure of the statistics program SAS (SAS Institute, 1996). Under this experiment's conditions, the different lineages didn't present any differences related to the characteristics of the meat quality. The males presented a higher pH value comparing to the females in all the ages studied. About the meat coloring, in all ages, the breast meat didn't present values higher than L*49,0, which would be considered pale that means that the color changed from normal to dark independently of the lineage, indicating that the lineage didn't influence the occurrence of pale meat and the other quality characteristics. / Doutor

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