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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.
51

The Acute and Chronic Effects of a Cyclic Heat Stress on 24 to 28 Week Old Laying Hens on Performance, Egg Quality, Apparent Metabolizable Energy, and Blood Chemistry

Barrett, Nathaniel W. 02 November 2016 (has links)
Commercial laying hens are heavily selected for increased egg production, but little selection has occurred for resistance to extreme temperatures. The objective of the experiment was to determine the effects of a daily cyclic heat stress (HS) on performance, body temperature, egg quality, nitrogen corrected apparent metabolizable energy, and blood chemistry in laying hens at acute and chronic time points. In total, 407 pure line laying hen pullets (18 wk) were sourced from Hy-Line International and housed individually for the duration of the experiment. Feed intake, egg production, and body weights were significantly decreased while egg weight and feed efficiency increased due to HS exposure. All egg quality parameters except yolk weight were decreased by HS exposure, including Haugh unit, eggshell and albumen weights. Egg yolk weights were increased over the first 2 wk of HS before falling. Blood chemistry was affected by HS resulting in respiratory alkalosis likely caused by increased respiration and evaporative cooling. There was a decrease in the PCO2, an increase in pH and a reduction in iCa in the blood within 4 to 6 hours of HS when compared to pre-HS levels. The data indicate that the hens were negatively affected by HS and the response was different for acute and chronic time points. At the acute time point the changes to the hen's physiology were caused by altered blood chemistry, but after chronic exposure, the low feed intake seemed to influence the responses. / Master of Science
52

<b>THE IMPACTS OF HOUSING DESIGN ON LAYING HEN BEHAVIOR: A COMPARATIVE ASSESSMENT OF TWO CAGE-FREE HOUSING SYSTEMS</b>

Gideon Seun Ajibola (19225747) 27 July 2024 (has links)
<p dir="ltr">Due to increasing legislative and societal demand for humane egg production, an increased production of cage-free eggs is inevitable. Past research has focused on the impact of cage-free housing systems (CFS) on laying hens' performance, health, and space use; however, limited studies have examined the impacts of CFS on the behavioral activities of laying hens, particularly in single-tier floor systems in the U.S. Broadly, this research examined the influence of two housing systems on the behavior of laying hens as they age. Specifically, the study aimed to provide information on how dissimilar cage-free systems meet the behavioral needs of laying hens. </p><p dir="ltr">Two hundred pullets were randomly assigned to either a single-tier floor room (SFR) or a modified multi-tier aviary room (MAR) at 17 weeks of age (WOA), where they remained until 85 WOA. Starting at 55 WOA, thirty focal birds were marked with non-toxic markers for individual identification in each room. The behavior of the birds was recorded continuously over two consecutive days during the mid-laying (55 WOA) and late-laying (85 WOA) phases. The behavioral expressions of the focal birds were annotated using 10-min continuous sampling at 5 time points (10 minutes after lights-on (TOD 1), 4 hr after lights-on (TOD 2), 8hr after lights-on (TOD 3), 12 hr after lights-on (TOD 4), and 10 minutes before lights-off (TOD 5)). At each of these 5 time points, 4 birds were randomly selected for observation. Behavior duration and frequency data were analyzed using PROC GLIMMIX in SAS 9.4, with the main effects of housing system (HS), age, and time of day (TOD). Descriptive statistics were used to present the behavioral time budgets of marked and unmarked birds in MAR and SFR. Further, the behaviors performed in different spatial zones (areas within each room) were presented as the percentage of observed time laying hens spent engaged in a specific behavior over the total time at a particular spatial zone. </p><p dir="ltr">Birds in MAR and SFR spent most of the observed time perching at all ages. The birds (marked and unmarked) performed environmental pecking and foraging for the highest percentage of time in the litter area of SFR and MAR. Similarly, the percentage of time the birds (marked and unmarked) spent preening and performing OCB (wing flapping, stretching, and feather-ruffling) was highest when they occupied the litter zone of MAR and SFR. Housing system influenced the time that both marked and unmarked birds spent performing foraging and environmental pecking (EP) such that marked and unmarked birds in SFR spent more time engaged in these behaviors than marked and unmarked birds in MAR (Marked: SFR vs. MAR, P = 0.043; Unmarked: SFR vs. MAR, P = 0.002). Further, marked and unmarked birds in SFR exhibited a higher frequency of EP than birds in MAR (Marked: SFR vs. MAR, P = 0.02; Unmarked: SFR vs. MAR, P < 0.001). The frequency of locomotion (standing and walking) activity differed between SFR and MAR birds. Birds (marked and unmarked) stood more frequently in SFR than in MAR (Marked: SFR vs. MAR, P = 0.046; Unmarked: SFR vs. MAR, P < 0.001). Further, SFR birds had a higher walking frequency than MAR birds (Marked: P = 0.003; Unmarked: P = 0.02). Birds (marked and unmarked) in MAR perched more frequently than SFR birds (Marked: SFR vs. MAR, P < 0.001; Unmarked: SFR vs. MAR, P = 0.01); however, unmarked birds preened more frequently in SFR than in MAR (P < 0.001). Regarding time of day, both marked and unmarked birds exhibited higher preening frequency 10 mins after lights-on (TOD 1) than at other times of day (P < 0.001). Similarly, marked birds perched for a longer duration early in the morning (TOD 1) and late at night (TOD 5), than at TOD 2 and TOD 3 (P < 0.001). </p><p dir="ltr">This study revealed that MAR and SFR may differ in how they accommodate the behavioral needs of laying hens, with hen activity levels varying between the two types of housing systems. Further research is needed to understand the implications of behavioral outcomes for the welfare of laying hens in different types of CFS.</p>
53

Role of a precision biotic and a protease fed alone and in combination to Dekalb White laying hens at peak production phase

Rodewald, ElsiAnna 10 May 2024 (has links) (PDF)
A precision biotic (PB) in standard and reduced CP diets, and a protease (PRO) used alone and in combination with PB in the reduced CP diet were evaluated. Effects on performance, digestibility, and blood biomarkers were determined in Dekalb White hens from 24 to 42 weeks of age. Nine diets were fed: 1) a standard diet with a 17.5% formulated CP level (T1); 2) T1 with 500ppm PB (T2); 3) T1 with 700ppm PB (T3); 4) a reduced CP diet with a 15.5% formulated CP level (T4); 5) T4 with 500ppm PB (T5); 6) T4 with 700ppm PB (T6); 7) T4 with 33g/MT PRO (T7); 8) T4 with 33g/MT PRO and 500ppm PB (T8); and 9) T4 with 33g/MT PRO and 700ppm PB (T9). There were no overall differences for feed conversion, but the response of T9 over time suggests longer periods may result in improved feed conversion.
54

Effect of amino acids and vitamin D3 on performance and biological responses in poultry

Wen, Jinlei 08 June 2018 (has links)
As productive performance is improved by breed selection, amino acid requirements may change to support this higher performance in poultry. The first objective of this dissertation was to update the valine and tryptophan requirement of small-framed laying hens and the lysine requirement of young broilers using empirical dose-response methods. The tryptophan requirement was estimated as 155.8 mg/d for egg mass, 153.2 mg/d for egg production and 140.4 mg/d for feed conversion ratio using a linear broken line model. For valine, the requirement was highest for egg mass, 597.3 mg/d, followed by egg production, 591.9 mg/d and feed conversion ratio (FCR), 500.5 mg/d. The lysine requirement of young chicks was estimated by conducting four short term experiments from 1 to 3, 3 to 5, 5 to 8 and 8 to 11 days of age, respectively. The lysine requirement from 1 to 3, 3 to 5 and 5 to 8 days of age were not able to be estimated as no dose response was observed on growth performance most likely due to an overestimation of the lysine requirement. Digestible lysine requirement from 8 to 11 days of age was 1.057%, 1.050% and 1.016% based on body weight gain, FCR and pectoralis major weight using a linear broken line model, respectively. In addition to determining amino acid requirements, research was conducted to develop a new bacterial protein meal for use in laying hens diets. The data suggested that diets containing 7.5% of the bacterial protein meal was able to at least maintain egg production in laying hens, but 15% bacterial protein meal resulted in reduced performance. The second objective of this dissertation was to investigate the effects of various concentrations of dietary vitamin D3 on pullet and laying hen performance, eggshell quality and bone health in laying hens. Pullets/hens were randomly assigned to five dietary treatments containing vitamin D3 from 1,681 to 68,348 IU/kg diet from day of hatch until 68 weeks of age. These data suggested that dietary vitamin D3 fed at 68,348 IU/kg resulted in reduced egg production, but vitamin D from 8,348 to 35,014 IU/kg diet maintained egg production, increased egg vitamin D content in a dose dependent manner, and generally increased both eggshell quality and pullet and hen bone mineral status. / Ph. D. / The goal of the poultry industry is to increase the efficiency of meat and egg production. To achieve this goal, laying hens with higher egg production and broilers with faster growth rates are genetically selected over time. By breed selection, laying hens are able to produce 2-3 additional eggs every year. The body weight of a broiler chicken raised today is approximately four times greater than one raised to the same age in 1958. This Increased egg production and body growth requires a higher nutrient intake, especially amino acids, to support protein production. One objective of this dissertation was to update the requirement of three amino acids (valine, tryptophan and lysine) in poultry production to provide current and accurate information to poultry producers. Valine, tryptophan and lysine are essential amino acids that cannot be synthesized by poultry in sufficient quanities and needs to be ingested from the diet. Three experiments were conducted to determine the valine and tryptophan requirement in laying hens and lysine requirement in broilers. The results of the current experiment show that a laying hen require at least 156 mg tryptophan and 597 mg valine per day to maximize egg production from 41 to 60 weeks of age. The broiler chicks need to ingest rations containing at least 1.06% lysine to support growth from 8 to 11 days of age. Bacterial protein meal is a feed ingredient that has been proposed for use in poultry diets. It is usually produced via the fermentation process by converting various substrates such as methane, methanol, or agriculture by-products into protein-rich biomass. The advantage of using bacterial protein meal in the poultry industry is to decrease feed cost and alleviate the demand on croplands. A novel bacterial protein meal, generated from waste water purification, was evaluated as a feedstuff for laying hens. Two levels of bacterial protein meal, 7.5 or 15%, were added to a regular laying hen diet to replace soybean. The results indicated that replacing soybean meal with 7.5% bacterial protein meal was a feasible solution for egg production but a 15% inclusion rate may result in a decreased egg production. During egg production, bone structural health can be reduced as laying hens age. This loss of bone structural health is due to the loss of bone mineral content, especially calcium and phosphorus, as laying hens produce the calcium rich eggshell. With age, decreased bone mineral mass will induce a higher probability of bone structural failure. Vitamin D plays an important role on calcium absorption and bone mineral deposition. In addition to benefits to skeletal health, the addition of vitamin D₃ in the diet will result in increased vitamin D₃ content in eggs used for human consumption. An experiment was conducted to evaluate the use of high concentrations of vitamin D to increase egg vitamin D content, improve eggshell quatility and increase hen skeletal health. The data suggest that adding vitamin D₃ from 8,300 to 35,000 IU/kg diet will increase egg viatimn D content, and generally improve eggshell and bone quality; however, adding vitamin D₃ at 68,000 IU/kg diet resulted in negative effects on pullet growth and subsequent egg production of adult hens.
55

INTERACTION OF DIETARY SUPPLEMENTS OF ORGANIC TRACE MINERALS AND PHYTASE ON GROWTH PERFORMANCE AND MINERAL METABOLISM OF REPLACEMENT PULLETS

Mañón, Alfredo 01 January 2015 (has links)
Effects of dietary supplementation with low levels of organic sources of trace minerals in place of normal levels of their inorganic salts and phytase on growth performance and mineral metabolism were evaluated in two studies using pullets of white and brown shell laying strains. The organic sources were proteinates of copper, iron, manganese and zinc and selenium yeast. A corn-soybean meal diet was fed alone, plus inorganic minerals or plus organic minerals, and with or without phytase in a 3 x 2 factorial arrangement. Twelve groups of 16 pullets, 2 weeks old, were used per treatment. Compared with inorganic minerals, feeding no mineral supplement or organic minerals significantly (P<0.05) decreased manure Cu, Fe and Zn for white pullets and Cu, Fe, Mn and Zn for brown pullets. Dietary phytase significantly reduced manure Fe, P and Ca for white pullets and Fe, Mn, Zn, P and Ca for brown pullets. Adding phytase to diets containing inorganic minerals reduced manure Zn concentration for white pullets and manure Fe, Mn, Zn, P and Ca concentrations for brown pullets. These studies indicate manure levels of trace minerals can be decreased by using low levels of organic mineral supplements and phytase in pullet diets.
56

The Adoption of Ergonomic Innovations for Injury Prevention : Examples from the building construction and health care industries

Glimskär, Bo January 2014 (has links)
A good work environment is important for the individual, for industry and for society. The work environment research has, predominantly, targeted identification of problems and the measurement of the size of these problems. Innovations to reduce the incidence of musculoskeletal disorder, MSD, have been introduced in different branches of industry, but with limited success. Few of the ergonomic innovations developed for the building and construction industry have reached a sufficient level of adoption. Ergonomic innovations in the health care sector are of an incremental character and seem to have similar problems of adoption as the ones in the building and construction industry. Three examples of ergonomic innovation are examined in the thesis: a glue spreader for floor layers a four-wheel walker with a lifting device a sonographer’s scanning support device The studies show that an ergonomic innovation is not adopted for prevention of occupational injury unless the innovation also has other relative advantages apart from the ergonomic ones. For the group who already has sustained an injury, it is enough that the ergonomic problems are solved, while the other, symptom-free group, requires other advantages in order to adopt the innovation; increased production economy seems to be the most prominent potential advantage. / <p>QC 20150114</p>
57

Détermination du champ d'application du système d'alimentation séquentielle chez les poules pondeuses / Determination of the limits of the sequential feeding system in laying hens

Traineau, Maxime 29 April 2014 (has links)
L’alimentation séquentielle (AS) consiste à distribuer de manière cyclique deux aliments différents dont la combinaison permet des apports nutritionnels adaptés. L’objectif de la thèse était d’évaluer la robustesse et les limites de ce système. Trois expérimentations ont étéréalisées. Les questions portaient sur la variation de la composition en matières premières des régimes, la capacité d’adaptation des poules à des situations de déséquilibre alimentaire et de stress thermique et enfin la modulation au cours de la journée des apports en énergie et en protéines. Un travail de méta-analyse apportait des réponses sur la régulation de l’ingestion chez les poules pondeuses ainsi que sur l’impact de la nature des ingérés sur les performances de ponte et de croissance. Les expérimentations (Ex.1, 2, 3) ont permis de mettre en évidence la possibilité de distribuer d’autres céréales (blé et/ou maïs broyé, fibres insolubles) à la place du blé entier distribué dans la fraction du matin. L’ingestion totale inférieure par rapport à une alimentation continue (Ex. 1 et 2) et un niveau de production équivalent permettent d’améliorer l’IC des poules en AS par rapport à des poules alimentée de façon classique. Les poules semblent capables de réguler leur ingestion sur le niveau d’énergie de l’aliment mais pas sur son niveau de protéines dans les conditions étudiées (méta-analyse, Ex. 2). Cependant, les apports en énergie doivent se concentrer dans la fraction du matin afin d’obtenir les meilleures performances en AS tandis que les apports protéiques doivent soit être concentrés dans la fraction de l’après midi soit continus au cours de la journée (Ex. 3). Ces connaissances sur l’AS doivent encore être complétées afin de pouvoir utiliser ce système d’alimentation en élevage néanmoins l’AS est prometteur en terme d’économies de ressources. / Sequential feeding (SF) consists in splitting the nutrients into two different diets. The goal of this thesis was to explore the limits of this feeding system. Three experiments were performed. The major questions go on utilization of other feedstuffs, capacity of hens to adapt their feed intake on unbalanced diet and hot temperatures and responses to modulation of energy and protein supplies. A meta-analysis gave responses on the regulation of feed intake and the impact on nutrient intake on laying and growth performances in laying hens. Experiments (Ex.1, 2, 3) shown off the possibility to substitute whole wheat with other cereals or feedstuffs (ground wheat and/or corn, insoluble fiber) in the morning fraction. Lower total feed intake in SF compared to continuous feeding (Ex. 1 et 2) and same laying performances improved the FCR. Laying hens were able to fit their feed intake on energy in the diet but not on protein content (meta-analysis, Ex. 2). Nevertheless, energy supplies had to be given in the morning fraction while protein could be given concentrate in the afternoon or throughout the day (Ex. 3). Knowledge on SF has to be completed in order to use this feeding system in commercial conditions. SF can help sparing resources and improve the on farm economical efficiency.
58

Desempenho, crescimento, qualidade do ovo, composição corporal e características reprodutivas e ósseas de poedeiras submetidas a diferentes programas nutricionais / Performance, growth, egg quality, body composition, bone and reproductive characteristics of hens fed different nutritional programs

Santos, Andréa Luciana dos 15 February 2008 (has links)
Essa pesquisa teve como objetivos avaliar o desempenho, perfil do crescimento, qualidade do ovo, composição corporal e características ósseas e reprodutivas de poedeiras alimentadas com diferentes programas nutricionais, no período de 1 dia até 72 semanas de idade. Foram utilizadas 1656 aves distribuídas em um delineamento inteiramente casualizado em esquema fatorial 3x2 com os fatores: Programas nutricionais (P1 - 95% das exigências nutricionais, P2 - 100% das exigências nutricionais e P3 - 105% das exigências nutricionais preconizadas pelo Manual Hy-Line) e variedades da linhagem Hy-Line (W36 e Brown), totalizando seis tratamentos com seis repetições de 46 aves cada. Para obter as curvas de crescimento utilizou-se a equação de Gompertz e modelo matemático multifásico. O programa P3 proporcionou melhor ganho de peso na fase de cria (0 - 6 semanas) e, similarmente os programas P2 e P3 na fase de recria (7 - 17 semanas). Em ambas as fases (cria e recria), o consumo de ração não foi influenciado pelos programas nutricionais. No entanto, as aves da variedade Brown apresentaram maior consumo de ração e maior ganho de peso em relação às aves da variedade W36. Verificou-se que durante a fase de produção, os programas nutricionais não afetaram a produção de ovos, peso dos ovos e conversão alimentar. Como esperado, as poedeiras Brown apresentaram maiores valores para as características consumo de ração e produção, peso e massa de ovos em relação às poedeiras W36. As características de qualidade interna dos ovos (porcentagens de gema e albúmen, unidade Haugh e índice gema), de qualidade externa dos ovos (porcentagem de casca, espessura de casca e densidade aparente do ovo), ósseas (resistência à quebra, concentrações de cálcio e fósforo e densitometria) e reprodutivas (peso e diâmetro dos folículos ovarianos e peso e comprimento dos segmentos do oviduto) não foram influenciadas pelos programas nutricionais, no período de 18 a 72 semanas de idade. As poedeiras W36 apresentaram maiores valores para o percentual de gema, resistência óssea à quebra e densitometria óssea. Por outro lado, as poedeiras Brown apresentaram maiores valores para o percentual de albúmen, espessura da casca, densidade aparente dos ovos, peso e comprimento do magno, útero e vagina. A taxa máxima de crescimento do peso vivo e dos nutrientes na carcaça (proteína, gordura, cinzas e água) ocorre em idades diferentes. No geral, a equação de Gompertz proporcionou melhor ajuste dos dados em relação ao modelo matemático multifásico. Conclui-se que o programa P3 é o mais indicado para a fase de cria e que o programa P2 atende as exigências nutricionais para as fases de recria e produção. As variedades W36 e Brown apresentam diferentes perfis de desempenho, crescimento, resistência óssea, reprodutivo e de qualidade dos ovos. / This study was carried out to evaluate the performance, growth profile, egg quality, body composition, and bone and reproductive characteristics of hens fed different nutritional programs from day-one to 72 weeks of age. 1656 birds were randomly assigned in a factorial scheme 3x2: nutritional programs (P1 - 95% of the requirements, P2 - 100% of the requirements, and P3 - 105% of the requirements according to Hy-Line Manual) and Hy-Line strains (W36 and Brown), resulting six treatments with six replicates of 46 birds each. To obtain the growth curves was used the equation of Gompertz and multiphase mathematical model. P3 program provided better weight gain in the starter phase (0 - 6 weeks) and, similarly, P2 and P3 programs for the grower phase (7 - 17 weeks). In both phases (starter and grower), feed intake was not influenced by the nutritional programs. However, the Brown pullets showed higher feed intake and weight gain than W36 pullets. It was verified, during the production phase, that egg production, egg weight, and feed conversion were not affected by the nutritional programs. As expected, the Brown hens showed higher values for feed intake, egg production, egg weight, and egg mass than W36 hens. Egg internal (yolk and albumen percentages, Haugh unit, and yolk index), egg external (shell percent, shell thickness, and egg specific gravity), bone (breaking force resistance, calcium and phosphorus concentrations, and bone densitometry), and reproductive characteristics (weight and length of follicles ovarian and of the oviduct segments) were not influenced by the nutritional programs, from 18 to 72 weeks of age. W36 hens showed higher values for yolk percent, bone breaking force resistance, and bone densitometry. On the other hand, Brown hens showed higher values for albumen percent, shell thickness, egg specific gravity, weight and length of magnum, uterus, and vagina. The maximum rates of body growth and nutrients of carcass (protein, fat, ash and water) occurs in different ages. In general, the equation of Gompertz provided better adjust of the data than multiphase mathematical model. It was concluded that the P3 program is indicated for starter phase and P2 program is able to support the nutritional requirements for grower and production phases. The varieties W36 and Brown show different performance, growth, bone strength, reproductive and egg quality profiles.
59

Caracterização tipológica e bioclimática da avicultura de postura no Estado de São Paulo &#150; um estudo de caso / Typology and bioclimatic characterization of laying hen housing in the State of São Paulo &#150; a case study

Telatin Junior, Aurélio 31 May 2007 (has links)
Este trabalho objetivou a caracterização dos ambientes de criação de aves poedeiras, de granjas comerciais no Estado de São Paulo, sob o ponto de vista bioclimático, tipológico e do bem-estar do trabalhador. Na primeira etapa foram selecionadas 6 granjas. Nestas granjas, escolhidas por critérios pré-estabelecidos, foram realizadas análises do ambiente de produção, com medições em loco, da concentração de amônia, do nível de pressão sonora, da temperatura e da umidade relativa do ar, e também, por meio de um levantamento quanti-qualitativo, a satisfação do trabalhador. Na segunda etapa, foi realizado um estudo de caso, com a análise bioclimática de dois sistemas de produção, sendo um piramidal 2x2 com cobertura de telhas cerâmicas e o outro piramidal 2x3 com cobertura de telhas de cimento-amianto. Como resultados foram caracterizados diferentes sistemas de produção de ovos: 1) piramidal 2x2 e 2x3, que ainda se diferenciam quanto a largura do aviário, manejo, automatização e tipo de cobertura, além de poderem ser suspensos ou diretamente no solo; 2) vertical, obrigatoriamente automatizado e com uso de ventilação mecânica, e 3) horizontal, pouco utilizado pela baixa densidade que oferece. Concluiu-se que a concentração de amônia não atingiu o nível de insalubridade indicado pela norma regulamentar NR15 (20ppm). Os maiores níveis foram encontrados nos aviários verticais, e os níveis mais baixos nos aviários suspensos. O nível de pressão sonora, embora citado por funcionários como sendo incômodo, esteve abaixo do limite de insalubridade indicado pela norma regulamentar NR15 para 8 horas de serviço (85dB). O setor de produção de ovos é pouco exigente quanto à escolaridade e experiência funcional, podendo ser considerado uma boa oportunidade para o primeiro emprego. Foi predominante o número de jovens com menos de 20 anos, do sexo masculino, com baixa incidência de doenças trabalhando nos aviários. Houve baixo índice de rejeição ao ambiente de trabalho. O setor não oferece, tampouco exige a utilização de EPI. Os sistemas avaliados na segunda etapa, quanto ao nível de pressão sonora e concentração de amônia foram considerados salubres. A avaliação bioclimática mostrou que aviários com telha cerâmica apresentaram melhores resultados. / This work aimed to characterize the rearing system environment of laying hens, of the commercial farms in the State of São Paulo, in relation to the typology, bioclimatology, and the stockmanship well-being. In the first stage, 6 farms were selected. In these farms, chosen for the previous settle criteria, was carried out analyzes of the environment by means measurements of ammonia concentration, sound pressure level, temperature and relative humidity of air and the thermal comfort index in the facilitie and also, by means of poll between the workers, was analyzed the stockmanship welfare. In the second stage, a case study was achieve, making bioclimatic analysis of two rearing systems: battery cages (pyramidal format) with 4 rows in 2 levels with ceramic roofing tiles and the pyramidal format with 6 rows in 3 levels with asbestos roofing tiles. As results, was found facilities that can be suspended or in the ground with multi tiered cages (battery cages arranged back-to-back in a pyramidal format) that differs in width, handling, automation and type of covering; 2) multi tiered in vertical arrangement (obligatorily automatic and with mechanic ventilation), and 3) single horizontal rows, poorly utilized in function of its low density. The ammonia concentration did not reach the insalubrities level, being, also below the indicated level by the NR15 (20ppm). The biggest levels were found in farms with vertical arrangements of cages and the lowest levels was observed in the farms with suspended facilities. The sound pressure level, even so cited for employees as being bothering, was inside that limits of salubrious indicated by the technique norm to eight hours of labor (85dB). The egg production sector makes few exigencies in relation to the level of schoolarity and experience, being able to be considered a good chance for the first job. The observed predominance working into facilities was of young people with less than twenty years old, male, with good health. There was low index of repulse of work environment. The sector didn&#39;t offer exigency for the IPE use. At the second stage, none of the two studied systems was considered unhealthy concerning the ammonia concentration and sound pressure level and the thermal comfort index. The bioclimatic estimate, showed that those system covered by ceramic roofing tiles had better results.
60

Produção e qualidade de ovos em poedeiras semi-pesadas: efeitos do consumo de energia e óleo / Production and egg quality semi-heavy laying hens: effects of energy consumption and oil

Silva, Amadeu Benedito Piozzi da 04 July 2001 (has links)
O presente experimento foi realizado no aviário da Faculdade de Medicina Veterinária e Zootecnia da Universidade Estadual Paulista do Campus de Botucatu. Foram utilizadas 288 aves da linhagem Hisex Brown, em produção, com 30 semanas de idade no início do experimento, divididas em nove tratamentos com quatro repetições cada, num esquema fatorial 3X3, sendo três níveis de energia metabolizável fornecidos por ave/dia (280, 300 e 320 kcal) e três diferentes consumos de óleo por ave/dia (0,00; 0.75 e 1,50 g). O consumo diário de ração foi restrito a 115, 110 e 105 g para obtenção dos níveis desejados de energia metabolizável e óleo. As rações foram balanceadas para que todas as aves recebessem diariamente 18 g de proteína bruta, 4,2 g de Cálcio, 0,66 g de Fósforo Total, 0,40 g de Metionina, 0,73 g de Metionina + Cistina e 0,83 g de Lisina. Não foi constatada diferença estatística (P>0,05) para produção (%), massa (g/ave/dia), peso médio (g) e gravidade específica dos ovos bem como para umidade, percentagem de gordura, proteína e cinzas do albume e da gema. Houve efeito do consumo diário de energia (P>0,05) sobre o peso final, ganho de peso e percentagem de gordura abdominal, havendo um aumento destes com o aumento da densidade energética. Foram constatadas pioras significativas, com efeito linear, na conversão alimentar por massa, na conversão alimentar por dúzia de ovos produzidos e conversão de energia, em função do aumento da energia consumida diariamente. Foram constatados efeitos significativos, com efeito quadrático na percentagem de casca em função do consumo diário de energia. Já para percentagem de gema e albume houve efeito linear em relação ao consumo de óleo, sendo que para o primeiro parâmetro houve aumento do mesmo com maior inclusão de óleo e, no outro, diminuição. Houve efeito significativo do consumo diário de óleo (P<0,05) e da interação consumo de energia e consumo de óleo (P<0,05) sobre Unidades Haugh. Houve efeito significativo da cor da gema em função do consumo diário de energia e óleo diários (P<0,05). / The present experiment was carried out at the experimental aviary of the Veterinary Medicine and Zootecny University - Botucatu. At the beginning of the experiment 288 semi -heavy Hisex Brown strain birds were used, in production, 30 weeks old, divided in nine treatments with four replications each, in a factorial arrangement 3X3, with three levels of metabolizable energy supplied per bird/day (280, 300 and 320 kcal) and three different oil consumptions for bird/day (0.00; 0.75 and 1.50 g). The birds had a restricted daily feed consumption of 115, 110 and 105 9 to obtain the levels of metabolizable energy and oi!. The diets were balanced so that ali of the experimental birds received 18 9 of crude protein daily, 4.2 9 of Calcium, 0.66 9 of Total Phosforus, 0.40 9 of Methionine, 0.73 9 of Methionine + Cistine and 0.83 9 of Cistine. The parameters of production (%), mass (g/bird/day), average weight (g) and specific gravity of the eggs where not humidity, fat percentage, protein and ash of the albumen and yolk didn \'t differ significantly different among the treatments. There was a significant effect of the daily consumption of energy on the final weight, weight gains and percentage of abdominal fat, which demonstrate an increase of these parameters with the increase of the energy density. Significant worsenings were verified (P < .05), with linear effect in the feed conversion for mass, in the feed conversion for dozen of produced eggs and conversion of energy, in function of the increase of the energy consumed daily. Significant effects were verified, with quadratic effect in the shell percentage in function of the daily consumption energy. However for yolk percentage and albumen there was a linear effect to oil consumption and for the first parameter there was an increase of that with larger oil inclusion and, in the other one, decreased. There was significant effect of daily consumption of oil (P < .05) and of the interaction consumption of energy and oiI consumption (P < .05) on Haugh Units. There was a significant effect of the color of the yolk in function to the daily consumption of energy and oil (P <.05).

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