Epithelial ovarian cancer is the most lethal gynecologic malignancy, with a 5-year survival rate of less than 40%. This is due in part to a lack of early detection markers and lack of specific symptoms during early disease. The laying hen is the only accessible animal model which develops epithelial ovarian cancer spontaneously, with features closely resembling the human disease. It has been estimated that approximately 30% of all cancers can be prevented with diet, exercise, and maintenance of an optimal weight, and the chronic low-grade inflammation that accompanies obesity is implicated as a causal factor in the development of cancer. Flaxseed, a rich plant source of anti-inflammatory omega-3 fatty acids and lignans which act as phytoestrogens and antioxidants, exhibits chemosuppressive effects against the development and progression of ovarian cancer. We have shown that a diet of 10% flaxseed reduces the incidence and severity of ovarian cancer when fed to laying hens over 4 years, due in part to the ability of flaxseed to suppress the production of proinflammatory PGE2 in the ovary by decreasing expression of COX enzymes. To investigate other potential specific mechanisms by which flaxseed acts to suppress ovarian cancer, we examined expression and activity of pathways known to be involved in the etiology and progression of human epithelial ovarian cancer in ovarian cancer in the laying hen, and determined whether flaxseed affected these pathways during cancer development. We investigated the effect of flaxseed and its individual components upon oxidative stress in the normal ovary and in ovarian cancer by analyzing expression of target genes of the NRF2 transcription factor. The NRF2 pathway is a "master switch" that regulates expression of ROS-responsive detoxification genes. Results revealed that expression of four genes was significantly downregulated in then ovaries of hens on the defatted flaxmeal (DFM) and whole flaxseed (WF) diets compared to hens on diets that are high in pro-inflammatory omega-6 fatty acids, suggesting that flaxseed decreases oxidative stress in the ovary. Conversely, one target gene was upregulated in ovarian cancer compared to normal ovaries, and this observation was not affected by flaxseed. Additionally, nuclear accumulation Nrf2 protein was not observed in tumor cells, suggesting that flaxseed does not exert chemosuppressive effects by modulating NRF2 signaling in ovarian cancer. To further investigate pathways potentially regulated by flaxseed, we performed a microarray with 44k features and found that a set of genes involved in branching morphogenesis was upregulated in ovarian cancer and significantly decreased by flaxseed, including E-cadherin and miR-200, suggesting that flaxseed impedes the activity of an aberrantly activated developmental program that controls gland formation during ovarian cancer progression. Lack of nuclear accumulation of ZEB1 protein in tumor cells suggests that this decrease in expression is likely not due to EMT. Finally, due to its known roles in controlling developmental programs such as EMT as well as regulating cell growth and proliferation, we performed a set of experiments to examine activity of the TGF-beta pathway. PCR array analysis revealed that SMAD target genes, ligands, receptors, and co-regulatory proteins were upregulated in ovarian tumors from hens on both diet groups, suggesting TGF-beta signaling is enhanced in ovarian cancer. However, expression of SMAD6 and SMAD7 was upregulated in tumors from hens on the flaxseed diet but not control diet, with SMAD7 protein being expressed in both epithelial tumor cells and intratumoral stromal cells. Additionally, immunohistochemical staining for pSMAD2/3 was decreased in epithelial tumor cells and absent from intratumoral stromal cells in tumors from hens on the flaxseed diet compared to tumors from hens on the control diet, and these data together suggest that flaxseed may inhibit pro-oncogenic TGF-beta signaling in ovarian cancer. Finally, flaxseed prevents the downregulation of expression of p15 and the upregulation of CCNA and CCNE in ovarian tumors, suggesting that flaxseed may slow cell cycle progression. Data from these studies provides preliminary evidence that flaxseed exerts pleiotropic effects upon gene expression to negatively regulate pathways driving the progression of ovarian cancer, including aberrant TGF-beta signaling and glandular development. These studies provide groundwork for in vitro studies to test the specific effects of flaxseed upon proteins involved in TGF-beta signaling and upon the expansion of tumor epithelia.

Ovarian cancer is a deadly gynecological disease that ranks fifth in all cancer-related deaths inwomen. The disease is often detected at an advanced stage and lack of sensitive predictive biomarkerscontribute to its poor prognosis, which is also responsible for the current five-year survival rate of only47%. Our laboratory has previously shown that a whole flaxseed supplemented diet decreases the onsetand severity of ovarian cancer in the laying hen, the only known animal model of spontaneous ovariancancer. Flaxseed is rich in omega-3 fatty acids (OM3FA), mostly α-Linoleic acid (ALA), which getsconverted to Docosahexaenoic acid (DHA) by the action of delta-6 desaturase enzyme. We have also shownthat the flaxseed diet in hens induces CYP1A1 expression in the liver while suppressing both CYP1B1 andCYP3A4 expressions. The upregulation of CYP1A1 parallels the increase in 2-hydroxyestradiol and the 2-methoxyestradiol (2MeOE2) level in the serum of the chickens. Flaxseed diet induces apoptosis to ovariantumors and not in the normal ovarian tissues. The current work explores the pro-apoptotic actions of oneof the biologically derived compounds of flaxseed diet, 2MeOE2, and describes one of its novel molecularactions. Our results indicate that 2MeOE2 -mediated pro-apoptotic actions are partly dependent on thecatalytic activation of protein kinase C delta (PKCd), which is responsible for key apoptotic histonemodifications and p38 MAPK (MAPK14) phosphorylation. Phosphorylated MAPK14, in turn, results inmore caspase-3 cleavage which activates more PKCd, therefore amplifying the apoptotic signal.The other part of this work explains one of the key anti-cancer actions of a flaxseed diet. Flaxseedreduces the number of endothelial cells and increases pericytes to endothelial cell ratio in ovarian tumorscompared to control diet-fed birds, indicating a reduction in tumor angiogenesis and an improvement inblood vessel maturation. Flaxseed decreases a-smooth muscle actin expression in ovarian tumors, whichmarks a decrease in cancer-associated fibroblasts (CAFs) in the tumor stroma. Flaxseed also reduces fibrosisin ovarian tumors. Flax -mediated reduction of ovarian fibrosis parallels an increased infiltration ofimmune cells in the preneoplastic ovaries and ovarian tumors. Therefore, this work describes how the flaxdiet differentially targets the ovarian tumor cells and the tumor stroma in preventing the incidence andseverity of ovarian cancer. Dietary supplementation with flaxseed can, therefore, be a healthy lifestylechoice as well as a potential adjuvant therapy for immunotherapy-based treatment modalities.

Light-emitting diode (LED) is an improved light delivery technology that provides better energy efficiency, longer lifespan, and the ability to select a specific wavelength of light. We evaluated the effect of blue and red-LED on performance, behavior, egg quality, hormonal concentration, and prevalence of Avian pathogenic E. coli (APEC) like E. coli in pullets and laying hens raised in cageree housing system. Results showed that birds raised in blue-LED during the pullet phase had higher body weight and earlier onset of early lay. Red-LED increased the yolk percentage, illustrating that red-LED can stimulate reproduction. Red-LED also decreased the relative spleen percentage, which is an indication of decreased immunity. Overall egg production was not affected by the light treatment. Irrespective of the light treatment, a higher prevalence of APEC like E. coli was found in colonies isolated from the trachea suggesting a possible route of transmission in cageree housing system.

Genetic selection for improved performance has necessitated the frequent update of amino acid requirements to support this improvement. The first objective of this dissertation was to investigate the tryptophan requirement of laying hens in peak production and the lysine and sulfur amino acid requirements of broiler chicks under a phase feeding scenario using different models. Digestible tryptophan requirements were estimated to be 137 for egg production, 133 for egg mass, and 133 for feed efficiency using the linear broken-line model. The lysine and sulfur amino acid requirement were estimated by conducting 3 experiments within the starter phase from 2 to 5, 5 to 8, and 8 to 11 days of age. The linear broken line estimate for digestible lysine was 1.22, 1.17 and 1.16% for BWG and 1.31, 1.21, and 1.14% for FCR in experiments 1, 2, and 3, respectively. The linear broken line estimate for sulfur amino acids was 0.82, 0.81 and 0.94% for BWG and 0.82, 0.80, and 0.90 for FCR in experiments 4, 5, and 6, respectively. The lysine requirements decreased from 2 to 5 to 8 to 11 days, however the sulfur amino acid requirements increased during that same period. This could be due to other roles that sulfur amino acids play in the body other than growth. The second objective of this dissertation was to investigate the effects of a direct fed microbial (DFM) on broilers exposed to a cyclic heat stress in 2 consecutive experiments. In this experiment, the heat stress treatment reduced body weight gain and lean tissue accretion from 0 to 35 d in both experiments. In Experiment 2, when the litter was reused BWG was increased by 36 g/bird with supplementation of DFM. Ileal digestibility at 28 d (2 hr post HS) was improved with DFM supplementation in both experiments. Serum FITC-d increased with HS at both 28 and 35 d. Serum FITC-d was generally decreased with DFM at 28 d but the response was inconsistent at 35 d. Overall, the results suggest that HS reduced broiler performance and DFM treatment improved intestinal permeability and nutrient digestibility responses to HS in both experiments but did not improve performance until built up litter was used in Experiment 2. The last objective of this dissertation was to investigate the effects of sulfur amino acids (SAA) on broilers exposed to a cyclic heat stress. As expected, HS reduced BWG and worsened FCR. The supplementation of SAA had no effect on live performance. At 28 d of age, supplementation of SAA to birds exposed to HS resulted in reduced intestinal permeability. The interaction was lost at 31 d, but HS still increased intestinal permeability (P ≤ 0.05). Potential oxidative damage was reduced by increased SAA supplementation as indicated by an increase in the reduced glutathione to oxidized glutathione ratio. These data suggest that intestinal permeability is compromised acutely to at least three days of heat exposure before the bird can adjust, but oxidative damage is more chronic building over the entire 7 d HS period. SAA might have some protective effect on both intestinal permeability and oxidative stress responses to HS. / Doctor of Philosophy / To provide low-cost meat and eggs to consumers, the poultry industry must focus on improving efficiency as well as reduce the impact of stressors within the environment. This is achieved mostly by genetic selection which has resulted in significant improvements in both egg production in laying hens and body weight in broiler chickens. To support this improvement in growth rate birds would require a higher amino acid dense diet to support the increased protein output. One objective of this dissertation was to update the requirement of three key amino acids (tryptophan, lysine, and sulfur amino acids) in both laying hens and broilers for better formulation of diets. These amino acids that were investigated are essential in poultry diets and cannot be produced by the birds. The results from the tryptophan experiment indicated that laying hens need 137 mg of tryptophan per day to maintain maximum egg production. Results from the lysine and sulfur amino acid requirement experiment in broiler chickens indicated that broilers need 1.31% lysine and 0.90% sulfur amino acids to support maximal growth, but these requirements change over time and would need to be adjusted based on the broiler's age. Heat stress in the poultry industry is a major challenge which can affect the growth rate as well as the welfare of broiler chickens. The second objective of this dissertation was to investigate different strategies to ameliorate the effects of heat stress. Supplementing direct fed microbials or probiotics in broiler diets has been proposed as one of those strategies. An experiment was conducted to investigate the effect of the supplementation of a DFM on broiler chickens exposed to heat stress. The results indicated that the DFM was able to ameliorate the negative impacts of the heat stress on nutrient digestibility and intestinal permeability but did not improve the growth of the chickens. Another experiment was conducted to evaluate another strategy to ameliorate the effects of heat stress on broiler chickens which was the supplementation of sulfur amino acids. The sulfur amino acids are not only used for protein synthesis but have other physiological roles in the body that are important specifically during heat stress. Results from this experiment indicated that sulfur amino acids were able to ameliorate the negative effect of heat stress on intestinal permeability and oxidative stress but did not improve the performance of chickens subjected to the heat stress.

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.

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.

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 / High environmental temperatures can cause laying hens to become heat stressed, including reduced egg production, egg quality, and body weight, and in some cases increased mortality. Two mechanisms to reduce heat production and increase heat dissipation are reduced feed intake and increased respiration rate during heat stress. The reduced feed intake can result in insufficient nutrients to maintain egg production and increased respiration rate can change the blood chemistry, reducing ionic calcium and ultimately causing thinner eggshells. The most efficient way to reduce the negative effects of heat stress is by avoidance through controlling the environmental temperature, however, above certain temperatures cooling methods fail. If heat stress conditions are reached, it is important to understand the genetic ability of the hen to minimize the negative consequences of elevated temperature. Therefore, the effects of a four-week heat stress were determined with a focus on hen performance, egg quality, and blood chemistry parameters in laying hens. Some parameters such as blood pH and ionized calcium, shell weight, and body temperature were negatively affected within four to six hours while others, such as shell thickness, Haugh unit, and egg production took longer to be affected. By the end of the experiment blood pH returned to pre-heat stress levels but feed intake was significantly reduced over the 4 wk HS period. This could indicate that the laying hens began to acclimate to the high environmental temperatures but were not able to completely overcome the negative effects.

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.

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.

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.