The objective of the present study was to evaluate mortality and performance, darkling beetle population (Alphitobius diaperinus), light intensity, electrical energy consumption and economic efficiency of broilers reared under two lighting programs (nearly continuous or intermittent) and two curtain colors (yellow or blue). The experiment was conducted between June, 2004 and May, 2005. Six flocks were sequentially housed in four 12 × 10 m broiler houses divided into 4 pens with 200 birds each. Litter was reused six times or until flock 6. Body weight and feed conversion were determined on days 21, 35, and 42 of each flock. Mortality was recorded daily. Electrical energy consumption was recorded at the end of the grow-out of each flock (every 42 days). A completely randomized design in a 6 × 2 × 2 factorial arrangement (flocks, lighting programs, curtains) with four replicates per treatment was applied. Broilers reared in houses with yellow curtains and under nearly continuous lighting programs presented the best feed conversion ratio and the highest body weight. Nearly continuous lighting programs resulted in 1.48 times more sudden deaths and 1.34 times higher general mortality when compared with intermittent lighting programs. Electrical energy consumption was 2.12 times higher in nearly continuous lighting programs in relation to intermittent lighting programs. The presence of darkling beetles was higher in broiler houses with blue curtains and intermittent lighting program. The economic analysis showed the feasibility of using a mixed system, with intermittent light program in winter and spring and nearly continuous lighting program in the summer and autumn, both in broiler houses with yellow curtains.

The objective of the present study was to evaluate carcass and parts' yield, abdominal fat deposition and breast and foot pad blisters of broilers reared under two lighting programs (nearly continuous or intermittent) in broilers houses with yellow and blue curtains. The experiment was conducted between June, 2004 and May, 2005. Six flocks were sequentially housed in four 12 × 10 m broiler houses divided into 4 pens with 200 birds each. The litter was reused six times or until flock 6. A completely randomized design in a 6 × 2 × 2 factorial arrangement (flocks, lighting programs, curtains) with four replicates per treatment was applied. A total of 288 birds were evaluated for carcass yield. Curtain color did not affect carcass or parts' yield. The effect of lighting program and curtain color on carcass yield may depend on other factors related to flock. Intermittent lighting program promoted the highest drumstick and thigh yields. Lighting programs and curtain colors did not affect abdominal fat deposition or the presence of breast and foot pad blisters.

The objective of this study was to evaluate the thermal comfort of broilers reared under two lighting programs (almost continuous and intermittent) in broiler houses with yellow or blue lateral curtains. The experiment was carried out from June 24, 2004 until May 12, 2005. Six consecutive flocks were housed in four 12 × 10 m broilers houses internally divided into four pens of 200 birds each. Six flocks were raised on the same litter. The registration of data was accomplished at 3-hour intervals, for 24 hours twice a week. In the center of each pen and outside the house, dry and wet bulb temperatures, black globe temperature, and air velocity were collected. Based on the data collected at each time, air temperature (AT) (ºC), black globe humidity temperature index (BGHTI), radiant thermal load (RTL) (W/m²), and relative air humidity (RH) were determined. Harmonic analysis was used to estimate m, R, and f parameters. In general, the best results in terms of thermal comfort for the birds were found when near-continuous lighting program and yellow curtain were used.

Foram avaliados a qualidade da casca de arroz e palhada de soja como substrato de cama e o efeito da reutilização da cama por quatro lotes de frangos de corte sobre a população de cascudinhos e parasitos intestinais e como adubo orgânico. O experimento foi realizado em quatro aviários de 12 m × 10 m para frangos de corte, divididos internamente em quatro boxes/aviário, com 200 aves/boxe por quatro lotes consecutivos, cada lote com a duração de 42 dias e com intervalo de vazio sanitário de 15 dias, entre lotes. Os tratamentos avaliados foram dois sistemas de ventilação (fixo e oscilante) e dois tipos de material de cama (palhada de soja e casca de arroz). A população de cascudinhos foi acompanhada coletando-se os insetos em armadilhas, três por boxe, e a contaminação da cama por endoparasitos por contagens de ovos/oocistos por grama de cama. Os níveis de matéria seca, nitrogênio total, fósforo total, potássio, cobre, zinco, manganês, ferro, carbono orgânico e pH foram avaliados por análises físico-químicas de amostras das camas em cada lote. As camas de frango utilizadas por três lotes, em média, se enquadram às exigências mínimas legais para serem comercializadas como fertilizante orgânico simples, independentemente do tipo de material utilizado como substrato. A palhada de soja apresentou maior contagem de cascudinhos, tanto com ventilação fixa quanto com ventilação oscilante. A probabilidade de a cama de casca de arroz apresentar contaminação por oocistos de Eimeria spp. é 18,78 vezes maior que a da palhada de soja quando ambas são submetidas à ventilação oscilante e 1,32 vez maior quando sob ventilação fixa. A temperatura da cama não interfere significativamente nos níveis de contaminação por oocistos.

It was evaluated the quality of rice husks or soybean straw as litter substrate and the effect of litter reuse for four consecutive flocks of broiler chickens on populations of darkling beetle and intestinal parasite and as organic fertilizer. The experiment was carried out in four 12 m × 10 m poultry houses, internally divided in 4 boxes/poultry house with 200 birds/pen for four consecutive flocks, each flock with a duration of 42 days and with a 15-day downtime between flocks. The evaluated treatments were two ventilation systems (stationary or oscillating fans) and two litter materials (soybean straw or rice husks). Darkling beetle population was followed by collecting the insects in traps, three traps per box, and endoparasite litter contamination was determined by eggs/oocyst counts per gram of litter. Levels of dry matter, total nitrogen, total phosphorus, potassium, copper, zinc, manganese, iron, organic carbon and pH were evaluated by physical/chemical analyses of samples of the litters in each flock. Overall, litters of broilers used by three flocks meet the minimal legal requirements to be marketed as simple organic fertilizer, regardless to the material used as substrate. Soybean straw presented higher darkling beetle counts in stationary ventilation system as well as in oscillating ventilation system. The probability of rice husks litter present contamination by Eimeria spp oocysts is 18.78 times higher in rice husks than in soybean straw litter when both are submitted to oscillating ventilation, and 1.32 higher when stationary ventilation is used. Litter temperature does not influence significantly levels of contamination by oocysts.

Este trabalho foi conduzido com o objetivo de avaliar as condições térmicas ambientais em aviários com dois sistemas de ventilação e dois materiais de cama. O experimento foi realizado em quatro aviários de 12 m × 10 m para frangos de corte, divididos internamente em 4 boxes/aviário, com 200 aves/boxe por quatro lotes consecutivos, cada um com duração de 42 dias e com intervalo de vazio sanitário de 15 dias entre lotes. Os tratamentos testados foram dois sistemas de ventilação (fixo e oscilante) e dois tipos de material de cama (palhada de soja e casca de arroz). Foram coletadas no centro de cada boxe e no ambiente externo a temperatura de bulbo seco e úmido, a temperatura de globo negro e a velocidade do ar. Esses dados foram coletados em intervalos de três horas, de 8 às 18 horas, na quarta, quinta e sexta semanas de vida das aves. Com base nos dados coletados em cada horário, foram determinados o índice de temperatura de globo e umidade (WBGT) e a carga térmica radiante (RHL). Também foram feitas leituras da temperatura da cama por meio de termômetro infravermelho. Na análise dos dados de ambiente térmico interno, foram avaliados os efeitos de lote, ventilação, semana, hora e as interações dos fatores sobre as variáveis avaliadas, utilizando-se a teoria de modelos mistos para medidas repetidas. A ventilação proporcionada por ventiladores fixos e oscilantes comportou-se igualmente e não teve efeito sobre as variáveis estudadas. No entanto, as duas formas de ventilação são suficientes para amenizar as condições térmicas internas do aviário em relação ao ambiente externo. A umidade relativa do ar é maior quando se utiliza a casca de arroz como material para cama.

The objective of this study was to evaluate environmental thermal conditions in broiler houses with two different ventilation systems and two different litter materials. The experiment was carried out in four 12 m × 10 m broiler houses, internally divided in 4 boxes/poultry house, with 200 birds/pen for four consecutive flocks, each one with a duration of 42 days with 15 days of downtime between flocks. Treatments tested were two ventilation systems (stationary or oscillating fans), and two types of litter materials (soybean straw or rice husks). It was collected in the center of each pen and in the external enviroment, dry and wet bulb temperatures, black globe temperature, and air velocity. These data were collected at 3-hour intervals from 8:00 a.m. to 6:00 p.m. at the fourth, fifth and sixth week age of the bird. Based on the data collected at each time, wet and globe temperature index (WBGT) and radiant heat load (RHL) were determined. Litter temperature reaings were also performed by using an infrared thermometer. Effects of flock, ventilation, week, hour and the interactions among factors on the studied variables were evaluated in the analysis of the internal thermal environment by using the theory of mixed models for repeated measures. Ventilation provided by stationary and oscilating fans had equal behavior and it did not affect the studied variable. However, both ventilation systems are sufficient to soften internal thermal conditions in the broiler house in relation to the external environment. Relative humidity of the air is higher when rice husks is used as litter material.