Conforto térmico de bovinos leiteiros confinados em clima subtropical e mediterrâneo pela análise de parâmetros fisiológicos utilizando a teoria dos conjuntos fuzzy AMENDOLA et al. (2005b). The use of this tool allowed the establishment of thermal comfort parameters for total confined Holsteins cows.

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This experiment was carried out in a 104 m² poultry house located between the geographical coordinates 25°45'00" south latitude and 53°03'25" west longitude and an average altitude of 550 m, from September to November, 2008. The chickens were placed in 12 pens measuring 2 m² each at a stocking density of 12 chickens m-2. This study aimed at evaluating the effect of two different initial weights (chick weight on first day of experiment) and two types of litter material on broiler production parameters, litter humidity, as well as on breast and footpad lesions. A total of 240 female Cobb® chickens, derived from the same flock of breeders, was distributed in a completely randomized experimental design with a 2 (initial weight) by 2 (litter material) factorial arrangement with three replicates per treatment. Initial weights were classified as light (34.40 - 35.22 g) or heavy (39.29 - 41.30 g), whereas wood shavings and sawdust were used as litter material. Data were analyzed by ANOVA and means were compared by Tukey's test at 95% confidence level. Initial weight significantly influenced bird performance, as chickens with heavy initial weight presented higher feed intake and body weight. Type of litter did not have any effect on breast injuries and litter humidity. However, the wood shavings litter significantly influenced footpad lesions

This study aimed at identifying the factors that affect the financial performance of broiler chicken production in Southwest of Paraná state in Brazil, as well as to study the relationship of these factors with the social-economic situation of poultry farmers. Data were obtained from a questionnaire applied to broiler chicken farmers between February and March, 2011. The questionnaire included 39 questions relative to farmer's age, family size, land possession, capital invested in broiler farming, gross income per flock, training and broiler farming experience, production size, credit needs, technical service, labor, production problems, and bird weight at slaughter. Data were submitted to descriptive statistical analysis. The relationship between production data and financial performance was determined using Pearson correlation coefficient, at 95% confidence level. Approximately 64.84% of the interviewed broiler farmers in Paraná state presented medium to low financial performance. Factors such as education level, facility size, labor, gross income per flock, and average bird weight at slaughter had a positive impact on financial performance. The production problems that most affected the broiler production were environmental challenges, poor feed conversion, as well as management problems and low-quality chicks.

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ResumoRealizou-se este trabalho com o objetivo de avaliar o desempenho produtivo e o rendimento de carcaça de diferentes linhagens e sexagens de frangos de corte. Foram avaliadas 576 aves das linhagens Cobb, Ross e Hubbard, dispostas nas sexagem macho, fêmea ou misto, abatidas aos 45 dias de idade. Utilizou-se o delineamento inteiramente casualizado (DIC), num bifatorial 3 x 3 (linhagens x sexagem), com quatro repetições e 16 aves em cada tratamento. O peso vivo, ganho de peso, consumo de ração e conversão alimentar apresentaram diferenças significativas no decorrer das fases avaliadas, porém, mostraram-se semelhantes ao final do período avaliado. O desempenho dos machos apresentou superioridade em comparação com as fêmeas e os mistos. No rendimento de carcaça, não foi possível observar diferenças significativas entre as linhagens e sexagens das aves; no entanto, em alguns cortes nobres a linhagens Cobb apresentou melhores resultados. Palavras-chave: avicultura; genética; mercado consumidor; tecnologia. Abstract:We carried out this study to evaluate the productive performance and carcass yield of different strains and sexing of broilers. We evaluated 576 birds of Cobb, Ross, and Hubbard strains, arranged in male, female or mixed sexing, slaughtered at 45 days of age. We used a completely randomized design (CRD), in a 3 X 3 factorial (strain X sex), with four replicates per treatment. Body weight, weight gain, feed intake, and feed conversion showed significant differences in the course of the phases evaluated; however, they were similar at the end of the study period. Males showed superior results compared to females and mixed sexing. Carcass yield showed no significant differences among strains and sexing of birds; however, in some prime cuts, Cobb presented the best results.

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Density-dependent dynamics have considerable effects in many ecological processes and patterns that characterize natural populations. In the present study, we aim at evaluating the effect of density on the diet width and between-individual variability in nine different pike cichlid Crenicichla lepidota populations dwelling in floodplain lagoons. Our results indicated that low-density populations exhibit small diet breadth as well as small betweenindividual variability in their diet. In addition, these populations were characterized by a nested diet pattern, where the diet of specialist individuals represented a subset of the food items consumed by generalist individuals. Populations with intermediate densities had a larger populational diet breadth while the individual diet breadth remained unchanged. This pattern was due to an increase in between-individual variability in diet, which consequently decreases the diet overlap among individuals and thus lower diet nestedness. Finally, under high densities, the niche width at the population level decreased because of lower between-individual variability and higher diet overlap. Together, these results showed that niche width exhibits a non-linear function with density. At first, an increase in density increased the niche width because of greater between-individual diet variability. However, after a threshold density value, the effect was reversed, and the niche width decreased because of a higher diet overlap among individuals.