ABSTRACT Rearing environmental conditions are important for turkey production, because this bird is particularly sensitive to heat stress. This study aimed at measuring the wattle temperature response of turkeys of three different ages (61, 96, and 131 days old) exposed to different combinations of dry bulb temperature, relative humidity, and wind speed ranges, as an indication of their physiological responses. The experiment was conducted with 42 male birds housed in a controlled environment chamber and exposed to different combinations of two air speed (WS) ranges (WS1 = 0.3-0.6 ms-1, considered low, and WS2 = 1.2-1.6 ms-1, considered high), dry bulb temperature (DBT) between 22 and 34 °C, and relative humidity (RH) between 40 to 90 %. The statistical analysis showed that WS, DBT, and RH significantly influenced wattle temperature of 61-d-old turkeys, while only WS and DBT influenced this response when turkeys were 96 days old. Furthermore, DBT was highly correlated with both low and high WS. In 131-day-old turkeys, WT response was virtually the same at both wind speed ranges when high DBT was applied. Turkey wattle temperature was influenced by wind speed, and was dependent on both environmental dry bulb temperature and relative humidity, as well as bird age.

This study aimed at identifying the factors that affect the economic efficiency of broiler breeder production using the analysis of stochastic profit frontier function. Data were collected in 48 broiler breeder farms contracted by a commercial company located in southwestern Paraná, Brazil. The collected data refer to the last batch of fertile eggs that was delivered to the company, between January, 2008, and July, 2009. The following parameters were evaluated: production of hatching eggs per hen (number of eggs/hen), hatchability (hatch %), feed intake per hatching egg (g feed/ egg), production scale (number of birds/batch), farmer's experience in production activities, and labor type. Factors, such as area of occupied land, electricity costs, and invested capital were also evaluated. Results showed that the cost of electricity, as well as area of occupied land, production scale, and feed intake per hatching egg significantly affect the economic efficiency of the broiler breeder farms in Southwestern Paraná, Brazil.

There has been a great evolution and improvement in the nutrition of poultry and lysine has been used the reference amino acid to increase animal protein deposition. Therefore, a meta-analysis was performed with the objective of studying the effect of different dietary lysine levels on the performance and carcass yield of broiler chickens. In total, 21 studies published in Brazil since 1999 were included. Bird performance considered daily weight gain (178 observations) and feed conversion ratio (188 observations) results. Carcass quality was evaluated relative to carcass yield (24 observations), abdominal fat (24 observations) and breast meat yield (30 observations). Data were checked for normality and were submitted to analysis of variance. Weight gain and carcass yield increased with the addition of 1.05% of lysine to the diet, whereas feed conversion ratio and abdominal fat were reduced as dietary lysine concentration increased. The results, therefore, indicate that lysine is essential in bird nutrition and significantly affects bird performance and carcass yield.

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.

This study aimed at evaluating the live performance of turkeys during the initial stage of production (1-26 days of age) and to map the environmental variables inside turkey houses, such as temperature, relative humidity, CO2 concentration, at two distinct minimum ventilation systems. House 1 (H1) was equipped with a negative-pressure ventilation system and House 2 (H2) was equipped with a positive-pressure ventilation system. This study was performed in commercial poultry houses, located in Francisco Beltrão, Paraná, Brazil, in June, 2008. A number of 14,000 turkeys toms at the same age, provided by the same local hatchery and were housed at a stocking density of 23 birds m-2. Three 13 m² boxes with 300 turkeys each were placed inside the poultry houses. All treatments were assigned for the birds inside each of the three boxes. The poultry barns were virtually divided in eight equally distributed in areas where the environmental variables were recorded. The performance parameters measured were weight gain, feed conversion and mortality rate, recorded weekly. Analysis of variance and F-tests were performed to compare results within different environmental conditions, using MINITAB 14 statistical software. The ventilation systems did not significantly influence CO2 concentrations (p = 0.489), whereas temperature (p = 0.016) and relative humidity (p = 0.0001) and feed conversion (p = 0.001) were significantly affected by ventilation system. Temperature and relative humidity in H2 (positive pressure ventilation system) was found to be less aversive than those in H1 (negative pressure system). Also, bids in H2 presented lower feed conversions than those in H1.

Health status, feed conversion ratio, and mortality are long known broiler chicken production indicators. However, further parameters are required by today's demanding meat markets, as these indicators are not sufficiently accurate to determine flock overall welfare. Morphological asymmetry has been pointed as an alternative welfare indicator as it reflects the ability of the bird to cope with the challenges that rearing conditions may impose. This study aimed at evaluating the possibility of using morphological asymmetry as a welfare indicator. Broilers from 28 to 42 days of age were used in the trial. Birds were randomly selected in a commercial poultry farm and transported to the laboratory. They walked over the force measurement platform in order to determined their feet force as a percentage of body weight. The following body parts of the live birds were measured by two different operators using a digital caliper: tarsometatarsus length, outertoe length, midtoe length, and backtoe length. In the corresponding carcasses, the following traits were measured: wattle width, eye length, and first secondary feather length. Data were submitted to statistical analyses and no correlation was found between specific feet trait measurements and walking ability. Considering the time budget involved in measuring morphological asymmetry, this procedure did not appear to be a practically feasible welfare indicator.