ABSTRACT This study aimed to evaluate the thermal response of three strains of hens housed in a cage-free system at the Amazon rainforest in order to evaluate how feather coverage influences thermal exchange with the environment. The experimental method was completely randomized and treatments comprised three strains of hens (Rhode Island Red (red feathers with feathers on the neck), alternative strain FCI (red feathers without feathers on the neck), and alternative strain FCIII (white feathers without feathers on the neck)), with 20 hens (replicates) analyzed per strain. Thermal images of each bird were captured in order to record the birds’ surface temperatures on five points in five targets. All data collected in this study were subjected to ANOVA and subsequently to the Tukey test at p≤0.01 and p≤0.05. The aviary’s left wall presented a lower average temperature, indicating lower heat accumulation, while the floor presented higher heat accumulation. FCIII hens (white feathers) presented higher (p<0.05) heat accumulation on the head and legs, and lower (p<0.05) heat accumulation on the neck and back in relation to other analyzed hens, indicating increased heat exchange efficiency and high concentration of this process in specific body areas. FCI and FCIII hens (without feathers on the neck) presented lower (p<0.05) heat accumulation on the neck and higher (p<0.05) heat accumulation on the head and legs, indicating that the feather coverage directly influenced heat exchange mechanisms, and an increased area without feathers provided great heat exchange zones for birds in a tropical climate.

ABSTRACT The objective of this study was to determine the ideal requirement of sodium to molted laying hens. The experimental period lasted 105 days, divided into five periods of 21 days. Hisex White laying hens 150 with 84 weeks-of-age were used. The experimental design was completely randomized in a factorial scheme (5x3) with treatments constituted by five levels of sodium (0.10, 0.15, 0.20, 0.25, and 0.30%) in the diets, and three postmolt stages (early = 21 days, medium = 63 days, and final = 105 days). Performance and egg quality results were evaluated by Tukey test at 5%. Eggshell resistance and weight gain results were evaluated by polynomial regression at 5%. Except the yolk height, all performance and egg quality variables were affected (p<0.05) by the sodium levels and the hens’ age postmolt. The level of 0.15% of sodium in diets to postmolt laying hens provided better performance and egg quality, especially in the eggshell. Higher levels of sodium negatively affected the performance and egg quality. Hens in the early stage of postmolt period presented better performance and egg quality. At long-term, the postmolt hens presented worst results.

ABSTRACT The present study aimed at evaluating the effects of a coating based on copaiba oil on the quality of eggs stored for different periods. Eggs were coated with copaiba oil solutions (4, 8, 12, 16, or 20% copaiba oil) or not (control) and stored for 1, 7, 14, 21, 28 or 35 days at room temperature. The following parameters were evaluated: egg weight loss, egg components (albumen, yolk, and eggshell) relative weights, egg specific gravity, Haugh units, eggshell quality, and sensorial attributes. Eggs stored for 35 days presented the highest weight losses. Coating (20% copaíba oil solution) reduced egg weight loss up to 41.02%. Coated eggs presented better internal quality (yolk and albumen heights, specific gravity, and eggshell strength). Sensorial attributes were negatively affected by storage time (aroma and flavor), and copaiba oil solution (aroma, appearance, and flavor), with the natural odor of copaiba described by the tasters. Egg internal, external, and sensorial quality worsened with storage time. Solutions containing 16 and 20% copaiba oil can be used as a biofilm to coat eggs, preserving its internal and external quality, and may affect their sensory characteristics, and therefore, may be a viable alternative for maintaining the internal quality of eggs stored at room temperature for long periods.

ABSTRACT The present study aimed to evaluate increasing levels of fish waste oil in laying hens diets on performance, egg quality, and sensory features of the eggs. 192 Hisex White laying hens with 29 weeks of age were used, with water and food ad libitum. The experimental design was completely randomized consisting of eight treatments corresponding to the inclusion levels of fish waste oil (0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 and 3.5%) in the diets, with four replicates of six birds each. Data collected were subjected to polynomial regression at 5% of significance. Differences (p<0.05) were observed in feed intake and egg mass. Feed intake increased until 2.50% of fish waste oil in the diets. Differences were not observed (p>0.05) in all variables analyzed. Differences were observed (p<0.05) in flavor. Eggs from birds fed diets up to 2.00% present better acceptance by the tasters. Above this level, there was a considerable drop in acceptance. From these results, the present study indicates that the use of fish waste oilin laying hens diets did not affect the egg quality. However, its high inclusion negatively affected the feed intake, egg mass, and egg flavor.

ABSTRACT Three experiments were conducted to estimate the digestible lysine requirements of slow-growing broilers on their performance, carcass traits, and breast meat quality. Different broilers were evaluated in each experiment. In Experiment 1, broilers were evaluated from 29-49 days of age (grower phase I), in Experiment 2, from 50 to 69 days old (grower phase II), and in Experiment 3, from 70-84 days old (finisher phase). A completely randomized design with five treatments of four replicates each was applied in all experiments. The following dietary digestible lysine values were investigated: 0.871, 1.011, 1.151, 1.291 and 1.431% in Experiment 1; 0.803, 0.943, 1.083, 1.223 and 1.363% in Experiment 2; and 0.766, 0.906, 1.046, 1.186 and 1.326% in Experiment 3. In all three experiments, digestible lysine values quadratically affected feed intake, weight gain, and feed conversion ratio. Lysine intake linearly increased with increasing digestive lysine values, whereas lysine utilization efficiency linearly decreased. Lysine requirements for maximum feed intake (1.298, 1.109, 1.150%), weight gain (1.183, 1.199, 1.162%), and feed conversion ratio (1.203, 1.162, 1.126%) were estimated in Experiments 1, 2 and 3. Digestible lysine requirement for carcass yield were estimated as 1.162, 1.068 and 1.107% in experiments 1, 2 and 3, respectively. Lysine influenced the physical-chemical parameters broiler breast meat. Digestible lysine levels of 1.203, 1.162 and 1.126% are recommended in the diets of Redbro Plume broilers during the phases 29-49, 50-69 and 70-84 days of age to optimize feed conversion ratio.