ABSTRACT The present study aimed to determine the ideal sodium levels for muscovy ducks in housing. Two hundred and forty muscovy ducks of creole lineage were used, distributed in boxes with water and food ad libitum. The experimental design was completely randomized, where treatments were constituted by six nutritional plans (initial, growth and termination) with different sodium levels, and four replicates of 10 muscovy ducks each. The birds had weekly performance evaluations, and after 90 days, eight birds (four males and four females) in each treatment were slaughtered for evaluation of carcass traits. Data collected were subjected to Tukey test at 5% of significance. Differences were observed (p<0.05) in performance (feed intake and feed conversion), where average levels of sodium presented better results. In carcass yields, average levels presented a positive influence (p<0.05) on muscovy duck growth. Male muscovy ducks presented better feed efficiency than females in the same period. The present study indicates that nutritional plan 3 (initial = 0.25%; growth = 0.30% and termination = 0.35%) showed better nutritional requirements of sodium for muscovy ducks in housing, obtaining better performance and carcass development.

ABSTRACT The present study aimed to determine the ideal requirement of digestible methionine + cystine to molted laying hens. The experimental period lasted 105 days, divided into five periods of 21 days. 144 Hisex White laying hens with 84 weeks-of-age were used. The experimental design was completely randomized with treatments constituted for six levels of digestible methionine + cystine (0.45, 0.50, 0.55, 0.60, 0.65, and 0.70%) in the diets, with four replicates of six birds each. Data collected were evaluated by polynomial regression at 5%. There was a significant effect (p<0.05) of digestible methionine + cystine on feed intake, energy intake, protein intake, egg production, and egg mass. Internal egg quality presented positive linear effect (p<0.05) on albumen height and yolk color. External egg quality was affected (p<0.05) in eggshell %, eggshell thickness and eggshell resistance, where the level of 0.60% of digestible methionine + cystine in the diets provided eggshells with better quality (higher percentage, thicker and breaking resistance). Differences (p<0.05) were also observed in glucose and triglycerides concentration, with 0.60% of digestible methionine + cystine in the diets presenting better equilibrium. Results of the present study suggested that higher levels of digestible methionine + cystine improved the performance and internal egg quality of molted laying hens. The level of 0.60% of digestible methionine + cystine provided better eggshell and equilibrium on blood biochemistry.

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.