ABSTRACT The objective of this study was to evaluate the effect of the presence of roosters on welfare and egg production of laying hens reared in an alternative system. Two breeding systems were established: barn 1 - laying hens reared without roosters (4500 birds); and barn 2 - laying hens reared with roosters (4500 layers and 250 roosters). In the poultry facilities, microclimate, egg production, mortality rate, and bird behavior were evaluated. Microclimate analysis showed that the birds were subjected to periods of constant heat stress, except for the morning hours. However, even under these conditions, egg production results and mortality rate were consistent with the indices recommended in the Isa Brown management guide in the barn with roosters; the indices obtained were even better and were characterized by higher egg production and lower mortality rates. In addition to productivity benefits, the presence of roosters broadened the behavioral repertoire of the birds due to the introduction of reproductive behaviors. Moreover, there was a significant decrease in the tolerance-reflex behavior, which is associated with the impossibility of displaying reproductive behaviors. This alternative egg production system proved to promote animal welfare since it provides and stimulates the display of behaviors considered important for birds.

ABSTRACT The purpose of this study was to evaluate the effect of glutamine supplementation plans on performance, carcass yield, and cut yield of broilers reared in a high-temperature environment. A fully randomized design was adopted for the experiment, comprising 900 male Hubbard broiler chicks assigned to five treatment groups (0% glutamine from one to 42 days of age; 0.5% glutamine from 1 to 7 days of age, followed by 0% from 8 to 42 days; 1.0% glutamine from 1 to 7 days of age, followed by 0.5% from 8 to 14 days and 0% from 15 to 42 days; 1.5% glutamine from 1 to 7 days of age, followed by 1.0% from 8 to 14 days, 0.5% from 15 to 21 days, and 0% from 22 to 42 days; 2.0% glutamine from 1 to 7 days of age, followed by 1.5% from 8 to 14 days, 1.0% from 15 to 21 days, and 0% from 22 to 42 days), consisting of six replicates of 30 animals each. The experiment was composed of four periods: pre-starter (1-7 days), starter (8-21 days), grower (22-33 days), and finisher (34-42 days). Glutamine supplementation plans up to 21 days do not improve the performance of broilers in the periods from 1 to 21 and from 1 to 42 days of age reared in a high-temperature environment. Carcass yields and cuts of broilers at 42 days of age are not changed by glutamine supplementation for up to 21 days.