R. Bras. Zootec.. 01/Mar/2017;46(3):175-84.
Presence of roosters in an alternative egg production system aiming at animal welfare
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.