Comparison of forced molt and natural molt in white leghorns caged in two population densities

Abstract

Foreign literature reports an economic advantage in the recycling of laying hens for a second year as compared with complete replacement with a new flock. Two methods of recycling laying hens were compared in this study; natural molt and forced molt using the method described by Carson in 1966. There was no difference between the two methods with respect to egg production or to quality of eggs under the climatic conditions of Rio de Janeiro. Observed differences in egg production and egg quality were related to density in the cages and to season of the year but not to the experimental methods themselves. The physiological stress caused by forced molt was not sufficient to cause a complete inversion of the hormonal and metabolic activities of the birds. These results lead the authors to suggest new research on methods of forcing molt that would be effective under tropical conditions.