Changes in endocrinological parameters and production performances in Turkey hens (Meleagris gallopavo) submitted to different broody management programs.
Occurrence of broodiness, egg production, feed consumption index and changes in the LH and prolactin levels were compared for turkey hens raised under 3 broody management programs. All hens (n=60 per group) were regularly ejected from the nest (basic treatment). Moreover, one group of hens was also rotated weekly (partial treatment), while in the third group (full treatment) hens showing broody symptoms were also identified daily and isolated for 24 hours. The percentage of hens which were identified as broody at least once was similar under the 3 programs (30%), although the use of the full and partial programs were more effective in inducing the disruption and/or preventing further expression of broody behavior. Plasma LH concentrations decreased progressively throughout the reproductive cycle under the 3 treatments. Maximum plasma concentrations of prolactin were measured between the 5th and the 10th weeks of production; higher concentrations of prolactin were maintained for a longer period under the full treatment, while a lower amplitude rise in plasma prolactin concentrations was observed in the hens submitted to the partial treatment. The egg production and feed consumption indices were lower and higher, respectively, under the full treatment than the basic treatment and partial treatments. We conclude that management programs need to be carefully evaluated under commercial conditions not only with respect to broodiness expression but also to egg production.
Guémené
D
D
I.N.R.A., Station de Recherches Avicoles, Nouzilly, 37380 Monnaie, France.
Williams
J B
JB