Sr. Caldwell et al., Increased egg production in juvenile turkey hens after active immunizationwith vasoactive intestinal peptide, POULTRY SCI, 78(6), 1999, pp. 899-901
Juvenile turkey hens were actively immunized against vasoactive intestinal
peptide (VIP) prior to photostimulation to evaluate its effect on enhancing
egg production. VIP antibody titers were generated in the VIP immunized he
ns and a greater rate of egg production per hen was observed compared to co
ntrols. In addition, the first egg laying cycle was extended for an additio
nal 7 wk without a significant decline in egg production. Over a 27-wk peri
od, 116 settable eggs per hen were produced from the VIP immunized hens as
compared to 102 and 90 eggs for the keyhole limpet hemocyanin and saline co
ntrol groups, respectively. Based on the increased egg production and the e
xtension of the first egg laying cycle, this experiment demonstrates that V
IP immunization of turkey hens is potentially economically relevant.