The Effects of Intrauterine Injection with Prostaglandin F_2α, Arachidonic Acid and Phosphate Solution on the Eggshell Formation of Japanese Quail Hen

Inhibitory effects of prostaglandin F_2α, arachidonic acid and phosphate solution on the eggshell formation were investigated in Japanese quail. All injections were performed intrauterinely 8 h before the predicted oviposition. Prematurely oviposited eggs distinctly presented significantly lower values of eggshell weight (64-70%) and eggshell thickness (65-70%) than those of control (p<0.01). Spontaneously oviposited eggs, of which averaged oviposition intervals were approximately 24 h, also showed significantly lower values (p<0.01) than control in eggshell weight and thickness (71-79% in both). When indomethacin was pretreated, oviposition-inducing effect and inhibiting effect on eggshell formation were disappeared in injection with arachidonic acid, whereas not inhibiting effect on eggshell formation but oviposition-inducing effect only disappeared in injection with phosphate solution. These results indicated that prostaglandin and phosphate solution had the inhibitory effect on the eggshell formation.