Shell gland responsiveness to prostaglandins F2α and E1 and to arginine vasotocin during the laying cycle of the domestic hen (Gallus domesticus)

Contractile responses of isolated shell gland (SG) strips from laying hens displayed no significant differences 6 hrs before oviposition, at oviposition, and 6 hrs after oviposition when stimulated with arginine vasotocin (AVT), prostaglandin E₁ (PGE₁), or prostaglandin F_2α (PGF_2α). Dose-response curves show that the sensitivity of the SG to these agents, in vitro, is: AVT > PGF₂ > PGE₁. PGF_2α, however, produces the largest contractile response, while PGE₁ appears to be a poor agonist of contractile activity in vitro. These results are discussed in relation to the known hormonal patterns during the ovulatory cycle of the hen and the physiological roles attributed to these oxytocics in the control of oviposition.