 In the host's rumen, the L3 larvae shed their protective sheath and pass into the abomasum, where they penetrate the gastric glands.After exsheathment and penetration into the gastric glands the L3 moult into L4 and subsequently to L5 larvae.The young adult worms then emerge from the gastric glands and continue their maturation on the mucosal surface of the abomasum.