A transplantation technique for transferring adult worms of Ascaridia galli to parasite-naive recipient chickens is described. The aim was to find a less traumatic transplantation technique than surgical transplantation, as well as a technique that would avoid worm injuries due to worm passage through the chicken proventriculus and gizzard. Thirty experimental growers were divided into 3 groups. Group 1 animals were fasted for 24 hr before transplantation, and group 2 received an antiperistaltic treatment before and after the transplantation. Animals in group 3 received no special treatment. All animals were fasted for 2 hr before anesthesia and pretreated with atropine. The chickens were anesthetized, and each received 2 male and 2 female worms of Ascarid. galli by cloacal intubation. The tube was inserted and the worms flushed out of the tube as anteriorly as possible in the rectum. Fecal samples were examined during the experimental period to monitor the eventual parasite egg excretion. Two weeks after transplantation the birds were slaughtered and the intestines examined for adult Ascarid. galli. Infection was established in 20% of the animals belonging to groups 1 and 2, and in 60% of the animals in group 3. This transplantation technique enables direct establishment of infections of adult Ascarid. galli in chickens, although the exact worm sex composition of the infection is still unpredictable because of expulsion of worms after transplantation. The method is less traumatic to the experimental animal than are surgical techniques.