Effects of Temperature on the Development of the Eggs of Ascaridia galli

Abstract

The intestinal roundworm, Ascaridia galli (Schrank, 1788), continues to present an economic problem to broiler growers in southeastern United States in spite of the ever decreasing growing period required to produce a 3-pound broiler. In recent studies (Reid, 1958) samples of 10 birds from each of 100 farm flocks showed 59 percent of the flocks and 27.5 percent of the birds carried A. galli at marketing time when birds averaged about 9 weeks of age. Large expenditures for worm treatment have proved disappointing in the amount of control thus achieved. Earlier studies (Ackert, 1931) suggested that the life cycle of A. galli required up to 50 days, but many birds are now marketed between 56 and 70 days, thus making it difficult for a life cycle of that duration to be completed. A restudy of the life history of the parasite thus seemed desirable to answer the riddle of the survival of the parasite within these short growing periods and to give basic information useful in planning control programs. Kerr (1955), in a series of experiments which were devised to establish the minimum maturing time of the worm in birds of different ages, showed that fertile eggs were recovered by fecal examinations as early as 30 days after infective eggs were ingested by 12-day-old chicks. Somewhat longer periods were required for older birds. Roberts (1937) found fertile eggs in the intestine as early as 27 or 28 days after infection with a 100 A. galli eggs. The 50-day period reported by Ackert would appear to be the average maturing time in somewhat older birds. No similar study on the minimum maturing time for eggs to develop to infectivity has been reported in the literature. Such work, together with temperature studies as related to development in the litter of brooder houses, is here reported.