ASCARIDIA-GALLI POPULATIONS IN CHICKENS FOLLOWING SINGLE INFECTIONS WITH DIFFERENT DOSE LEVELS

In all, 3 groups of 20 Lohman Brown chickens aged 1 day were orally in fected with doses of 100, 500, or 2,500 embryonated Ascaridia galli eg gs, respectively. After 8 weeks, egg counts (eggs per gram of feces, E PG) were determined for all animals prior to slaughter. The gastrointe stinal tracts were examined for the presence of adult and immature sta ges of A. galli. All groups had roughly similar worm burdens and, henc e. significantly different establishment rates of 14.2%. 2.9%, and 0.5 %, respectively. A significantly lower mean female worm burden was see n in the high-dose group (P = 0.02), which also showed a significantly lower level of egg excretion (P = 0.01). However, fecundity (EPG per female) did not significantly differ between the groups (P = 0.55). Th e mean lengths of adult worms as well as the weight of the mean worm b urdens were significantly smaller in the high-dose group. This study d emonstrated that single infections with varying doses of A. galli eggs influenced the establishment rate, sex ratio, egg excretion, and worm size and weight but not the worm fecundity.