The excystment, growth and reproduction of Acanthoparyphiutn spinulosum Johnston, 1917 (Trematoda) in chicks fed various diets

Abstract

Studies have been made of the growth and excystment of a trematode, Acanthoparyphium spinulosum, in chicks fed on various denned diets.Day-old chicks were fed metacercariae and maintained on deficient as well as complete rations for periods up to 20 days. The excystment rate was determined by the number of worms that were recovered from the metacercariae. The largest number of worms were recovered from chicks that received a normal diet with starch as the sole carbohydrate source. The smallest percentage of parasites was found in birds that had received a normal diet with sucrose serving as the carbohydrate source. About 25 % were recovered from chicks fed several other diets.The trematodes developed and grew well in vitamin A deficient chicks; there was a large number of intra-uterine ova observed in worms from these hosts. Acanthoparyphium spinulosum from chicks fed a ‘no vitamin D’ diet grew at a normal rate until the 6th day; after this they grew more slowly than 6-day-old worms in chicks fed the ‘no vitamin A’ diet.The lengths of worms from birds deprived of all vitamins differed little from those of the parasites recovered from the chicks deficient in vitamin D. The largest worms were obtained from chicks fed a complete diet with starch as the sole carbohydrate source.Parasites from chicks fed a diet 50 % deficient in carbohydrates (with sucrose as the carbohydrate) developed normally.Worms also developed in chicks fed a ‘no protein’ diet with starch and a ‘no protein’ diet with sucrose. A deleterious effect on ova production was observed in worms from both these groups.Metacercariae developed in chicks fed a ‘no carbohydrate’ diet, but no mature worms were recovered due to the reduced life of the host. Starvation of the hosts produced small worms containing few intra-uterine ova.The growth curve of A.spinulosum was plotted and compared with Echino-paryphium flexum.This investigation was supported in part by U.S. Public Health Service Grant UI-00202, and by a grant-in-aid of research by the Society of the Sigma Xi, New Haven, Connecticut.