GROWTH AND FECUNDITY OF OESOPHAGOSTOMUM-DENTATUM IN HIGH-LEVEL INFECTIONS AND AFTER TRANSPLANTATION INTO NAIVE PIGS

This experiment was designed to examine the growth, proportion of stag es, and fecundity of an Oesophagostomum dentatum population by transpl antation of a known small number of worms from a high-density populati on into helminth-naive recipient pigs. Approximately 1,500 4-week-old worms [69% fourth-stage larvae (L(4)), 31% adult worms] were transplan ted into each of 5 recipient pigs (group B), and these pigs, along wit h a group of 5 high-level-infection control pigs (group C), were kille d at 4 weeks after transplantation to determine and compare the worm b urdens. By 2 weeks after transplantation and throughout the experiment , fecal egg counts of group B exceeded those of group C and the fecund ity of the worms was higher, though not statistically significantly so , in the transplanted worms. In the recipient pigs, all worms (approx. 70% establishment) had developed to the adult stage and were signific antly longer than worms recovered from the group C pigs.