a1 The Experimental Parasitology Unit, Department of Zoology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
a2 The Experimental Parasitology Unit, Department of Zoology, University of Nottingham, University Park, Nottingham NG7 2RD, UK
Acquired immunity to Nematospiroidcs dubius was studied in the jird. It was found that a primary infection comprising one or two worms was highly immunogenic and the animals were resistant to challenge infection. Abbreviated infections in which the adult worms were eliminated by treatment with pyrantel also elicited strong resistance to challenge indicating that larval parasites as well as adults were involved in acquired immunity. A small proportion of adult worms completed their development in immune jirds and was recovered 11 days after the challenge infection. However, these worms were rapidly eliminated and few survived to day 16. Trickle infections in which the jirds were exposed to very low numbers of worms at regular intervals were unsuccessful in prolonging the duration of a primary infection. It was concluded that the remarkable sensitivity of the jird to infection with N. dubius should enable small quantities of fractionated parasite derived material to be screened for immunogenicity in this host.