In addition, Amin (1980, 1987) and Kennedy (2006) analyzed the ecology of intermediate hosts and showed that in warm temperatures, parasite development increases as cystachanths (the infective stage to the definitive host
) in the intermediate host; a greater proportion of gravid female worms are found in the definitive host
during the summer; and the definitive host
consumed more infected intermediate host in the summer, resulting in higher transmission rates.
The occurrence of nematode larvae in fish is not obligatory for completing its life cycle, however, they appear to be important ecologically by acting as paratenic hosts in causing infection in the definitive host
Wild canids (e.g., foxes and coyotes), dogs, and (less commonly) cats act as definitive hosts
, which harbor adult parasites in the small intestine without apparent clinical disease.
Cercariae penetrate the second intermediate host and form a resting cyst (also known as a metacercariae --Figure 2) in the host's muscle tissue, where they await a predation event that will transfer the parasite from the second intermediate host to the definitive host--the definitive host
eats the second intermediate host, thus completing the parasite's life cycle.
In this study, we did not seek to identify the definitive host
of these haemogregarines.
PHSKC recommended restricting access to the tree and surrounding areas until it could be appropriately cleaned and consulting with a veterinarian about implementing regular deworming for their dog, because canines can be a definitive host
However, the goal of that study  was to determine if birds were the definitive host
Gammarids regularly harbor manipulative acanthocephalan parasites that modify their anti-predator behavior in ways that potentially increase the probability of trophic transmission to their definitive hosts
. We investigated the impact of temperature on gammarids infected by two acanthocephalan parasites, Pomphorhynchus tereticollis and Polymorphus minutus.
parva, are more susceptible to environmental perturbations, which makes it possible to use them as reliable biological tags of the reestablishment of the ecosystem's trophic chain, as they require the intervention of an intermediate host, in this case a rodent, serving as prey for its definitive host
. In the Iberian Peninsula, the biological cycle of T.
Humans get infected through contact with the definitive host
or ingesting contaminated soil, water, and vegetables .
Type host: Natural definitive host
: Buteogallus anthracinus.
The adult worm lives in the intestine of the definitive host
which includes dogs and other carnivorous animals.
 Man is the definitive host
; animal or reservoir host is not known.
relationships of the helminth parasites of the deer mouse, Peromyscus maniculatus, in the Bonneville Basin of Utah.