Forsøksdyr: Gastrointestinal nematode cattle donors for in-vitro experiments

Godkjenningsdato 15.01.2020

Godkjenningsperiode 16.01.2020-01.06.2020

Alternative treatments to parasitic gastrointestinal nematode infections in cattle are required due to the development of anthelmintic resistance. Therefore, the anthelmintic efficacy of new bioactive compounds against cattle nematodes needs to be assessed with laboratory methods.
These methods will be applied on the free-living stages of the nematodes (i.e. eggs and larvae) and the adult worms, which can only be retrieved after the host is infected.

In this set up, we will orally infect 2 donor calves of 2.5 - 3 months of age with the gastrointestinal nematode Ostertagia ostertagi up to a subclinical level of parasitic gastroenteritis to propagate the parasite. The excreted eggs and larvae will be used for the in-vitro assessment of the anthelmintic efficacy of pine and spruce bark extracts. The intentional infection will remain subclinical to avoid a strong immune response from the donors and to allow for extended parasitic egg excretion. Additionally, this will not compromise the welfare of the animals any more than free grazing individuals. Blood samples will be used for the detection of circulating antigens/antibodies of the parasite for development of infection detection method. The donors will be closely monitored for welfare reasons and within controlled facilities to prevent any external contamination and maintain the monospecific infection.