No Adaptation of Roundworms to Resistant Hosts
نویسندگان
چکیده
A genetically diverse population of Haemonchus contortus was serially passaged through Merino hosts bred for either increased or decreased resistance to the parasite. After 30 parasite generations, the resulting nematode sub-populations were compared with each other and with the foundation population, by infecting lines of the selected sheep and measuring the resulting faecal egg counts (FECs) and packed cell volume declines (PCVDs). There was no evidence from either FECs or PCVDs, that parasites passaged through resistant hosts had changed in response to host selection.
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