The evolution of sheep immunity in response to nematode infection

Cameline Orlendo

Friday 11th November, 2016 16:00-17:00 Maths 204

Abstract

Nematode infections in livestock affect ruminants like cows, sheep pigs, and goats. These macro-parasites mature and reproduce within the host's abomasum. Once infected the host experiences a relative protein deficiency that prohibits its growth and also lowers its productivity. In some extreme cases, where the animal is heavily infected, the infection can lead to the host's death . These effects incur huge losses to the animal production sector. Many  hosts  mount  relatively  weak levels of immunity in response  to the infection,  whilst  only a few hosts mount a higher immune  response required to lower the infectivity of the parasites. The  immune  responses  mounted  against  the  infective  agents  have moderately to highly heritable levels,  hence  the  host' s immunity  is shaped  by  evolution. The  variance  in the  immune  strengths amongst  the  host  population contradicts the Darwinian natural selection  theory which  states that evolution shapes organisms  to be better adapted to their  environments which in this case is to produce  the best immune  responses against  the infection.  In the disease infection system,  there  is a collective larval-pool  thus  the  few individuals  mounting  a higher  immune  response  may  end  up  bearing a  greater  burden  in  regulating   the  parasite numbers.   We study the consequence of sheep displaying varying immunity strategies in the nematode infection of sheep.

Add to your calendar

Download event information as iCalendar file (only this event)