04-06-2012, 01:34 PM
Breeding for disease resistance :Some examples
Breeding for disease resistance.ppt (Size: 131 KB / Downloads: 57)
Cost of disease
Economic consequences of disease include :
Loss of rabbit meat sales (mortality, lower growth rate) Increased culling rate Cost for veterinary treatment
Increased work in animal management (culling, treatment)
Definition of disease resistance
Infection
Different mechanisms of the pathogen and of the host
Depending on the stage of infection the resistance appears as :
Prospect for genetic improvement of disease resistance
Interest of breeding for disease resistance
Depend on the efficiency of the non genetic approach
(environment, vaccination, treatment, culling of infected animal
Salmonella in sheep (abortus ovis) : efficient vaccines are available
Scrapie in sheep : no vaccination and no treatment
Selection is very appealing in this case
Conclusion
Susceptibility to disease is influenced by genetic factors
Estimation of heritability are medium, similar to the values
of production traits .
Correct definition of resistance measurement
Cost of resistance measurement
Consequences of selection on theses trait (resistance to other disease,
resistant animals remains diffusers of pathogens) .