Submitted to: World Wide Web
Publication Type: Other
Publication Acceptance Date: 9/24/2012
Publication Date: N/A
Technical Abstract: This presentation reviewed maternal and non-maternal routes of exposure to ovine progressive pneumonia virus (OPPV), their relative impact on transmission, and factors that affect infection rates. Results of an experiment to investigate additive and dominance effects of the two most common haplotypes of a gene affecting susceptibility to ovine progressive pneumonia were discussed. Non-maternal exposure to OPPV during the preweaning period caused little infection, whereas maternal exposure infected about one-third of genetically-susceptible lambs. It was inferred that non-maternal exposure to OPPV is the primary cause of infection during the lifetime of breeding ewes, occurring after young uninfected ewes join an infected breeding flock. Traditional methods of establishing OPP-free flocks were reviewed. New procedures to establish OPP-free flocks and reduce genetic susceptibility to OPPV were proposed.