An experimental epidemiological study of Talfan virus infection in pigs

Abstract

Talfan virus was introduced experimentally into a small herd of MD pigs by the oral dosing of one litter of piglets with virus cultivated in PK cells. Serum samples from all pigs in the herd were examined for Talfan neutralizing antibodies at monthly intervals for 8 months, and virus isolation from rectal swabs was attempted at weekly or monthly intervals for the same period. Samples from the colon were collected for virus isolation from pigs at slaughter. The infection produced diarrhoea in suckling piglets and in one gilt, and nervous signs in suckling piglets, one gilt and one boar during the first 5 weeks of the experiment. Thereafter, clinical disease attributed to Talfan virus was not apparent. In the early (epidemic) phase of the infection, pigs of all ages excreted virus for a period up to 8 weeks and developed circulating antibodies which persisted at fairly high levels throughout the experiment. Piglets born one month or more after the introduction of Talfan virus excreted virus only after weaning and developed a circulating antibody response to Talfan in the post-weaning period.