A seroepidemiological survey of adenovirus activity (types 1--3) at two Finnish calf rearing farms
Sihvonen, L.; Tuomi, J.
Acta Veterinaria Scandinavica 19(2): 192-203
1978
ISSN/ISBN: 0044-605X PMID: 211837 Document Number: 135094
Distribution of antibodies to serotypes 1, 2 and 3 of bovine adenovirus was studied at two calf rearing farms, one farm (A) operated as a closed, and the other (B) as an open herd. At farm A two serial studies were made, covering periods of six and nine months and including groups of 44 and 41 even-aged bull calves, respectively; at farm B at each bleeding calves of different selected age groups were included, 36 in all. Maternal antibodies against all types were common. With few exceptions they had disappeared at the age of five months. Unexpectedly, there was no sign of active infection at farm B. At farm A infection by type 3 was present during both studies, though affecting only a few calves; infections by types 1 and 2 definitely occurred only during the second study, and then extensively. The titres of type 1 and 2 antibodies were, on the average, higher (with highest titres 1/243 and 1/729, respectively) than those of type 3 (highest titre 1/27). The spread of infection within the groups was relatively slow. A possible causative participation of type 2 virus in a smaller epidemic of mild respiratory and enteric disease at farm A was suggested but not verified by the results. Maternal antibodies did not seem to give effective protection against infection.