E. Rautiainen et al., Monitoring antibodies to Mycoplasma hyopneumoniae in sow colostrum - a tool to document freedom of infection, ACT VET SC, 41(3), 2000, pp. 213-225
In a survey in Finland in 1995, 14919 colostral whey samples from 530 Farro
wing herds were analysed by a monoclonal blocking-ELISA to detect antibodie
s to Mycoplasma hyopneumoniae (M. hyopneumoniae). Antibodies were detected
in 274 (1.8%) samples and in 42 herds (7.9%). The median prevalence of sows
with antibodies in seropositive herds was 28.2% (range, 2.7-100%). Accordi
ng to clinical and pathological follow-up in finishing herds in 1996, all o
f the farrowing herds which were seronegative in 1995, were truly non-infec
ted with M. hyopneumoniae. In acutely infected herds, samples collected ear
lier than 2 h after farrowing were 3 times more likely to contain antibodie
s than samples collected 2-12 h after farrowing (odds ratio, 3.0; 95% CI, 1
.4-6.6). Repeated freezing or spoilage of the colostrum samples did not cau
se biologically relevant problems for the ELISA. Antibodies to M. hyopneumo
niae were shown to persist up to 3 years in some sows. As a conclusion, col
ostrum samples were very sensitive samples for the screening of herds for M
. hyopneumoniae infection and possibly also for a regular surveillance.