Cross‐sectional study on the in‐herd prevalence ofMycoplasma hyopneumoniaeat different stages of pig production

Abstract

Background: A cross-sectional study was carried out to assess the prevalence of Mycoplasma hyopneumoniae infections before vaccination in 3-week-old piglets and to gain information about infection dynamics. Methods: In 13 German and three Austrian farms with a known history of enzootic pneumonia, 790 piglets and 158 sows were sampled (blood samples, tracheobronchial swabs [TBS] [piglets], laryngeal swabs [LS] [sows]), and 525 pen-based oral fluids (OFs) were collected in growing and fattening pigs. Laboratory diagnostics included enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (PCR) analyses. Results: Antibodies to M. hyopneumoniae were present in 87.5 per cent of all herds. Seroprevalence ranged from 0.0 to 100.0 per cent and 0.0 to 88.0 per cent in sows and piglets, respectively. M. hyopneumoniae-deoxyribonucleic acid (DNA) was present in 3.8 and 0.4 per cent of LS and TBS, respectively. Gilts had a 10.9 times higher chance being M. hyopneumoniae PCR-positive than older sows. In 75.0 per cent of all farms, M. hyopneumoniae-DNA was present in OFs. Detection rate was significantly higher in OFs of 20-week-old than in younger pigs (p < 0.001). Conclusion:Results indicate that M. hyopneumoniae infections of the lower respiratory tract in piglets are rare but highlight the role of gilts in maintaining infection in the herd. Collecting OFs seems promising for surveillance, if coughing occurs simultaneously.

Influence of parity and reproductive stage on the prevalence of Mycoplasma hyopneumoniae in breeding animals in belgian farrow-to-finish pig herds

“…This highlights the need to develop DIVA compliant vaccines against M. hyopneumoniae [ 31 ]. In this study, gilts were significantly more often infected with M. hyopneumoniae , and gilts had more often M. hyopneumoniae -specific antibodies compared to sows, which is in line with previous findings [ 3 , 10 , 12 , 13 ]. However, in most studies M. hyopneumoniae PCR prevalence or seroprevalence was investigated in breeding animals only to draw conclusions on their offspring [ 5 , 32 ].…”

“…Between the farms the variation of M. hyopneumoniae PCR prevalence was high. Although M. hyopneumoniae circulation was suspected, the PCR prevalence was low or even zero in the breeding animals on some farms [ 13 ]. For the seroprevalence on the other hand, the percentages were high and there was less variation between farms.…”

“…However, in most studies M. hyopneumoniae PCR prevalence or seroprevalence was investigated in breeding animals only to draw conclusions on their offspring [ 5 , 32 ]. Only a few studies investigated the PCR prevalence or seroprevalence in breeding animals in a larger number of herds [ 11 , 13 ]. Furthermore, swabs for the detection of M. hyopneumoniae DNA were mostly taken in the upper respiratory tract using PCR analysis while the sensitivity of TBS is higher [ 20 ].…”

“…Several studies have focused on the link between sow parity and the presence of M. hyopneumoniae in sows. Most studies reported a higher PCR prevalence or seroprevalence of M. hyopneumoniae in gilts and/or young sows [ 3 , 10 , 12 , 13 ], while others did not find such a correlation [ 14 ]. Besides the parity also the time point (TP) in the reproductive cycle may influence the presence of M. hyopneumoniae , especially in gilts [ 15 ].…”

Evaluating the role of gilts in the kinetics ofMycoplasma hyopneumoniaeoutbreaks

“…study of 10 Flemish breeding herds revealed an M hyopneumoniae detection level between 0 and 43.8 per cent in breeding animals. 20 However, similar to the findings of Deffner and colleagues' study, 17 the gilts sampled in this study were significantly more likely to test positive for M hyopneumoniae DNA than older sows. 20 The difference between the findings of Deffner and colleagues' study and those of previous studies might be explained by the fact that they only sampled clinically healthy pigs.…”