Cross-Sectional Study on the Prevalence of PCV Types 2 and 3 DNA in Suckling Piglets Compared to Grow-Finish Pigs in Downstream Production.

Vertical transmission is a consistently discussed pathway of porcine circovirus type 2 (PCV2) and porcine circovirus type 3 (PCV3) transmission in pigs. To evaluate the presence of PCV2 and PCV3 in piglets, we collected tissue samples from 185 piglets that were crushed within the first week of life from 16 farms located in Germany and Austria. Pooled samples consisting of thymus, inguinal lymph node, myocardium, lung and spleen were examined for PCV2 and PCV3 by qPCR. Furthermore, oral fluid samples (OFS) from grow−finish pigs were collected and examined the same way. In piglets, PCV2 was highly prevalent (litters: 69.4%; piglets: 61.6%), whereas PCV3 prevalence was low (litters: 13.4%; piglets: 13.0%). In total, 72.6% and 67.2% of all collected OFS were PCV2 or PCV3 positive, respectively. Sow vaccination against PCV2 was identified as a protective factor concerning PCV2 in piglets (OR: 0.279; CI: 0.134−0.578; p < 0.001), whereas the porcine reproductive and respiratory syndrome virus (PRRSV) vaccination of sows was identified as a protective factor concerning PCV3 in piglets (OR: 0.252 CI: 0.104−0.610; p = 0.002). Our results show that PCV2, but not PCV3, is ubiquitous in suckling piglets and that early PCV3 infections might be modulated by PRRSV−PCV3 interaction. However, the ubiquitous nature of both viruses in older pigs could be confirmed.

Cross-sectional study on the in-herd prevalence of Mycoplasma hyopneumoniae at different stages of pig production.

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.

Evaluation of the Efficacy of a Vaccination Program against Actinobacillus pleuropneumoniae Based on Lung-Scoring at Slaughter.

Porcine pleuropneumonia is of serious concern regarding lung health in pig production. Besides optimizing hygiene and pig management, specific vaccination against the causative agent, Actinobacillus pleuropneumoniae, is an important tool in the fight against this disease. As porcine pleuropneumonia may present with different clinical courses of disease, it is not always easy to objectively assess herd lung health state or to monitor improvements following specific therapeutic or prophylactic measures. Here, the effects of specific vaccination on lung health in a chronically diseased farrow-to-finish farm in Lower Austria experiencing an acute episode were monitored by means of an app-based electronic tool, enabling the scorers to document lung pathologies real-time at slaughter. At the time, when vaccination measures took effect, percentages of lungs affected by dorsocaudal pleurisy had decreased from 43 to 5 and the APP-index from 1.2 to 0.1, respectively. But not only pleurisies were diminished, also incidences and severities of bronchopneumonic alterations had dramatically decreased and exhibited interesting trends when set in connection to clinical signs. Overall, vaccination measures against Actinobacillus pleuropneumoniae proved to be very effective in restoring herd lung health.

Cystoisospora suis Control in Europe Is Not Always Effective.

After introduction of the anticoccidial toltrazuril for the metaphylactic treatment of suckling piglet coccidiosis, only few field evaluations on the effect of treatment against the causative agent, Cystoisospora suis, were performed. In 2018, a field study was conducted to detect the presence of the parasite on pig farms in four different European countries, and to evaluate management parameters possibly associated with infection and disease. A total of 49 farms from Austria, the Czech Republic, Germany and Spain were included. Repeated pooled fecal samples from 603 litters were taken in the 2nd and 3rd week of life. Samples were examined by autofluorescence for the presence of C. suis, and fecal consistency was scored. For each farm a questionnaire was provided to document management and treatment history. Feces scored as diarrhoeic were not significantly more often positive for C. suis than non-diarrhoeic feces but samples from litters with previously reported occurrence of diarrhea were significantly more often positive (p = 0.000). Pasty feces were significantly more often positive than those of other consistency (p = 0.005). Overall, 71.4% of the farms and 50.1% of the litters were positive for C. suis at least once. The prevalence on the farms reached up to 100%. Diarrhea was seen in samples from 53.1% of the farms (9.6% of the litters). Cystoisospora suis was diagnosed on 80.8% of the farms with vs. 60.8% of those without diarrhea. Toltrazuril was applied on 30 farms, and of these 53.3% had diarrhoeic samples and 66.7% were positive for C. suis vs. 19 farms that did not use toltrazuril with 52.6% diarrhoeic and 79.0% C. suis positive samples (p > 0.05). Only on two farms a disinfectant with activity against coccidia was used, and C. suis was not detected there. Current control of C. suis appears to be insufficient on the majority of the examined farms. These findings highlight the importance of correct application of medication, and an effective hygiene management. To maintain effective parasite control, efficacy monitoring of the control measures should be implemented.

Clinical efficacy of two vaccination strategies against Mycoplasma hyopneumoniae in a pig herd suffering from respiratory disease.

BACKGROUND: A randomised field trial was conducted on an Austrian farrow-to-finish farm for one year to compare the efficacy of two commercial Mycoplasma hyopneumoniae vaccines. 585 piglets either received the one-shot formulation in group 1 (Hyogen®, 23.9 days of age) or a two-shot vaccine (Stellamune® Mycoplasma, 4.3 and 24.0 days of age) in group 2. Assessment of vaccine efficacy was evaluated by regression analyses through cough monitoring from nursery to slaughter, average daily weight gain from inclusion to slaughter, antibiotic treatment rate (ATR), mortality rate, and lung lesion scoring at slaughter. RESULTS: In general, coughing was more frequent during late nursery and finishing. No significant differences were found in the coughing index (0.02 vs 0.03) and mean average daily weight gain (560 vs 550 g) between the two groups. ATR was higher in group 2 (3.8 vs 9.6%). At the slaughterhouse check, significant differences in the prevalence of bronchopneumonia (62.9 vs 71.2%) could be found. Extension of lung lesions was also significantly lower in group 1 in terms of enzootic pneumonia (EP) values (p = 0.000, z = - 4.269). There were no significant differences in the rate of scarred lungs (20.0 vs 24.0%) or those affected by dorsocaudal pleurisy (36.8 vs 34.3%). CONCLUSIONS: This trial demonstrated that Hyogen® was superior to Stellamune® Mycoplasma in reducing (I) the prevalence of bronchopneumonic lungs and those affected by cranioventral pleurisy, (II) the extension and severity of EP-like lung lesions, and (III) the rate of antibiotically treated animals against respiratory disease.