Comparison of three common methods of lung lavage in healthy pigs.

Bronchoscopic, endotracheal and transtracheal lung lavage were evaluated in 38 healthy pigs taken from a nucleus herd in a good state of health with respect to their applicability in practice and the traceability of bacteria, cellular parameters and the antimicrobial peptide PR-39 in the respective lavage fluid samples. The total cell count, qualitative morphological cellular characteristics as well as PR-39 could be determined in all lavage fluid samples, while quantitative cell differentiation was not possible in endotracheal lavage samples. The comparison of the three methods resulted in a higher proportion of polymorphonuclear neutrophil granulocytes (PMNs) and higher concentrations of PR-39 in transtracheal samples. For this reason different valuation standards with respect to PMNs and PR-39 concentrations are presupposed for transtracheal lavage samples. The occurrence of pavement epithelial cells as well as the number of contaminating bacterial species per sample was the lowest in transtracheal lavage. Mycoplasma hyopneumoniae polymerase chain reaction appeared to have the highest diagnostic sensitivity in combination with bronchoscopic lavage. In conclusion, bronchoscopic and transtracheal lavage were considered to be more appropriate for bacteriological and cytological diagnostics than endotracheal lavage.

Respiratory disease markers in porcine bronchoalveolar lavage fluid.

In bronchoalveolar lavage fluid (BALF) of pigs originating from different herds bacteria, cells and the antibacterial peptide PR-39 were examined to gain information about the lung health status. In a high health nucleus herd 56% and in low health herds 20-100% of the examined pigs were found positive for potentially pathogenic bacteria. Based on these findings, a novel definition for bacterial respiratory tract disease was established using an 8% cut-off for the relative number of neutrophils in bronchoscopic and a 40% cut-off in transtracheal BALF in combination with the occurrence of potentially pathogenic microorganisms. The antibacterial peptide PR-39 was highly correlated to this definition of respiratory disease. An assessment of the bacteriological respiratory health status appears to be possibly based on the determination of PR-39 concentrations in BALF using different cut-off values according to the lavage method (2.5 nM for bronchoscopic and 5 nM for transtracheal BALF).

Serological diagnosis of Aujeszky's disease: a comparison between reactions of blood samples from sows and their offspring.

Blood sera from sows and their piglets were compared for their suitability for the serological diagnosis of Aujeszky's disease. Within a few days after parturition, blood and colostrum samples were collected from a total of 104 sows from 8 different gI-vaccinated breeding herds. Three piglets of each litter were bled simultaneously with their mother and again 3 weeks later. All 416 sera reacted positively in the screening for vaccination-induced antibodies. Using the gI ELISA, the sera of 16 sows and their offspring reacted positively, while 86 sows and their piglets reacted negatively and 2 sows and their piglets showed reactions near the test-cutoff. By testing piglets from another 1,300 sows in 37 farms, the practicability of the proposed method was proved. Blood samples were taken at intervals of 4 to 6 weeks from piglets of all sows, which had farrowed in the meantime. Within a six to nine months period, the serological status of a breeding herd could be established.