Detection and genetic characterization of porcine circovirus type 2 (PCV2) in pigs from Croatia.

Porcine circovirus type 2 (PCV2) from the Circoviridae family has recently been associated with two serious diseases of swine, post-weaning multisystemic wasting syndrome (PMWS) and porcine dermatitis and nephropathy syndrome (PDNS). During 2002, several outbreaks of clinical disease in pigs with weights ranging from 10 to 70 kg occurred on four farms in different locations in Croatia. The signs were consistent with PMWS and PDNS. Apart from progressive weight loss, pneumonia and/or diarrhoea, multifocal erythematous skin lesions and dermal necrosis were also observed. The PCR results obtained from PCV2 specific oligonucleotide primers confirmed a PCV2 infection. In addition, archive samples that were classical swine fever virus positive and derived from domestic pigs during an outbreak in 1997 were included in this study and one out of the three isolates was found to be positive for PCV2. For a better epizootiological understanding, genetic typing of representative isolates was carried out and compared with available isolates reported in the GenBank databases.

Distribution of airborne bacteria in swine housing facilities and their immediate environment.

This paper describes a bacteriological analysis of air samples taken from swine housing facilities and the immediate environment. The air volume of the samples was pre-programmed by a standard air sampler (MAS-100, Merck) and was directly impacted onto the bacteriologic agar surface (Petri dishes, standard diameter of 90 mm). The bacterial contamination in forty-eight samples was 2.59 x 10(5) CFU/m3 (ranging from 8.46 x 10(4) to 5.30 x 10(5) CFU/m3). Potentially pathogenic bacterial agents predominated in all samples (100%), while primarily pathogenic bacteria were isolated in a minor proportion of samples (33%-66%). Airborne bacterial contamination in samples (N = 16) obtained from emptied facilities ranged from 1.8 x 10(3) CFU/m3 (that is, after coarse mechanical washing) to 0.8 x 10(2) CFU/m3 (upon completion of disinfection). Control measurements at different locations and distance from the farm (N = 32) pointed to the presence of non-pathogenic airborne bacteria, ranging from 1.55 x 10(2) to 3.70 x 10(2) CFU/m3. The results of this preliminary study showed that the emission of potentially pathogenic bacteria from animal housing facilities to the immediate farm environment via aerosol was very low.

Comparison of ELISA and 2-META assays used in serological diagnosis of infection with Actinobacillus pleuropneumoniae serotypes 2 and 4-7 in breeding pigs in Croatia.

The aim of the study was to compare the results of ELISA and 2-META assays in serological diagnosis of swine pleuropneumonia in breeding pigs of different ages. A total of 874 sera were examined for the presence of antibodies against Actinobacillus (A.) pleuropneumoniae serotype 2. The sera had been taken from 437 gilts (aged approximately 6 months), 334 sows (> 2 years of age) and 104 boars (1-2 years). Sixty-nine sera of the gilts and sows, and 46 sera of the boars were also examined for the presence of antibodies against A. pleuropneumoniae serotype 4-7. Sera from the youngest age group (gilts) showed the highest agreement between the results obtained by the two assays, with a kappa value of 0.633 and 0.437 for detection of antibodies against A. pleuropneumoniae serotype 2 and 4-7, respectively. The lowest agreement of the two assays was recorded in the oldest age group (sows), with a kappa value of 0.128 and 0.199 for detection of antibodies against A. pleuropneumoniae serotype 2 and 4-7, respectively. Boars were older than gilts and younger than sows. In this group of animals, agreement between the results of the two assays was inferior to that found in gilts and superior to that recorded in sows.

Mycoplasmal pneumonia in pigs in Croatia: first evaluation of a vaccine in fattening pigs.

The immunoprophylaxis of mycoplasmal pneumonia of swine (MPS) caused by Mycoplasma hypopneumoniae was investigated for the first time in fattening pigs in Croatia. The incidence of MPS was monitored in pigs weighing on average 27.5 kg (12 weeks old) after immunization with a M. hyopneumoniae vaccine. Of 350 pigs in each group, in the nonvaccinated group 55 animals (15.7%) were affected by pneumonia and 11 (3.1%) died of consequences of pneumonia, whereas in the vaccinated group 20 pigs (5.7%) were affected by pneumonia without any death due to the infection. In the nonvaccinated group 44% more pigs were individually treated with antibiotic, and these animals received in-feed therapy for more than 1/4 of the fattening period. Vaccinated pigs gained weight faster, at the rate of 0.745 kg/day (or 82 g/day more) than control animals. The mean score of lung lesions due to M. hyopneumoniae was 10.51 in the control pigs and only 0.54 in the vaccinated animals. The total tissue alterations on lungs due to M. hyopneumoniae, Pasteurella multocida and/or Actinobacillus pleuropneumoniae expressed as the mean-score were 13.21 in the control group and 2.98 in the vaccinated group. According to the results of evaluation of the M. hyopneumoniae vaccine in the field, the vaccine appeared to provide an adequate immunity in fattening pigs but was less effective when administered to younger pigs at 1-3 weeks of age.