Introduction: Mycoplasma bovis is one of the main pathogens involved in cattle pneumonia. Other mycoplasmas have also been directly implicated in respiratory diseases in cattle. The prevalence of different Mycoplasma spp. in cattle affected by respiratory diseases and molecular characteristics of M. bovis field strains were evaluated. Material and Methods: In total, 713 nasal swabs from 73 cattle herds were tested. The uvrC gene fragment was amplified by PCR and PCR products were sequenced. PCR/DGGE and RAPD were performed. Results: It was found that 39 (5.5%) samples were positive for M. bovis in the PCR and six field strains had point nucleotide mutations. Additionally, the phylogenetic analysis of 20 M. bovis field strains tested with RAPD showed two distinct groups of M. bovis strains sharing only 3.8% similarity. PCR/DGGE analysis demonstrated the presence of bacteria belonging to the Mollicutes class in 79.1% of DNA isolates. The isolates were identified as: Mycoplasma bovirhinis, M. dispar, M. bovis, M. canis, M. arginini, M. canadense, M. bovoculi, M. alkalescens, and Ureaplasma diversum. Conclusion: Different Mycoplasma spp. strains play a crucial role in inducing respiratory diseases in cattle.

Introduction: Several Mycoplasma species can cause severe diseases in ruminant hosts, some of which are the diseases listed by the World Organisation for Animal Health (OIE). The role of the Cervidae family in carrying and transmitting ruminant mycoplasma infections in Poland is unknown. Material and Methods: Antibody and antigen detection tests for the main mycoplasma species that can affect wild ruminants were performed on 237 samples (serum, nasal swab, bronchoalveolar lavage, and lung) collected from 161 animals during 2011-2014. The samples were obtained from a cull of healthy population of deer which included: 96 red deer (Cervus elaphus elaphus), 19 fallow deer (Dama dama), and 46 roe deer (Capreolus capreolus). Results: Serological screening tests revealed positive reactions to Mycoplasma bovis in one sample and to Mycoplasma capricolum subsp. capripneumoniae in three samples; however, these three samples were negative by immunoblotting. Other antibody and antigen detection tests demonstrated negative results. Conclusion: Currently wild cervids in Poland do not play a significant role in transmitting mycoplasma infections to domestic animals, but they remain a potential risk.

Introduction: Porcine pleuropneumonia inflicts important economic losses on most commercial herds. Detection of subclinical or chronic infection in animals still remains a challenge, as isolation and identification of A. pleuropneumoniae serotypes is difficult and quantification of the bacteria on agar plates is often almost impossible. The aim of the study was to develop and evaluate a serotype-specific quantitative TaqMan probe-based PCR for detection of serotype 2 in pig lungs, tonsils, and nasal swabs.Material and Methods: The primers were designed from the capsular polysaccharide biosynthesis genes of A. pleuropneumoniae serotype 2. PCR specificity and sensitivity were evaluated using reference strains and several other bacterial species commonly isolated from pigs.Results: The real-time qPCR for detection of A. pleuropneumoniae serotype 2 was highly specific and gave no false positives with other serotypes or different bacterial species of pig origin. The detection limit for pure culture was 1.2 × 10⁴ CFU/mL, for lung tissue and nasal swabs it was 1.2 × 10⁵ CFU/mL, and for tonsils - 1.2 × 10⁵ CFU/mL.Conclusion: The method can be used to serotype A. pleuropneumoniae isolates obtained during cultivation and to detect and identify A. pleuropneumoniae serotype 2 directly in nasal swabs and tonsil scrapings obtained from live pigs or lung tissue and tonsils collected post-mortem.

The objective of this study was to compare the efficacy of 2 different commercial Mycoplasma hyopneumoniae vaccines and porcine reproductive and respiratory syndrome virus (PRRSV) vaccines in regard to growth performance, microbiological and immunological analyses, and pathological observation from wean to finish (175 d of age). Pigs were administered M. hyopneumoniae and PRRSV vaccines at 7 and 21 d of age, respectively, or both at 21 d old and then challenged with both M. hyopneumoniae and PRRSV at 49 d old. Significant (P < 0.05) differences were observed between the 2 vaccinated challenged groups in average daily weight gain, nasal shedding of M. hyopneumoniae, M. hyopneumoniae-specific interferon-γ secreting cells, and macroscopic and microscopic lung lesions. Induction of interleukin-10 following PRRSV vaccination does not interfere with the immune responses induced by M. hyopneumoniae vaccine. The present study demonstrated that the single-dose vaccination regimen for M. hyopneumoniae and PRRSV vaccine is efficacious for controlling coinfection with M. hyopneumoniae and PRRSV based on clinical, microbiological, immunological, and pathological evaluation.

OBJECTIVE To evaluate the efficacy of 4 commercially available multivalent modified-live virus vaccines against clinical disease, viremia, and viral shedding caused by bovine viral diarrhea virus (BVDV) and bovine herpesvirus 1 (BHV1) in early-weaned beef calves. ANIMALS 54 early-weaned beef steers (median age, 95 days). PROCEDURES Calves were randomly assigned to 1 of 5 groups and administered PBSS (group A [control]; n = 11) or 1 of 4 commercially available modified-live virus vaccines that contained antigens against BHV1, BVDV types 1 (BVDV1) and 2 (BVDV2), parainfluenza type 3 virus, and bovine respiratory syncytial virus (groups B [11], C [10], D [11], and E [11]). Forty-five days after vaccination, calves were exposed simultaneously to 6 cattle persistently infected with BVDV and 8 calves acutely infected with BHV1 for 28 days (challenge exposure). For each calf, serum antibody titers against BVDV and BHV1 were determined before vaccination and before and after challenge exposure. Virus isolation was performed on nasal secretions, serum, and WBCs at predetermined times during the 28-day challenge exposure. RESULTS None of the calves developed severe clinical disease or died. Mean serum anti-BHV1 antibody titers did not differ significantly among the treatment groups at any time and gradually declined during the study. Mean serum anti-BVDV antibody titers appeared to be negatively associated with the incidence of viremia and BVDV shedding. The unvaccinated group (A) had the lowest mean serum anti-BVDV antibody titers. The mean serum anti-BVDV antibody titers for group D were generally lower than those for groups B, C, and E. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated differences in vaccine efficacy for the prevention of BVDV viremia and shedding in early-weaned beef calves.

OBJECTIVE To evaluate changes in systemic and ocular antibody responses of steers following intranasal vaccination with precipitated or partially solubilized recombinant Moraxella bovis cytotoxin (MbxA). ANIMALS 13 Angus steers with ages ranging from 318 to 389 days and weights ranging from 352 to 437 kg. PROCEDURES Steers were assigned to receive 500 μg of a precipitated (MbxA-P; n = 5) or partially solubilized (MbxA-S; 5) recombinant MbxA subunit adjuvanted with polyacrylic acid. A control group (n = 3) received the adjuvant alone. Each steer received the assigned treatment (1 mL/nostril) on days 0 and 28. Serum and tear samples were collected on days 0 (before vaccination), 14, 28, 42, and 55. Changes in MbxA-neutralizing antibody titers and MbxA-specific IgG concentrations in serum and tears and changes in MbxA-specific IgA concentrations in tears were measured. RESULTS Mean fold changes in MbxA-specific IgG concentration in serum and tears and MbxA-neutralizing antibody titer in tears for the MbxA-P group were significantly greater than those for the MbxA-S and control groups. Mean serum MbxA-neutralizing antibody titer did not differ among the 3 groups. Although the mean fold change in tear MbxA-specific IgA concentration differed significantly among the groups in the overall analysis, post hoc comparisons failed to identify any significant pairwise differences. CONCLUSIONS AND CLINICAL RELEVANCE Systemic and ocular immune responses induced by intranasal administration of the MbxA-P vaccine were superior to those induced by the MbxA-S vaccine. Additional research is necessary to determine whether the MbxA-P vaccine can prevent naturally occurring infectious bovine keratoconjunctivitis.