We isolated the causative organisms from bronchoalveolar lavage fluid (BALF) in the cattles with refractory pneumonia that had not been cured by primary care, and investigated the drug susceptibility and the prognosis of the cases. The major isolates were Mycoplasma bovis (41.7%), Trueperella pyogenes (29.2%), Pasteurella multocida (26.4%), and Mannheimia haemolytica (8.3%). 62.5% of the cattle were cured by antimicrobial therapy based on the drug susceptibility of BALF-derived bacteria. On the other hand, a high proportion of multidrug-resistant and highly drug-resistant M. bovis was isolated from the BALF of cattle with a poor prognosis, and the choice of susceptible antimicrobial agents was very limited. Other isolates were also susceptible in the good prognosis group but were resistant to most antimicrobial agents in the poor prognosis group, making treatment very difficult. This study revealed that the increase in the number of resistant bacteria is decreasing the cure rate of pneumonia.

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We investigated the effect of both duration from vaccination to parturition in pregnant sows and colostral restriction during 6 h after birth for neonate piglets on the level of maternal antibodies for classical swine fever (CSF) vaccine in suckling piglets. In this study, piglets delivered from 3 pregnant sows vaccinated with CSF and 2 unvaccinated pregnant sows were used, and the serum CSF neutralizing antibody titeres in piglets with colostral restriction during the suckling period was significantly lower than those without the restriction. In the piglets with restricted colostrum intake, the group with a period from vaccination to parturition of 21 days had a significantly lower CSF antibody titer during the experimental period than the group of more than 161 days. The percentage of piglets testing positive for CSF antibodies was 0% at 14 and 21 days after birth in the group with short a short period (21 days) from vaccination to parturition and colostral restriction. Our results indicate that both of the timing of the initial vaccination of unimmunized pregnant sows and the restriction of colostrum have a clear effect on the level of maternal CSF antibodies in suckling piglets.

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