Phenotypic, molecular and genomic characterization of Actinobaculum suis isolated from swine in Brazil.

Urinary tract infections (UTI) are considered one of the most important diseases of sows due to its close relationship with reproductive problems such as reduced litter size, increase in the rate of return to estrous, vulvar discharge, abortion, mastitis and anestrus. Actinobaculum suis is one of the main agents involved in porcine urinary tract infection and is responsible for the most severe and fatal cases in sows. In the present report, 23 A. suis strains isolated from a sow and boars in Brazil were identified by PCR and further characterized by broth microdilution, molecular typing by pulsed-field gel electrophoresis (PFGE), single-enzyme amplified fragment length polymorphism (SE-AFLP), and whole-genome sequencing. All strains were sensitive to ceftiofur, linezolid, nitrofurantoin, quinupristin-dalfopristin and vancomycin. Ciprofloxacin, daptomycin, lincomycin, erythromycin and tylosin resistance was observed in 100% of tested strains. Tetracycline and tigecycline also presented high resistance rates (87% and 30.4%, respectively). PFGE with eight different restriction enzymes and three programs did not enable strain characterization; however, all strains were typed by SE-AFLP that clustered strains according to their origin, thus proving an effective tool for A. suis genotyping. Whole-genome sequencing and comparative analysis enabled species differentiation from closely related genus. This is the first report of genomic characterization of A. suis.

Molecular survey of Cytomegalovirus shedding profile in commercial pig herds in Brazil.

INTRODUCTION: Porcine cytomegalovirus (PCMV) causes rhinitis in both young and older pigs. The present study describes the detection and characterization of shedding profiles of PCMV in nine farrow-to-finish Brazilian swine herds. METHODOLOGY: Tonsil swabs from sows, nursery and grow-finish pigs of nine farrow-to-finish commercial herds (n = 756) were evaluated for the presence of PCMV by PCR. RESULTS: The virus was detected in all herds. Positive samples were concentrated in piglets of ages varying from 40 to 60 days (nursery phase), while none of the sows were positive for PCMV detection. CONCLUSIONS: These findings corroborate the literature regarding PCMV worldwide distribution, and introduce the first report of PCMV shedding profile in Brazilian pig farms.

Actinobaculum suis detection using polymerase chain reaction.

Actinobaculum suis is an important agent related to urinary infection in swine females. Due to its fastidious growth characteristics, the isolation of this anaerobic bacterium is difficult, thus impairing the estimation of its prevalence. The purpose of this study was to develop and test a polymerase chain reaction (PCR) for the detection and identification of A. suis and then compare these results with traditional isolation methods. Bacterial isolation and PCR were performed on one hundred and ninety-two urine samples from sows and forty-five preputial swabs from boars. The results indicate that this PCR was specific for A. suis, presenting a detection limit between 1.0 × 10(1) CFU/mL and 1.0 × 10(2) CFU/mL. A. suis frequencies, as measured by PCR, were 8.9% (17/192) in sow urine samples and 82.2% (37/45) in preputial swabs. Assessed using conventional culturing techniques, none of the urine samples were positive for A. suis; however, A. suis was detected in 31.1% (14/45) of the swabs. This PCR technique was shown to be an efficient method for the detection of A. suis in urine and preputial swabs.