Erysipelothrix rhusiopathiae  is a small rod,gram-positive and facultative bacteria . Its distribution  ]is ubiquitous, as commensal or associated to disease in human and animals, being swine an important reservoir.The economic losses due E. rhusiopathiae infections in swine production affect principally adult animals worldwide.Three clinical forms are described in humans: the localized cutaneous form (erisipeloid), generalized cutaneous and septic form with endocarditis and arthritis. These infections are generally associated to handling of infected animal tissues and skin lesions. Thus, it is an occupational hazard mainly associated to slaughterhouse employees.

Thirty to fifty percent of healthy swine have E. rhusiopathiae in tonsils and lymphoid tissues and they are important source of infection during outbreaks due to nasal discharges, urine and feces contaminated. Considering the absence of data about this important pathogen in central western of Brazil this study aimed to describe the prevalence of    E.rhusiopathiae in healthy swine at Mato Grosso State - Brazil.

The number of samples was estimated according to the program EPI-INFO 2008 using 14% prevalence estimated from the media of results of  other studies, 6% error and 1.069,301 million animals in the state according to the pigs farmer's association of the State of Mato Grosso (ACRISMAT). Samples were collected from swine tonsils in three slaughterhouses under federal inspection from June 2005 to July 2008, 30 samples in the first year and three collections of 30 samples were collected in each year, 310 samples were collected in total.  The collection of batches was carried out according to the sequence of slaughter, collecting only 10 samples per batch. One gram of tonsil tissue were cultivate in 20 mL of try soy broth with violet crystal, tris and tween 80 as a pre-enrichment according to Yamazaki (2006), during 48 hours at 37 degree Celsius. DNA was extracted from 2 mL, by adding proteinase K followed by phenol-chloroform treatment and isopropanol precipitation. DNA was dissolved in 20 microliters of ultrapure water. To detect E. tonsillarum, PCR reaction was performed with 0.16 pmol each primer MO101 and ERS-1S according Yamazaki (2006), 2.4mM MgCl2, 10X of TaqBuffer, 0.2mM of each DNTP, 2 U Taq DNA polymerase (Fermentas ) 1,5 microliter of DNA and ultrapure water to 25 microliters finalvolume. Thermal cicling condition was 94 degreeC/4min followed by 35 cycles of 94 degreeC/1min, 52 degree C/1min, 72degreeC/2.5min and a final step at 72 degree C/5min. performed with 0.16 pmol each primer MO101 and ERS-1S according Yamazaki (2006), 2.4 mM MgCl2, 10X of TaqBuffer, 0.2mM of each DNTP, 2 U Taq DNA polymerase (Fermentas) 1.5 microliter of DNA and ultrapure water to 25 microliters final volume. Thermal cicling condition was 94degreeC/4min followed by 35 cycles of 94degreeC/1min, 52degreeC/1min, 72degreeC/2.5min and a final step at 72degreeC/5min.

Positive samples were submited to  E.rhusiopathiae identification according Yamazaki (2006). PCR conditions were 0.16 pmol of primers ERY-1F and ERY-2R (16), 5mM MgSO 1X buffer  4, electrophoresis in gel agarose (2%), stained by ethidium bromide and analyzed in transilluminator.

From 310 samples, 71 (22.9%) were positive to E. tonsillarum and 13 (4.19%) to E. rhusiopathiae as shown in table 1.  All municipalities had positive animals to E. tonsillarum in Mato Grosso State but only 63.63% (7/11) had positive to  E. rhusiopathiae.Prevalence studies about  E. rhusiopathiae  and  E. tonsillarum  shows great differences in many studies probably because diagnostic test used  and local areas of study. Our results based on PCR show a high prevalence of E. tonsillarum (22.9%) compared to other countries,such  Thailand countries (8.14%). In similar study realized in south and southeast Brazil it was find 4.7 to 43% of prevalence of E. rhusiopathiae but these results could have been underestimated because the low sensibility of technique employed or the immunization herd status.Herein we found a lower prevalence of  E. rhusiopathie comparing to others Brazilian regions, PCR, 0.2mM DNTP, 1U of  Taq DNA polimerase high fidelity (Platinum) in final reaction volume of 25L. Thermal cycling condition were initial step at 94degreeC/4min followed by 35 cycles of 94degreeC/1min, 58degreeC/40sec, 68degreeC/2.5min and a final step at 72degreeC/5 min.  All PCR products were separated by 19.41% of positive animal which 86.87% were  E. rhusiopathiae. This low prevalence of E. rhusiopathiae when compared to E. tonsillarum could be result from the vaccination scheme used in.

our region where just one animal was found unvaccinated to E. rhusiopathiae. E. tonsillarum was been detected widespread in swine of Mato Grosso State and was demonstrated that have a low prevalence of E. rhusiopatiae.

(table)