Wrazliwosc in vitro i in vivo Streptococcus suis na ceftiofur

The aim of the study was to determine ceftiofur sensitivity of Streptococcus suis isolated from pathologically altered brains and joints of pigs with streptococci compared with the efficacy of treating two diverse forms of Streptococci infections in pigs (neurological and joint infections) with the same antibiotic depending on the severity of the clinical signs. The study was carried out on two farms - “P” and “W”. The results of the in vitro study demonstrated that 98.5% of the 67 Streptococcus suis isolates were sensitive to ceftiofur. Only one isolate from the joint was medium sensitive. The efficacy of the treatment (in vivo studies) in stage I of both the neurological form (apathy, auricular symptoms) and articular form (lameness, lack of evident swelling or mild swelling of one joint) of streptococcal disease proved to be significantly high on the farms (between 90.3-100%). The efficacy of treating more severe cases was lower and the course treatment was also longer. The proportion of recoveries in the neurological form (increase of body temperature above 41.0°C and in coordination) of streptococcal infections ranged from 66.7% on farm “W” to 72.8% on farm “P”. The results obtained in analogous groups of animals with moderately severe joint infections (lameness and evident swelling of one joint) ranged from 47.7% on farm “W” to 56.4% on farm “P”. The proportion of the recovered animals affected with neurological symptoms of stage III (lateral position, rowing movements) was 44.4% on “P” farm and merely 28.6% on farm “W”. A positive outcome of polyarthritis treatment during the three week observation period was noted in 10.7% of the cases on farm “P” and in only one weaner (4.5%) on farm “W”. Treatment failures of the articular form of streptococcal infections compared to the neurological form were not estimated in terms of losses but rather as chronic inflammations persisting beyond the observation period and requiring further therapeutic procedures or, more frequently, culling of the animals. It may be concluded that ceftiofur is characterized by its significant efficacy in treating clinical symptoms which have been diagnosed early and cured. The in vivo studies, where there was an intensification of the disease data, indicated the antibiotic’s efficacy and good penetration into joints and cerebrospinal fluid during inflammation. Speed in diagnosing and treating an ongoing S.suis infection plays a critical role in the efficacy of the therapy.