Porcine Kobuvirus (PKV) infection is very common in pigs throughout the world. Since it has never been investigated in Serbia, to contribute to the knowledge of Porcine Kobuvirus , its role, and distribution, we tested 200 samples from domestic pigs and wild boars. From domestic pigs, 10 fecal, 22 spleen and 68 serum samples, and 100 spleen samples from wild boars were tested. The virus prevalence determined by real-time RT-PCR in domestic pigs was 22% and in wild boars 6%. The phylogenetic analysis of 3D region revealed that Serbian strains are closest related to the Hungarian strain from wild boar from 2011. This is the first report on PKV in Serbia in domestic pigs and wild boars, implying its wide circulation. Although the infection could not be directly related to any clinical manifestation, the frequency of virus found in feces suggests viral affinity to the gastrointestinal tract. However, due to the rather ubiquitous presence of PKV, the clinical and pathological assessment have to be considered when PKV infection is diagnosed.

At a commercial farrow-to-feeder pig system with 2,100 sows in Serbia, lesions resembling porcine ear necrosis syndrome were observed in 80% of the weaned pigs at 45–50 days of age. Pathomorphological examinations were carried out on 10 pigs that had been found dead. The gross lesions ranged from mild, superficial dermatitis to severe, deep inflammation with exudation, ulceration and necrosis. Histopathological examination revealed erosive and ulcerative dermatitis of the pinna with neutrophilic and lymphocytic infiltration and bacterial colonies in the crusts. Staphylococcus aureus (MRSA strain), Staphylococcus hyicus and Streptococcus group C were cultivated from eight, S. hyicus from two ear tissue scraping samples. All 10 samples were positive for treponemes and phylogenetic analysis of two polymerase chain reaction products confirmed the relationship to Treponema (T.) medium/vincentii and Treponema pedis. Treponemes were also detected in seven oral swabs that were analysed to obtain evidence of the transmission of this bacterium by ear biting. The contribution of non-infectious factors to this misbehaviour could not be ruled out as the crude protein concentration of the feed was inappropriate and the climate of the pig house was suboptimal. The concentrations of selected mycotoxins in the feed were not elevated. However, the contribution of both infectious and non-infectious factors to the onset of disease was most probable.

Methicillin-resistant Staphylococcus aureus is a highly important human pathogen that is also a significant concern in veterinary medicine. Despite the high prevalence of colonization, clinical infections with methicillin-resistant Staphylococcus aureus appear to be rare in pigs. Methicillin-resistant Staphylococcus aureus was isolated from a sow with endometritis and her five piglets with dermatitis originating from a Serbian farm. Identification of the strains was done by automated system and confirmed by polymerase chain reaction for mecA and nuc genes. Detection of Staphylococcal Cassette Chromosome mec type was performed by multiplex polymerase chain reaction. Antimicrobial susceptibility testing on erythromycin, clindamycin, gentamicin, kanamycin, tobramycin, ciprofloxacin, tetracycline, trimethoprim/sulfamethoxazole and vancomycin was done by disc diffusion method. Six isolated strains from the infected sow and her piglets showed resistance only to tetracycline beside resistance to all beta-lactam antibiotics. In the tested methicillin-resistant Staphylococcus aureus isolates, Staphylococcal Cassette Chromosome mec type V was present. To our knowledge, this finding is the first documented detection of methicillin-resistant Staphylococcus aureus from pigs' clinical samples in Serbia. The results of our study indicate the emergence of methicillin-resistant Staphylococcus aureus in a pig farm in Serbia highlighting the threat of this antibiotic-resistant microorganism as a pathogen causing both animal and human infections.

Vaccines are a very effective tool for the prevention and eradication of infective diseases in both veterinary and human medicine. Although for safety reasons, vaccines undergo very strict controls before being placed on the market, the risk of adverse reactions is not eliminated. According to the World Health Organization (WHO), adverse event following immunization (AEFI) is any untoward medical occurrence that follows immunization and which does not necessarily have a causal relationship with the usage of the vaccine. Adverse reactions may arise as a direct consequence of immunization due to the specificity of the vaccine itself, the quality of the vaccine or the immunization errors. In addition, adverse reactions may also be the result of a coincidental relationship between the effect and immunization. However, biological mechanisms of AEFI are very complex. During the mass vaccination campaigns, when a large number of animals are vaccinated in a short period of time, adverse reactions are expected to be the most frequently reported. In Serbia, livestock is currently being vaccinated against Lumpy Skin Disease, Bluetongue, and Classical swine fever.

Among different pathogens, enterotoxic E. coli (ETEC) has been for many years an important etiological agent in the occurrence of digestive system disease of newborn animals. In counties with developed pig breeding (farming), including our country, diarrhea in the neonatal period, caused by ETEC strains is one of the most present and economically most significant diseases. The aim of this investigation wais to determine the prevalence of ETEC strains in piglets (weaning pigs), originated from 5 (five) pig farms in the Republic of Serbia, as well as their serological typization based on characteristics of somatic O antigens, presence of fimbrial antigensadhesins and hemolytic activity. The material for this investigation was targeted and sampled from piglets that have shown clinical signs of neonatal diarrhea or pathoanatomical changes characteristic for enteritis caused by ETEC strains. The total number of isolated ETEC strains were 148, of which 91 (61.48 %) were determined on the basis of somatic O antigen characteristics. The largest number of strains, 42 (46.15 %) belonged to serotype O149. Serological types O8 and O147 were represented, each with 15 strains (16.48 %). In 13 (14.28 %) strains the somatic antigen which belonged to serotype O138 was determined and in 6 (6.59 %) strains the antigen belonged to serotype O157. No strain agglutinated with hyperimmune O139 serotype serum. The presence of fimbrial adhesins was determined in 47 (51.64%) strains and of that number the F4 type of fimbrial adhesins was detected in 38 (80.85 %) strains. The presence of F5 adhesins was determined in 4, and F6 in 3. In 2 strains, the paralell presence of two adhesin types, F4 and F6 was detected. The greatest number of strains 30 (71.42 %) with adhesin F4 belonged to O149 serotype, a considerably smaller number, 4 (26.66%) to serotype O8, 2 strains to serotype O157 and to each serotype O147 and O138 1 strain. The fimbrial adhesin of F5 type was detected in 3 strains which belonged to serotype O8 and in 1 strain of serotype O149. All 3 strains with F6 adhesin, belonged to serotype O8. From 2 strains which had, at the same time, adhesins F4 and F6 one belonged to serotype O8 and the other to serotype O138. Hemolytic activity was present in 42 (46.15 %) strains, of which 34 strains belonged to O149 serotype, 6 strains to O157 serotype and 2 strains to O147 serotype