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The purpose of this paper is to provide characteristics of the spread of African Swine Fever (ASF) in Poland from February to August, 2014. The samples from dead wild boar and domestic pigs were submitted to the National Veterinary Research Institute, National Reference Laboratory for ASF in Pulawy, Poland, for testing by PCR and ELISA methods. In the studied period, fourteen cases of ASF in wild boar and two outbreaks in backyard pigs were confirmed. In addition to the results of laboratory tests performed in 2014, the article describes the ASF surveillance programme in wild boar and pigs in Poland carried out in 2011-2013. The spread of ASF in Poland is compared with the epidemiological situation in Lithuania, Latvia, Belarus and the Russian Federation.

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The comparison of names of the species before the reclassification of the family Chlamydiaceae into two genera with the species names acknowledged at present is presented. The pathogenicity of these species for animals and man is characterised.

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Enterotoxigenic Escherichia coli (ETEC) may produce heat-labile (LT) and heat-stable (STI or STII) enterotoxins. Differentiation between ETEC and other pathogenic and non-pathogenic E. coli as well as other Gram-negative bacteria responsible for induction of diarrhoea, requires isolation, biochemical identification and determination of toxins (or their genes--elt, estI, estII). A multiplex polymerase chain reaction (PCR) system for the rapid and specific detection of enterotoxin-gene-positive E. coli was developed. The primers described by other authors, specific for the universal stress protein A (UspA) of E. coli and enterotoxin genes were used and allowed a simultaneous amplification of the E. coli-specific uspA and the respective toxin genes. The specificity of this multiplex PCR system was confirmed by testing ETEC, non-ETEC and other non-E. coli bacteria. The specific 884 bp uspA gene and 280 bp (eltI), 166 bp (estI) or 278 bp (estII) amplification products were generated with the respective ETEC strains whereas no amplification was detected with non-E. coli bacteria. The multiplex PCR developed allowed the rapid and specific identification of enterotoxin-producing E. coli colonies directly grown from faecal samples of pigs with diarrhoea. The test may be used as a method for the determination of ETEC among other pathogenic groups of E. coli and other Gram-negative enteric isolates.

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E. coli strains isolated from pigs with postweaning diarrhea or edema disease were tested by phenotypic and genotypic methods for the presence of virulence antigens and genes, respectively. The slide agglutination and ELISA analyses were used for determination of F4, F5, F6, F17, and F41 fimbriae whereas the prevalence of fimbrial fedA and toxin eltI, estI, estII, stx1, stx2 and stx2e genes were recorded by the means of PCR. Only F4 antigen (ac variant) was found in strains of the serogroup O149:K91 isolated from pigs with diarrhea. PCR analyses showed that the fedA gene encoding F18 fimbriae was present in 61.9% of strains isolated from pigs with diarrhea and in 84.2% of strains isolated from pigs with edema disease. The eltI genes encoding heat-labile toxin I (LTI) were present only in 9 out of 21 strains recovered from pigs with diarrhea. Shiga toxin 2 variant (stx2e) genes were found in six isolates from edema disease and also in one strain from diarrhea. The PCR test used in the study was a sensitive and valuable method for determination of virulence factors of E. coli strains.

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Hare brucellosis is caused primarily by Brucella suis biovar 2. Hares along with wild boars are the natural reservoir of this microorganism. In view of restriction of applicability of traditional serological methods the work aimed to develop the ELISA to examine hare sera for the presence of anti-Brucella antibodies. Lipopolysaccharide (LPS) antigen obtained from the strain S19 of Brucella abortus and the conjugate of antibodies against rabbit immunoglobulin with horseradish peroxidase were used in the test. Hares' sera positive and negative in the CFT were used as controls of the ELISA. The sera collected from 9 hares suspected to be infected with Brucella organisms, positive in CFT (in this number 7 hares revealed clinical symptoms or anathomopathological lesions characteristic of brucellosis), 6 sera from hares showing no symptoms of the disease, negative in CFT and 520 sera from hares monitored for brucellosis were tested. All serum samples from hares suspected for Brucella infection were positive in ELISA and 2 of them were negative in RBPT. Additionally among the samples from hares monitored 12 sera were positive in ELISA and CFT, whereas 9 sera from 12 ones were also positive in the RBPT. The obtained results indicated that the ELISA developed in our laboratory proved to be equivalent in specificity to CFT. In addition, ELISA proved to be more sensitive than RBPT for the diagnosis of Brucella infection in hares.

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Veterinary laboratories which deal with infectious diseases form three groups according to the tasks for which they are responsible. The first group includes central or national veterinary laboratories, national or international reference laboratories, high-security laboratories, district regional or state veterinary diagnostic laboratories. The major role of these laboratories is to assist national Veterinary Services in diagnosing infectious animal diseases. The second group comprises laboratories that produce veterinary diagnostic kits and those that produce veterinary vaccines. The third group is composed of veterinary research laboratories, which generally concentrate on basic research and do not contribute directly to the diagnosis and control of infectious animal diseases. The author describes the objectives of each of the three groups of laboratories.

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The American Board of Family Practice is developing a computer-based recertification process to generate patient simulations from a knowledge base. Simulated patients require a stochastically generated history and response to treatment, suggesting a Monte Carlo-like patient generation process. Knowledge acquisition experiments revealed that description of a patient's overall health as a node in a Monte Carlo model was difficult for domain experts to use, severely limited knowledge reusability, and created a plethora of awkwardly defined health states. We explored a model in which patients traverse several parallel health state networks simultaneously, so that overall health is a vector describing the current nodes from every Parallel Network. This model has a reasonable biological basis, more easily defined data, and greatly improved reuse potential, at the cost of more complex simulation algorithms. Experiments using osteoarthritis stages, weight classification, and absence or presence of gastric ulcers as three Parallel Networks demonstrate the feasibility of this approach to simulating patients.

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The number of Salmonella typhimurium per gram of caecal contents of chicks, given orally prior to infection with different preparations containing protective intestinal flora, was significantly lower than in the control group. The best results were obtained when the lyophilised caecal rinses were given orally to 1-day-old chicks. Less effective methods of protection of the alimentary tract proved to be oral application to chicks of fresh faeces or lyophilised faeces and administration of the lyophilised caecal rinses with drinking water. Oral application of undefined anaerobic caecal culture to chicks proved to be the least effective of the methods investigated of protecting them against Salmonella colonisation, although even these results differed statistically from those of the controls. The percentage of infected birds 7 days after challenge confirmed the efficacy of oral application of lyophilised caecal rinses--only 30% of individuals from the group treated in this way proved to be Salmonella positive. In contrast, the percentage of infected birds in other experimental groups ranged from 50% to 75% and was 100% in the controls.

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BACKGROUND: The American Board of Family Practice is developing a computer-based recertification process. An optimal implementation requires a formal model of family medicine, which will become the basis for a knowledge base. DESIGN: The proposed model of family medicine contains six entities: Population, Record, Agents of Change, Health States, Findings, and Courses of Action. The model illustrates 15 important relations between entities. For instance: Health States Lead to Health States, and Findings Associate with Health States. These two relations describe natural history, manifestations of disease, and the effects of medical interventions and risk factors. Because time is such an important aspect of primary care, nearly all numeric data are represented as graphs of possible values over time, called Patterns, which include details about periodicity. Patterns and other aspects of the model provide a means of describing covariance between observations, such as the influence of height on weight. RESULTS: The model reflects many family practice activities and suggests some formal descriptions of family practice. For instance, diagnostic activities focus largely on classifying early or short segments of Patterns in Findings. Most medical interventions attempt to alter either the probability distributions in a Lead-to relation or the impact of a Finding. CONCLUSION: The proposed model of family medicine could find uses in many applications, including computer-based tests, medical records, reference systems, and decision support tools.

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The authors discuss the role played by international and regional organisations in the registration and testing of veterinary biological products. International organisations which contribute significantly to this field include the Office International des Epizooties (OIE)--through the work of the Standards Commission and the publication of the Manual of standards for diagnostic tests and vaccines--, the Food and Agriculture Organisation of the United Nations (FAO) and the World Health Organisation (WHO)--through the work of the Joint FAO/International Atomic Energy Agency (IAEA) Division of Nuclear Techniques in Food and Agriculture in standardising enzyme-linked immunosorbent assay (ELISA) techniques, as well as through WHO Expert Committees. In Europe, the most important regional organisations are the European Commission and the European Pharmacopoeia. In the Americas, the most significant contribution is made by the two specialised institutes of the Pan American Health Organisation (namely INPPAZ [Pan American Institute for Food Protection and Zoonoses] and PANAFTOSA [Pan American Foot and Mouth Disease Centre]), and by the Inter-American Institute for Cooperation in Agriculture. In Africa, PANVAC (the Pan-African Veterinary Vaccine Centre) continues to perform valuable work in testing veterinary vaccines. For the industrialised countries, the Organisation for Economic Co-operation and Development (OECD) is involved in the regulation of biotechnology products and in standardising "good laboratory practice' for vaccine manufacture. A table is presented which summarises and compares the respective roles of these organisations in the harmonization of licensing and testing procedures, the distribution of reference reagents, vaccine testing and the creation of vaccine banks.

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The purpose of this paper was (1) comparison of four multi-step methods used for Salmonella isolation from meat- and bone powder; (2) elaboration of a new sensitive method of Salmonella isolation from this product; (3) evaluation of a new solid selective medium (BxLH) described by the authors for Salmonella isolation in comparison to brilliant green agar (BGE) according to Edel and Kampelmacher. The study was carried out on 173 meat- and bone powder samples naturally contaminated with Salmonella oranienburg. The samples were examined for the Salmonella presence by means of four compared methods (Methods 1 to 4). The new method of isolation proposed by the authors (Method 3) proved to be the most effective among all compared for Salmonella recovery. It seems that the superiority of Method 3 in comparison to the other applied was a result of, (1) homogenization of the investigated samples in distilled water before preincubation followed by maintenance at room temperature for 2-4 h; (2) the use of a new selective BxLH agar; (3) the use of multiple plating after selective enrichment. The BxLH medium was shown to be more suitable for Salmonella isolation than BGE agar because of more efficient inhibition of other bacterial growth with simultaneously abundant growth of the Salmonella organisms. The additional advantage offered by BxLH agar was the fact that lactose-positive salmonellas grow as typical representatives of this genus. This enables their identification, in contrast to the situation when lactose containing media are used, where the colonies of such salmonellas are similar to the colonies of, for example, Escherichia coli.

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The mucosal immune system is a very important component of the body's defence against pathogenic organisms, especially those responsible for enteric infections. On the basis of the concept of a common mucosal immune system, there is currently much interest in the possibility of developing oral vaccines against respiratory and urogenital tracts infections. There is also a great need to develop strategies for enhancing delivery of antigens to the mucosal immune system as well as to identify mucosa-active immunostimulating adjuvants.

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The aim of the study was to evaluate, under large-scale farm conditions, the prophylactic effect of various inactivated E. coli vaccines in the control of pig colibacillosis. The investigations were carried out with 2472 pregnant sows, immunized with 8 different vaccines containing E. coli fimbrial adhesins and adjuvants. Efficacy of the biologicals used was tested by evaluation of the health state of the newborn piglets, i.e. number of born and weaned piglets, percentage of piglets with diarrhea and dead piglets, and mean body weight gain of weaned piglets. It was also intended to check the influence of immunization on the number of pathogenic E. coli strains in the faeces of piglets originating from the vaccinated sows. The vaccines used in the study differed in their protective effect but all of them had a positive influence on the health status of the newborn piglets as well as on the reduction in the faeces of the number of pathogenic E. coli isolates. The best results were obtained when pregnant sows were immunized with a vaccine containing purified K88, K99, and 987P fimbriae and B subunit of LT enterotoxin. It seems that the determination of the number of pathogenic E. coli strains in the faeces of piglets originated from dams vaccinated against colibacillosis can be helpful in the evaluation of the vaccine efficacy.

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Between 1990 and 1992, serum samples from 55,478 domestic swine were tested by enzyme-linked immunosorbent assay (ELISA) for the presence of hog cholera virus (HCV) antibodies. The amount of antibody in the sera was expressed as the mean percentage inhibition (PI). For diagnosis, the tested sera were diluted 1:2 and considered positive if the PI was less than 25%. Sera giving PI values in the range of 25-50% were retested against HCV and bovine virus diarrhoea virus (BVDV), by neutralising peroxidase-linked assay. Comparison of the serum titres obtained was used for serological diagnosis of hog cholera; the tested sera were considered negative for hog cholera if the titre for BVDV was higher than that obtained for HCV. All sera with a PI higher than 50% were considered negative for HCV and BVDV. All sera were found to be free of antibodies to HCV. BVDV antibodies were demonstrated in 0.40% of the sera tested in 1990, in 1.80% in 1991 and 1.06% in 1992.

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1125 and 1146 E. coli strains isolated from suckling and weaned piglets with diarrhea, respectively, and 724 strains from healthy piglets were tested for the presence of fimbriae and production of enterotoxins. The fimbriae were determined by hemagglutination and slide agglutination tests, enterotoxins--by the use of ileal loop test in piglets (LT and STb enterotoxins) and suckling mouse assay (STa enterotoxin). It was found that 72.8 and 53.0% strains, isolated from diseased suckling and weaned piglets, respectively, possessed specific fimbrial hemagglutinins, in most cases with K88 antigen. Additionally, 987P fimbriae were detected in 14.0 and 0.7% strains isolated from piglets with diarrhea. Only 5 strains (0.7%) recovered from healthy piglets had specific fimbriae, usually with undetermined antigenic structure. F1 fimbriae (called common or unspecific) were found in strains isolated both from diseased (15.2 and 16.3% strains, respectively) and healthy piglets (27.1% strains). It was noted that the strains isolated from suckling and weaned piglets with diarrhea in most cases were enterotoxigenic (90.5 and 69.1% strains, respectively) and most frequently produced heat-labile toxin LT alone or with STb. 18.5% of enterotoxigenic strains isolated from healthy piglets produced STa toxin.

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The Office International des Epizooties (OIE) is the World Animal Health Organisation created in 1924 in Paris. The following activities have been started in order to promote standardisation of biologicals: a) preparation of the OIE Manual of Standards for Diagnostic Tests and Vaccines; b) organisation of Reference Laboratories for diseases of Lists A and B; c) establishment, in cooperation with WHO, FAO and IAEA, of international standards for diagnostic tests with particular reference to the ELISA. The Manual will be distributed worldwide in 1992 and 1993 and this will contribute to an internationally unified approach to diagnosis and immunoprophylaxis, in other words to international harmonisation of veterinary biologicals. It is planned that future OIE Reference Laboratories, now being organised, will supply the necessary standards.

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The paper presents the possibilities, difficulties and inabilities of veterinary medicine in the prophylaxis of zoonotic diseases in humans. With reference to this, the author characterized Salmonella paratyphi induced alimentary toxicon-infections, Q fever and chlamydiosis. The article also discusses current views on some neoplastic diseases in animals and their possible transmission to humans.

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The purpose of this work was to define more precisely the role of Ureaplasma organisms in the aetiology of granular vulvovaginitis and balanoposthitis (GVVBP) of cattle. To contribute to this question the frequency and degree of infection with Ureaplasmas in two main groups of cattle was taken into account: (a) in cattle with symptoms of the mentioned disease, (b) in cattle without clinical symptoms. The samples of semen from 301 sires with symptoms of GVVBP and from 43 healthy sires as also vaginal mucus swabs from 96 cows with GVVBP and from 40 cows mated by the sire infected with Ureaplasma organisms and from 50 cows inseminated with semen which contained Ureaplasma organisms were taken for bacteriological examinations. The control group in relation to the above mentioned cows constituted of 22 heifers free from symptoms of GVVBP and neither inseminated nor mated naturally. It has been shown that on an average 78.1% of sires with pathological changes in the mucosa of the penis or prepuce and only 25.6% of healthy sires were infected with Ureaplasma organisms. The concentration of Ureaplasma organisms was also significantly higher in material obtained from sires with symptoms of the disease than in that from healthy animals. Ureaplasma organisms were demonstrated more frequently (72.7%) in cows with GVVBP than in cows without these symptoms (13.3%). Similarly, as in the material obtained from sires, in the material taken from cows with symptoms of the disease the concentration of Ureaplasma organisms was significantly higher than that in the material originating from the healthy cows. The obtained findings may indicate that Ureaplasma organisms play a role in the aetiology of GVVBP.

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Three-hundred and fifty-eight E. coli strains isolated from piglets were tested for the presence of hemagglutinins by the use of the active hemagglutination test with or without mannose. Additionally 86 strains from the mentioned number of strains were investigated for the presence of common fimbriae using the same method but growing the strains in media especially suited for the development of this kind of fimbriae. These 358 strains and additionally 202 E. coli strains were tested using antisera for 987P and K88 antigens. It was found, using the active hemagglutination test, that 51.4% of the strains were hemagglutinating. The hemagglutinating strains carried the K88 antigen. All these strains were isolated from new-born and weaned piglets with enterotoxic form of colibacillosis, called also E. coli diarrhea. From cases of this form of colibacillosis originated also 26.7% of the strains in which common fimbriae (type 1) were detected. This result was obtained when the BHI medium was used for cultivation. In case of TSA medium only 2.3% of strains were positive. No specific or common fimbriae were found in strains recovered from septic form of colibacillosis and oedema disease (called also enterotoxaemic form of colibacillosis). No strain of 560 examined showed the presence of fimbrial 987P antigen.

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