Mycobactin J-dependent mycobacterial isolates from sheep, goat, and cattle herds with Johne's disease in Morocco, South Africa, the United States, and Germany were tested for the repetitive insertion sequence IS900 of Mycobacterium paratuberculosis by PCR. The IS900 PCR target sequence was detected in 90 of 93 fecal culture isolates tested (96.8%). Restriction fragment length polymorphisms (RFLPs) and in vitro growth characteristics were studied in 46 of the IS900-positive isolates and in two bovine vaccine strains of M. paratuberculosis. Five different RFLP types were identified in PvuII digests of genomic DNA by Southern hybridization with a DNA probe specific for IS900. All isolates of M. paratuberculosis could be classified into two major clusters by their growth rates as well as the relatedness of their PvuII-RFLP hybridization patterns. All of the sheep isolates were classified into cluster I (extremely slow growth), while all cattle and goat isolates were members of cluster II (moderately slow growth). Different PvuII-RFLP patterns were detected in different sheep flocks from Morocco and South Africa. Our results demonstrate that genetically and phenotypically different strains of M. paratuberculosis were present in ruminant populations. The strains from sheep in Morocco and South Africa tested in the study appeared to belong to a unique group of M. paratuberculosis strains that might have adapted to this host species. The presence of several genetically distinct strains in different sheep flocks suggested that analysis of IS900-specific RFLP patterns may provide a useful tool for the epidemiologic investigation of ovine paratuberculosis outbreaks. MATERIALS AND METHODSBacterial strains and growth conditions. A total of 93 mycobacterial field isolates was examined in the study. All of the strains had been cultured from fecal samples by standard procedures and were maintained aerobically at 37ЊC on Loewenstein-Jensen solid medium supplemented with mycobactin J (Rhone Merieux, Laupheim, Germany). Isolates were presumptively identified as M. paratuberculosis on the basis of slow growth, mycobactin J dependency, acid fastness (by Ziehl-Neelsen staining), and colony morphology (8). The strains obtained in Morocco were isolated during a survey of three farms located 85 km north (farms M1 and M2) and 15 km south (farm M3) of the city of Rabat. A frequent exchange of some animals between farms M1 and M2 was reported. On farm M1, 17 presumptive M. paratuberculosis strains were isolated from 51 sheep by fecal culture methods, 23 strains were isolated from 80 sheep on farm M2, and 14 strains were isolated from 49 sheep on farm M3. On farm M1, one strain was also occasionally isolated from a cow. All animals tested were suspected of suffering from paratuberculosis because they exhibited slow, progressive weight loss and in some cases had diarrhea nonresponsive to anthelmintic or antibiotic treatment. Isolation of M. paratuberculosis strains from sheep on farm M1 and corresponding clinical and histopathological finding...
1,268 sera collected from slaughtered pigs in Hassia (FRG) from 1986 to 1988 were tested for antibodies against porcine and human influenza A V~N S strains using the single radial haemolysis test Antibodies against the porcine strains (subtype HlN1) A/Swine/Arnsberg/l/81, A/Swine/ Iowa/15/30 and A/New Jersey/7/76 were detected in 411 (32.4 %), 318 (25.1 %) and 304 (24.0%) of sera, respectively. Up to 1988 a slight increase (10 %) in the seroprevalence to A/Swine/Arnsberg/l/Sl was noticed, whereas the results obtained with the other strains showed little variation.Antibodies against the human H l N l strain A/Singapore/6/86 were only found in sera collected 1987 and 1988 in rates of 1.6% and 3.0%. Serological indication of infections with the human H3N2 strains ANictoridll75, A/Hong Kong/1/68 and A/Philippines/2/82 could be shown in 286 (22.6 YO), 178 (14.4%) and 135 (10.6%) of the serum samples. Within the three year period the rate of sera positive for antibodies against A/Philippines/2/82 increased from 6.5 % to 23.0 %, whereas no variation in the rates were found using the other H3N2 strains.Antibodies simultaneously against porcine ( H l N l ) and human (H3N2) virus strains were detected in 9.9% of all sera tested.
Summary In an attempt to estimate the importance of Johne's disease in sheep in Morocco, a diagnostic survey was made in three flocks suspected of being infected with Mycobacterium paratuberculosis. Blood and faeces samples collected randomly from 188 adult sheep were investigated using direct microscopy of fecal smears, fecal culture and the serum complement fixation test (CFT). Microscopical examination of faeces revealed acid‐fast bacteria in 67 (35.6 %) samples. However, Ziehl‐Neelsen staining lacks specificity and furthermore, acid‐fast bacteria could only be demonstrated in 34 (60 %) animals found to be culturally positive. Fecal culture succeeded in the isolation of mycobactin dependent strains of M. paratuberculosis in 56 (29.8 %) of the sheep examined, with three strains growing in yellow‐pigmented colonies. The CFT was regarded as positive (titres of 1:10 and higher) in 55 (29.2 %) sera of animals, demonstrating a sensitivity of 48.2 % and a specificity of 74.5 % in relation to fecal culture. From the results, it can be concluded that the combination of CFT and fecal culture might be a practical and useful procedure for detecting infected sheep within flocks and for controlling Johne's disease. This study supports the suspicion that paratuberculosis may constitute a serious problem in Morocco, particularly in sheep flocks involved in cross‐breeding programmes.
in Swine Sera by the Single Radial Haemolysis (SRH)and the Haemagglutination Inhibition (HI)-Test 224 sera collected from slaughtered pigs in Hassia (FRG) were tested for antibodies against 4 influenza-A-virus strains (subtypes H l N l and H3N2) of human and swine origin using the single radial haemolysis technique (SRH) and the haemagglutination inhibition test (HI). With both methods corresponding positive and negative results were gained in ca. 90% of the sera tested. However, the SRH resulted in about 5 YO more positive reactions than the HI. Divergent results were observed mainly in sera with low antibody levels.The SRH, which is less affected by nonspecific inhibitors and isoagglutinines, seems to be superior to the H I and suitable for screening large numbers of serum samples. The results also offer first informations of the distribution of influenza-A-virus infections in pigs in the country of Hassia.
Summary Paratuberculosis (Johne's disease) was suspected in a flock of approximately 1000 sheep after weight losses and scouring had increased in adult animals despite repeated anthelmintic treatment. A total of 10 ewes showing clinical symptoms were submitted to laboratory examination. Gross pathological and histological examination of tissue samples rendered results compatible with Johne's disease in all 10 ewes. The diagnosis could only be confirmed by cultural isolation and identification of Mycobacterium paratuberculosis in the faeces of two ewes. This is considered the first documented isolation of Mycobacterium paratuberculosis in sheep in Morocco.
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