Detection of Mycobacterium avium subspecies paratuberculosis of dairy cows in Bogor

Johne’s disease (JD) or partuberculosis is a chronic granulomatous enteritis in ruminants caused by infection of Mycobacterium avium paratuberculosis subspecies (MAP). The disease has been detected serologically in Indonesia. It’s potential to spread to other herds and could create great economic losses. The objectives of current study were to detect MAP in milk and faeces of dairy cows as well as to evaluate the association between farm management factors and presence of the bacteria in dairy cows in Bogor. The sample size was calculated using the formula to detect disease with the prevalence assumed to be 5% using 95% significant level. Milk and faeces samples were taken from 62 dairy cows which were suspected as suffering from MAP infection. Detection of MAP was done by isolation in Herrold’ egg yolk medium with mycobactin J (HEYMj), acid-fast bacilli Ziehl-Neelsen staining, PCR IS900 and F57. Biochemical test to confirm M. tuberculosis presence was also conducted. Fifteen isolates of Mycobacterium sp. were found from the faeces samples but not from the corresponding milk samples. However, conventional PCR conducted on the isolate as well as the milk samples, gave negative results. Biochemical test proved that all Mycobacterium sp. isolates were not M. tuberculosis. This study indicated the prevalence of MAP in Bogor was less than 5%. These findings should be continued by observational study to achieve the comprehensive information at the cattle and herd level. Bovine Tuberculosis monitoring should be done also to protect dairy herd and food safety for the community. Key words: Johne’s disease, Mycobacterium avium subspecies paratuberculosis, Milk, Faece

Status Quo der Vermarktung ökologischer Ziegenmilchprodukte: Sicherung von mikrobiologischer Qualität und Authentizität am Modell der Region Hessen

Für eine Status-Quo-Erhebung am Modell der Region Hessen wurden ökologisch bzw. zu Vergleichszwecken konventionell erzeugte Ziegenmilchprodukte (Ziegenkäse) aus Direktvermarktung und Handel auf mikrobiologische Qualität und tierartspezifische Authentizität untersucht. Die mikrobiologischen Untersuchungen von 183 Proben zeigen, dass Ziegenkäse aus regionaler Direktvermarktung in Hessen hinsichtlich Gesundheitsrisiken durch pathogene Keime kein über dem für vergleichbare Produkte liegendes Problem darstellt. Für Ziegenkäse aus einigen Betrieben wurden aber deutliche Hygienemängel festgestellt, in Produkten zweier Betriebe (davon ein ökologisch wirtschaftender Direktvermarkter) mit den stärksten Hygienemängeln wurden zudem Listeria monocytogenes nachgewiesen. Die molekularbiologische Untersuchung von 160 als reine Ziegenmilchprodukte deklarierten Proben mittels PCR ergab, dass - mit Ausnahme der Produkte eines auffälligen Betriebes - ökologischen Produkte aus regionaler Direktvermarktung keine Kuhmilchzusätze enthielten. Bei Importprodukten war der Anteil positiver Proben je nach Ursprungsland sehr unterschiedlich. Insgesamt ergab sich für die untersuchten Parameter somit ein überwiegend positives Gesamtbild, die Produkte einzelner Betriebe mussten jedoch als problematisch angesehen werden. Aufgrund der Befunde erscheint es sinnvoll, zur Sicherstellung einer durchgehend guten Qualität und der gesundheitlichen Unbedenklichkeit in einigen Bereichen, insbesondere im Hinblick auf mikrobiologische Hygienemarker, verstärkt Routineuntersuchungen durchzuführen

Paralytic shellfish poisoning (PSP) toxin binders for optical biosensor technology: problems and possibilities for the future: a review

This review examines the developments in optical biosensor technology, which uses the phenomenon of surface plasmon resonance, for the detection of paralytic shellfish poisoning (PSP) toxins. Optical biosensor technology measures the competitive biomolecular interaction of a specific biological recognition element or binder with a target toxin immobilised onto a sensor chip surface against toxin in a sample. Different binders such as receptors and antibodies previously employed in functional and immunological assays have been assessed. Highlighted are the difficulties in detecting this range of low molecular weight toxins, with analogues differing at four chemical substitution sites, using a single binder. The complications that arise with the toxicity factors of each toxin relative to the parent compound, saxitoxin, for the measurement of total toxicity relative to the mouse bioassay are also considered. For antibodies, the cross-reactivity profile does not always correlate to toxic potency, but rather to the toxin structure to which it was produced. Restrictions and availability of the toxins makes alternative chemical strategies for the synthesis of protein conjugate derivatives for antibody production a difficult task. However, when two antibodies with different cross-reactivity profiles are employed, with a toxin chip surface generic to both antibodies, it was demonstrated that the cross-reactivity profile of each could be combined into a single-assay format. Difficulties with receptors for optical biosensor analysis of low molecular weight compounds are discussed, as are the potential of alternative non-antibody-based binders for future assay development in this area