[Comparative studies on detection of Chlamydophila psittaci and Chlamydophila abortus in meat turkey flocks using cell culture, ELISA, and PCR]. / Vergleichende Untersuchungen zum Nachweis von Chlamydophila psittaci und Chlamydophila abortus in Putenmastbetrieben mittels Zelikultur, ELISA und PCR.

The prevalence of chlamydia in 10 meat turkey flocks was investigated. As samples served of each moment of collection and sex of the animals 10 cloacal swabs which were taken at the age of 1, 4, 8 and 12 (females) or 16 weeks (males) and at the time of slaughter at the age of 16 or 20 weeks. Spleen samples were taken at the time of slaughter, additionally. These were pooled making 1 pool out of 5 individual samples. The cloacal and spleen pools were examined by nested PCR (nPCR), Capture-ELISA and Capture Blocking-ELISA directly as well as after isolation attempts in cell cultures. The most sensitive method to detect chlamydia, with 6 isolates proved to be the isolation by cell culture followed by detection using nPCR. Not corresponding to the results of the nPCR were 4 positive reactions found by the Capture-ELISA which could in no case be affirmed by Capture-Blocking-ELISA. The direct examination of cloacal swab pools by nPCR proved positive in only 2 cases. In contrast to this the examination of these samples by Capture-ELISA showed a high percentage of 71.9% positive results, of which only 2 cases were confirmed by nPCR and none by Capture-Blocking-ELISA. Of the 8 Chlamydia positive results in the nPCR 7 could be classified by DNA sequencing to Cp. abortus and only one to Cp. psittaci.

Effect of sample selection from experimentally contaminated hatching eggs and freshly hatched chicks on Salmonella enteritidis detection rate.

The conventional culture methods of hatching eggs using shell and/or egg contents for detection of salmonella organisms give mostly unsatisfactory results. The aim of the present study is to evaluate selection of other samples and techniques of culturing hatching eggs and freshly hatched chicks. This current study provides the best evidence of Salmonella enteritidis in artificially contaminated eggs (Layer type) by using enrichment broth in empty egg shell samples in comparison to culturing samples from yolk, albumen or from shell above the air cell (with the outer shell membrane). The isolation rates could be enhanced if empty egg shell was initially filled with Buffered Pepton Water as pre-enrichment broth. Examination of organs from freshly hatched chicks revealed that crop samples give mostly higher reisolation rates.