On the Importance of Bacterial L‐Forms in Pigeons*

Abstract

Summary Following a definition of bacterial L‐forms and a literature review on introduction and reversion of bacteria to and from L‐forms, respectively, the results of a study comprising 587 samples (316 pigeons and 271 pigeon eggs) are reported. As a control 25 free living pigeons and 25 eggs of those pigeons were used, because antibiotic treatment of these could be excluded. From 79 samples (75 pigeons and 4 eggs) Salmonella typhimurium var. copenhagen (STMC) was isolated (non from the urban pigeons), of them 11 in the L‐form from joints and organs and 3 from eggs. 325 of other bacterial isolates were found as L‐forms (=approx. 40%). Out of 168 serum samples investigated, 33.9% showed antibodies against STMC. Corresponding antibodies could only be demonstrated in 73.4 % of the pigeons with a STMC isolate. The occurrence of L‐forms explains resistance to therapy and the failure of vaccines. The high frequency of L‐forms is probably an indication of an inconsequential use of antibiotics in managing pigeon diseases.

Linkage of avian and reproductive tract tropism with sequence divergence adjacent to the 5S ribosomal subunitrrfHofSalmonella enterica

“…For example, S . Typhimurium 5, which is historically associated with pigeons (Kiessling et al , 1990), clustered with the avian‐restricted serotypes S . Pullorum and S .…”

“…Phylogenetic analysis of the two ISRs adjacent to 5S rrfH rRNA gene of S. enterica indicates that sequencing of a single genomic region of less than 500 bp provides a useful approach for clinicians to gain information about the serotype of any one strain of S. enterica, with the additional benefit that it resolves questions about how to classify some atypical serotypes. For example, S. Typhimurium 5, which is historically associated with pigeons (Kiessling et al, 1990), Enteritidis that contaminates eggs. The genetic linkage of these serotypes may be with reproductive tract tropism in general, because S. Choleraesuis also clustered with this group.…”

Isolation of Cilia-Associated Respiratory (CAR) Bacillus from Pigs and Calves and Experimental Infection of Gnotobiotic Pigs and Rodents

“…For Mycoplasma isolation, 50 l of cell culture medium from flasks with CAR bacillus growth were spread over the surface of agar plates prepared as previously described. 10 The plates were incubated in a candle jar (ϳ2-3% CO 2 ) at 37 C and examined for colony formation at 2-3-day intervals for 3 wk. Colonies were mixed with a drop of sterile cell culture medium on a microscope slide and covered with a coverslip.…”