Experimental infection with Mycoplama galliseptioum in chikens, turkeys, laying hens and chick embryos

Le pouvoir pathogène de la souche Mycoplasma gallisepticum R est exacerbé par 10 passages successifs sur poulets exempts d’organismes patho gènes spécifiés (EOPS). La souche réisolée MGR P10 est inoculée à des pou lets et des dindonneaux EOPS, des poules pondeuses conventionnelles et des embryons de poule de 19 jours d’incubation. Les symptômes et lésions observés chez ces hôtes révèlent le tropisme respiratoire et le fort pouvoir pathogène de la souche MGR P10. Un léger décrochement de la courbe de ponte est enregistré chez les poules pondeuses et une mortalité impor tante et rapide est observée après inoculation à l’embryon de 19 jours. Le pouvoir de diffusion de la souche est également mis en évidence.The Mycoplasma gallisepticum R strain is serially passaged ten times through specific pathogen free (SPF) chickens in order to exacerbate its potential pathogenicity. The recovered MGR P10 strain is inoculated in SPF chickens and turkeys, commercial laying fowl and nineteen-day-old chick embryos. The inoculation induces general and respiratory symptoms in the different hosts. Mortality occurs in the chicks hatched from inoculated embryos. A drop in egg production is observed in the laying hens. The strain is also shown to be able to spread from bird to bird

Reproduction expérimentale de mycoplasmose à Mycoplasma gallisepticum chez le poulet, le dindonneau, la poule pondeuse et l’embryon de poule

Experimental infection with Mycoplasma gallisepticum in chickens, turkeys, laying hens and cluck embryos. The Mycoplasma gallisepticum R strain is serially passaged ten times through specific pathogen free (SPF) chickens in order to exacerbate its potential pathogenicity. The recovered MGR P10 strain is inoculated in SPF chickens and turkeys, commercial laying fowl and nineteen-day-old chick embryos. The inoculation induces general and respiratory symptoms in the different hosts. Mortality occurs in the chicks hatched from inoculated embryos. A drop in egg production is observed in the laying hens. The strain is also shown to be able to spread from bird to bird.Le pouvoir pathogène de la souche Mycoplasma gallisepticum R est exacerbé par 10 passages successifs sur poulets exempts d’organismes pathogènes spécifiés (EOPS). La souche réisolée MGR P10 est inoculée à des poulets et des dindonneaux EOPS, des poules pondeuses conventionnelles et des embryons de poule de 19 jours d’incubation. Les symptômes et lésions observés chez ces hôtes révèlent le tropisme respiratoire et le fort pouvoir pathogène de la souche MGR P 10. Un léger décrochement de la courbe de ponte est enregistré chez les poules pondeuses et une mortalité importante et rapide est observée après inoculation à l’embryon de 19 jours. Le pouvoir de diffusion de la souche est également mis en évidence.Kempf Isabelle, Ollivier Claudine, Protais Jocelyne, Guittet Michèle, Cacou P.M., L'Hospitalier Rollande, Bennejean Georges, Morin Yannick, Quintin E., Lecocq L. Reproduction expérimentale de mycoplasmose à Mycoplasma gallisepticum chez le poulet, le dindonneau, la poule pondeuse et l’embryon de poule. In: Bulletin de l'Académie Vétérinaire de France tome 142 n°1, 1989. pp. 51-62

Direct evidence of weakly dispersed and strongly anharmonic optical phonons in hybrid perovskites

International audienceHybrid organolead perovskites (HOP) have started to establish themselves in the field of photovoltaics, mainly due to their great optoelectronic properties and steadily improving solar cell efficiency. Study of the lattice dynamics is key in understanding the electron-phonon interactions at play, responsible for such properties. Here, we investigate, via neutron and Raman spectroscopies, the optical phonon spectrum of four different HOP single crystals: MAPbBr3, FAPbBr3, MAPbI3, and α-FAPbI3. Low temperature spectra reveal weakly dispersive optical phonons, at energies as low as 2-5 meV, which seem to be the origin of the limit of the charge carriers mobilities in these materials. The temperature dependence of our neutron spectra shows as well a significant anharmonic behaviour, resulting in optical phonon overdamping at temperatures as low as 80 K, questionning the validity of the quasi-particle picture for the low energy optical modes at room temperature where the solar cells operate

Performance and Tolerance of a Protocol for Idiopathic Chronic Greasy Seborrhea in 18 Dogs Using a Shampoo and Mousse Containing Plant Extracts

The study aimed to evaluate the tolerance, performance and effect on hair lipids and skin hydration of a protocol combining applications of one shampoo and subsequent mousses containing plant extracts (Ophytrium and Seboliance) in dogs with an undiagnosed chronic greasy keratinisation disorder. Six dogs were washed with plain water on day (D)0. Twelve dogs were shampooed on D0 and received eight mousse applications at 48–72 h intervals from D2 to D18. Clinical score (CS), Natural Moisturizing Factors (NMF) and hair lipids (HL) were evaluated on D0, D0 + 4 h, D7, D14 and D24. At baseline, no significant differences were observed in CS, NMF and HL between groups. In the control group, CS and HL remained stable throughout the study while a slight decrease in NMF was observed at D0 + 4 h. CS was significantly reduced in the test group between D0 and D7 (−53%) which reached 91% at D24 (p < 0.05), with no side effects. NMF levels decreased in the test group at D0 + 4 h (−73%, p < 0.0001) and returned to baseline from D14. In conclusion, one shampoo and subsequent mousse applications rapidly and safely improved coat quality in dogs with an undiagnosed keratinisation disorder without affecting NMF and HL contents over the study period

Performance and Tolerance of a Protocol for Idiopathic Chronic Greasy Seborrhea in 18 Dogs Using a Shampoo and Mousse Containing Plant Extracts

The study aimed to evaluate the tolerance, performance and effect on hair lipids and skin hydration of a protocol combining applications of one shampoo and subsequent mousses containing plant extracts (Ophytrium and Seboliance) in dogs with an undiagnosed chronic greasy keratinisation disorder. Six dogs were washed with plain water on day (D)0. Twelve dogs were shampooed on D0 and received eight mousse applications at 48–72 h intervals from D2 to D18. Clinical score (CS), Natural Moisturizing Factors (NMF) and hair lipids (HL) were evaluated on D0, D0 + 4 h, D7, D14 and D24. At baseline, no significant differences were observed in CS, NMF and HL between groups. In the control group, CS and HL remained stable throughout the study while a slight decrease in NMF was observed at D0 + 4 h. CS was significantly reduced in the test group between D0 and D7 (−53%) which reached 91% at D24 (p p < 0.0001) and returned to baseline from D14. In conclusion, one shampoo and subsequent mousse applications rapidly and safely improved coat quality in dogs with an undiagnosed keratinisation disorder without affecting NMF and HL contents over the study period

Genome Sequence of the Sulfate-Reducing Bacterium Desulfotomaculum hydrothermale Lam5(T).

International audienceHere, we report the draft genome sequence of Desulfotomaculum hydrothermale, a sulfate-reducing, spore-forming bacterium isolated from a Tunisian hot spring. The genome is composed of 2.7 Mb, with a G+C content of 49.48%, and it contains 2,643 protein-coding sequences

Prokaryotes and evolution

In natural world, no organism exists in absolute isolation, and thus every organism must interact with the environment and other organisms. Next-generation sequencing technologies are increasingly revealing that most of the cells in the environment resist cultivation in the laboratory and several prokaryotic divisions have no known cultivated representatives. Based on this, we hypothesize that species that live together in the same ecosystem are more or less dependent upon each other and are very large in diversity and number, outnumbering those that can be isolated in single-strain laboratory culture. In natural environments, bacteria and archaea interact with other organisms (viruses, protists, fungi, animals, plants, and human) in complex ecological networks, resulting in positive, negative, or no effect on one or another of the interacting partners. These interactions are sources of ecological forces such as competitive exclusion, niche partitioning, ecological adaptation, or horizontal gene transfers, which shape the biological evolution. In this chapter, we review the biological interactions involving prokaryotes in natural ecosystems, including plant, animal, and human microbiota, and give an overview of the insights into the evolution of living beings. We conclude that studies of biological interactions, including multipartite interactions, are sources of novel knowledge related to the biodiversity of living things, the functioning of ecosystems, the evolution of the cellular world, and the ecosystem services to the living beings

Importance of lattice softness and phonon anharmonicity for the optoelectronic properties of 3D, 2D and 0D halide perovskites

National audienc

Importance of lattice softness and phonon anharmonicity for the optoelectronic properties of 3D, 2D and 0D halide perovskites

National audienc