RESUMEN
We have developed 21 dinucleotide repeat microsatellite loci from African populations of Psyttalia lounsburyi (Silvestri) (Hymenoptera: Braconidae), a parasitoid wasp of the olive fruit fly, as part of a study assessing the role of introgression/hybridization in the success of a biological control introduction. We proposed suitable conditions for polymerase chain reaction multiplexing. All 21 loci were polymorphic with two to 21 alleles per locus within the Kenyan and South African populations tested. Most of them were successfully amplified in two other Psyttalia species.
RESUMEN
The occurrence of outbreaks of peste des petits ruminants (PPR) in three districts of Tajikistan is described. The causal strain (PPR Tajikistan) was characterized and the sequence of its N gene was compared with that of 43 other strains isolated since 1968 in Africa, the Middle East and Asia. The study demonstrated (1) the value of the N gene as a target in comparing isolates obtained over an extended period of evolution, and (2) that clustering was related to the geographical origin of strains.
Asunto(s)
Brotes de Enfermedades/veterinaria , Peste de los Pequeños Rumiantes/epidemiología , Virus de la Peste de los Pequeños Rumiantes/aislamiento & purificación , Animales , Antígenos Virales/inmunología , Secuencia de Consenso , Ensayo de Inmunoadsorción Enzimática/veterinaria , Femenino , Cabras , Masculino , Peste de los Pequeños Rumiantes/patología , Peste de los Pequeños Rumiantes/virología , Virus de la Peste de los Pequeños Rumiantes/genética , Virus de la Peste de los Pequeños Rumiantes/inmunología , ARN Viral/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Estudios Seroepidemiológicos , Ovinos , Tayikistán/epidemiologíaRESUMEN
A rapid and specific test was developed for the diagnosis of peste des petits ruminants disease. This assay is based on the rapid purification of RNA on glass beads followed by the reverse transcription-polymerase chain reaction (RT-PCR). To that effect, a set of primers (NP3/NP4) was used to amplify specifically a fragment of about 350 bp in the 3' end of the RNA messenger that encodes the nucleocapsid protein of the peste des petits ruminants virus. The PCR-product was detected by UV illumination after electrophoresis on agarose gel or by hybridisation with a digoxigenin-11-dUTP labelled oligonucleotide probe after a blot transfer. In comparison with the conventional titration technique on Vero cells, this RT-PCR assay was 1000-fold more sensitive. Compared with the popular Chomczynski and Sacchi's method [Anal. Biochem. 162 (1987) 156], the purification of the RNA on the glass beads offers the advantage of being more rapid and also avoiding the use of solvents.