Ioan Pasca

Genetic Characterization of Bombyx mori (Lepidoptera: Bombycidae) Breeding and Hybrid Lines With Different Geographic Origins

Abstract The domesticated silkworm Bombyx mori L. comprises a large number of geographical breeds and hybrid lines. Knowing the genetic structure of those may provide information to improve the conservation of commercial lines by estimating inbreeding over generations and the consequences of excessive use of those lineages. Here, we analyzed the genetic diversity of seven breeds and eight hybrid lines from Eastern Europe and Asia using highly polymorphic microsatellites markers to determine its genetical impact on their use in global breeding programs. No consistent pattern of deviation from Hardy–Weinberg equilibrium was found for most breed and hybrids; and the absence of a linkage disequilibrium also suggests that the strains are in equilibrium. A principal coordinate analysis revealed a clear separation of two silkworm breeds from the rest: one (IBV) originated from India and the other one (RG 90 ) from Romania/Japan. The tendency of the other breeds from different geographic origins to cluster together in a general mix might be due to similar selection pressures (climate and anthropogenic factors) in different geographic locations. Phylogenetic analyses grouped the different silkworm breeds but not the hybrids according to their geographic origin and confirmed the pattern found in the principal coordinate analysis.

Aspects Regarding the Evaluation of the Microbiological Status of the Minced Meat Products From a Processing Unit

Minced meat and processed meat are raw products that are very susceptible to all microbiological factors to which they are exposed. In this sudty, 108 samples were analyzed during two years. The results have revaled the contamination following the human factor (1 case of Salmonella contamination at processed meat), respectivelly the high bacteria load in minced meat revealed by the Total Germ Count (TGC) and Escherichia coli values. These results were due to the semi-automatic packaging process (samples 1 - 42) and their significant decrease after the introduction of an automatic packaging system (samples 43-58). The conclusion of our study was that the packaging technology which limits the human contact and the environment surfaces contact ensures a safer product for the consumer.