A proteomic approach to study local chicken breeds characterization

Aim of this study is to apply a proteomic approach for characterization of local chicken breeds. The experiment involved a total of 29 males of P\ue9poi, Padovana, and Ermellinata local chicken breeds. Sarcoplasmic protein fractions of breast muscle were analysed by bidimensional electrophoresis. Image analysis followed by statistical analysis enabled to differentiate groups of individuals on the similarities of protein expression. Individuals were distinguished into clusters and groups, corresponding to the breed of origin. Results evidenced a possible utilisation of proteomic approach in the field of breed characterization studies as an alternative to genomic analyses performed using molecular markers, both for breed and product traceability purposes

Are one early muscle pH and one early temperature measurement sufficient to detect PSE breast meat in turkeys?

International audienceWithin a large flock of turkey toms (2000 BUT9 conventionally reared and slaughtered), early muscle pH measurements were randomly done to distinguish two groups of birds presenting low (fast glycolyzing, GR) or normal (normal glycolyzing, GN) values. Subsequently, ultimate pH values and meat quality parameters were also recorded. Meat quality parameters from GR or GN samples differ more or less indicating more or less severe PSE conditions. Proteins extracted from the samples at 20 min post mortem were quite similar while they largely differ at 24 h post mortem. Moreover, among the GR birds, a subgroup of animals (called AB) presented SDS-PAGE profiles largely different from other GR or GN birds. All the subsequent analysis developed on meat quality parameters as well as for protein extractabilities also differ between AB and other animals indicating that they must be considered differently in term of PSE syndrome development. Western blots against Myosin Heavy Chain and actin at 24 h post mortem indicate that myofibrillar proteins alterations are different in AB and GR or GN samples. At 20 min post mortem, glycogen content was the lowest in AB samples while the glycolytic potential was similar in all samples at the time of death. Measurements of PFK enzyme specific activity did not indicate a different regulation of post mortem glycolysis in AB samples. Our results suggest that a unique pH measurement at 20 min post is insufficient to detect animals the more prone to develop a severe PSE syndrome in turkeys. In consequence, it is suggested that a more precise evaluation of the kinetic of pH and temperatures fall has to be conducted to better understand the etiology of meat quality parameters alterations in poultry

Current advances in proteomic analysis of (fatty) liver

Biochemical Research MethodsInternational audienceIn this review, an overview on proteomic studies conducted in livers of farm animals is conducted with a special focus on liver steatosis in waterfowl. Several studies had interest in understanding liver metabolism in dairy cows under various conditions (e.g. fasting) or the evolution of liver proteome during embryonic phases or growing periods in chicken. Those studies provide interesting results leading to a better understanding of the liver metabolism. Liver steatosis development in waterfowl represents a special case and a focus on proteomic studies conducted in these birds will be done. Indeed, recent studies aimed at resolving protein evolution during overfeeding in duck. Proteomic analysis combining two complementary approaches (2-dimensional electrophoresis gels and shot gun strategy) in order to better understand the mechanisms underlying the variability of cooking yield of fatty liver will be presented

Using 2-DE for the differentiation of local chicken breeds

The aim of this study was to apply a proteomic approach for the characterisation of local chicken breeds. The experiment involved a total of 29 males of three local Italian chicken breeds: Pe\ub4poi, Padovana and Ermellinata di Rovigo. Sarcoplasmic protein fractions of breast muscle were analysed by 2-DE. Image analysis followed by statistical analysis enabled to differentiate groups of individuals based on the similarities of protein expression. Individuals were distinguished into clusters and groups, corresponding to the breed of origin. Distances among individuals, calculated using data on spot volumes, were used to draw a neighbourjoining tree, showing clear individual and breed grouping. The most relevant spots regarding breed differentiation were detected; 11 were identified by MS revealing preliminary evidences on the mechanisms of the breed differentiation process. The results evidenced the ability of proteomic analyses for the characterisation of chicken breeds

Analyse protéomique du Pectoralis major de 2 types génétiques de dindes

National audienceDans une étude précédente, nous avons mis en évidence une meilleure aptitude à la transformation des viandes de dindes label Rouge (LR) (Molette et al., 2005). Celle-ci pouvait être mis en relation avec un meilleur pouvoir tampon ainsi que de meilleures extractabilités des protéines sarcoplasmiques et myofibrillaires pour les LR (Molette et al., 2005). Dans la présente étude, nous avons voulu comprendre quelles étaient les protéines impliquées et nous avons choisi une approche protéomique. L’analyse protéomique est une approche largement utilisée dans les sciences de la vie pour caractériser et étudier une population de protéines dans un échantillon biologique. L’analyse protéomique se déroule en plusieurs étapes incluant la séparation et la visualisation des protéines en utilisant l’électrophorèse bidimensionnelle (2-DE), la comparaison des gels obtenus, l’excision et l’identification des protéines d’intérêt en utilisant la spectrométrie de masse et la recherche dans les bases de données (Hayduk et al., 2002). Nous avons utilisé cette approche pour comparer les gels 2-DE obtenus à partir de muscles Pectoralis major de 2 types génétiques de dindes : BUT9 et LR