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Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2012

Abstract

In Norway, most lambs are slaughtered at the end of the grazing season in September. An increased demand for fresh meat during the off-season may change this pattern. Castration of male lambs is not permitted, and off-season slaughtering may affect the acceptability of the meat. The objective of this study was to determine the effect of gender on meat quality from Norwegian White Sheep lambs slaughtered in September at the age of five months. Twenty-nine male lambs and 46 female lambs were included in the experiment. Loin samples of M. Longissimus dorsi were analysed for sensory profile. Meat from male lambs had higher scores for the less pleasant sensory attributes of cloying (P < 0.05) and rancid (P = 0.08) flavour, and lower scores for the more pleasant attributes of sour and sweet taste (P < 0.05 for both attributes) compared to meat from female lambs. The differences were more apparent between lambs grazing ryegrass than between lambs fed a concentrate and roughage diet. It is concluded that even at the normal slaughtering time in September, significant differences between genders may occur.

Abstract

A crucial consideration for strawberry producers in Norway and other northern countries is winter freezing damage. A long-term goal of the Norwegian strawberry breeding is to increase winter hardiness and to improve fruit quality. Due to the complexity involved in regulating and enhancing freezing tolerance, the progress in the improvement of cultivars using traditional screening methods have had limited success. Thus, the development of molecular markers for freezing hardiness would facilitate the selection work for this trait. In this effort, we have developed and adopted state-of-art molecular tools to investigate cold response in strawberry plants during the acclimation phase resulting in the identification of a large number of genes, proteins, and distinct metabolites that correspond to cold/freezing tolerance in strawberry. To identify proteins responsible for freezing tolerance in strawberry we have examined alterations in protein levels in strawberry varieties that differ in cold tolerance using either 2-DE gel analysis followed by LC-MS/MS analysis or a shotgun MS/MS approach. Proteomic analysis suggested 30 potential biomarkers that showed significant changes in the cultivated strawberry in response to cold. In addition, GC-MS-based metabolite profiling revealed the up-regulation of carbohydrates, polyols, amino acids, TCA intermediates, and other distinct secondary metabolites after cold treatment. Transcriptional analysis of the cold acclimated samples also confirmed the regulation upon cold-treatment with varietal differences in strawberry. Moreover, several F2-populations from the model F. vesca parents diverging in cold tolerance have been developed in order to facilitate mapping of QTLs by performing GBS analyses. The knowledge attained from these endeavors is expected to expedite breeding of strawberries to achieve freezing tolerant lines and provide an integrative understanding of the molecular pathways that underlie this characteristic. * Rohloff et al. (2012) Metabolite profiling reveals novel multi-level cold responses in the model Fragaria vesca. Phytochemistry 79:99-109. * Koehler et al. (2012) Proteomic study of low temperature responses in strawberry cultivars (Fragaria x ananassa) that differ in cold tolerance. Plant Physiology 159:1787–1805 * Davik et al., (2012) Low temperature tolerance in diploid strawberry species (Fragaria ssp.) and its correlation to alcohol dehydrogenase levels, dehydrin levels, and central metabolism constituents. Planta (in press; DOI: 10.1007/s00425-012-1771-2).