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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

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Abstract

The aim of this experiment was to investigate the effect of increasing the number of ewes per nipple drinker on water intake, feed intake and drinking behaviour of ewes. A group of 30 1¾ year old, pregnant ewes of the Norwegian Dala breed were exposed to three treatments, each treatment lasting one week: 7.5 ewes per nipple drinker (N7.5: four nipple drinkers), 15 ewes per nipple drinker (N15: two nipple drinkers) and 30 ewes peer nipple drinker (N30: one nipple drinker). The experiment was performed both in January (week 4–6, replicate 1) and replicated in April (week 13–15, replicate 2). The ewes were kept in insulated building and had free access to good quality hay. Water metres were connected to the pipeline for water supply and water wastage was collected and weighed. In addition, the daily intake of hay was recorded and the ewes were video recorded the three last days of each experimental period. Total drinking time per individual was calculated from observations of drinking behaviour from the video, as were also incidents of queuing and displacements. Both water and feed intake was higher in replicate 2 than in replicate 1. Increasing the number of individuals per nipple drinker had no effect on water intake in replicate 1, whereas in replicate 2 the water intake was (mean±SE) 3.5±0.3; 4.2±0.1 and 4.9±0.1 l/ewe and day in the treatments N7.5, N15 and N30, respectively (P<0.05). Regardless of replicate, the time spent drinking increased significantly when number of ewes per nipple drinker increased. Queuing was not affected by increasing the number of ewes per nipple drinker. In replicate 1 the number of displacements increased significantly when the number of individuals per nipple drinker increased (N7.5=7.6±1.7; N15=15.0±4.2 and N30=36.7±5.2; P<0.05) and the same trend could be seen in replicate 2, although not significant. In conclusion, one nipple drinker with an acceptable flow rate can serve up to 30 ewes without negatively affecting water and feed intake

Abstract

There is limited research about variations between cultivars for freezing tolerance in fruit crops and indeed much less is known about the distinctive in ground structure of the crown that herbaceous perennials depend on for regeneration in spring. Because strawberry is a representative species for the Rosaceae crops knowledge gained is expected to be transferrable to benefit improvement of many of these related crops. To gain insight into the molecular basis that may contribute to overwintering hardiness, a comparative proteomic analysis was carried out for four Fragaria x ananassa (octoploid strawberry) cultivars that differ in freezing tolerance. Protein expression was investigated in the overwintering relevant crown structure of strawberry from plants exposed to 0, 2, and 42 day cold treatments and were examined by two-dimensional gel electrophoresis (2D). Some proteins, such as molecular chaperones, antioxidants / detoxifying enzymes, metabolic enzymes, and pathogenesis related proteins were revealed to be at significantly higher levels before cold exposure in the most freezing tolerant cultivars, (‘Jonsok’ and ‘Senga Sengana’) compared to the least tolerant cultivars (‘Frida’ and ‘Elsanta’). Freezing tolerance was evaluated for the cultivars before and after cold exposure, with findings that support that the most freezing tolerant cultivars are poised for rapid adaptation to cold exposure, suggesting potential differences in capacity or rate for cold acclimation. Thus, the molecular basis for enhanced overwintering survival may be related to the elevated basal level of a number of proteins, many of which are known to confer stress tolerances. These findings are presented and overlaid with a LFQP shotgun analysis and microarray analysis. This study presents the largest quantitative proteomic data-set for strawberry crown tissue during cold exposure to date. Through the comparison of these cultivars that differ in freezing tolerance, proteins that may contribute to cold tolerance but lack significant cold induction were revealed.

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Abstract

To gain insight into the molecular basis contributing to overwintering hardiness, a comprehensive proteomic analysis comparing crowns of Fragaria × ananassa (octoploid strawberry) cultivars that differ in freezing tolerance was conducted. Four cultivars were examined for freeze tolerance and the most cold-tolerant cultivar (‘Jonsok’) and least tolerant cultivar (‘Frida’) were compared with a goal to reveal how freezing tolerance is achieved in this distinctive overwintering structure and to identify potential cold-tolerance associated biomarkers. Supported by univariate and multivariate analysis, a total of 63 spots from 2DE analysis and 135 proteins from label-free quantitative proteomics (LFQP) were identified as significantly differentially expressed in crown tissue from the two strawberry cultivars exposed to 0, 2, and 42 day cold treatment. Proteins identified as cold tolerance associated included molecular chaperones, antioxidants/detoxifying enzymes, metabolic enzymes, pathogenesis related proteins and flavonoid pathway proteins. A number of proteins were newly identified as associated with cold tolerance. Distinctive mechanisms for cold tolerance were characterized for two cultivars. In particular, the ‘Frida’ cold response emphasized proteins specific to flavonoid biosynthesis, while the more freezing tolerant ‘Jonsok’ had a more comprehensive suite of known stress responsive proteins including those involved in antioxidation, detoxification, and disease resistance. The molecular basis for ‘Jonsok’ enhanced cold tolerance can be explained by the constitutive level of a number of proteins that provide a physiological stress-tolerant “poise”.

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Abstract

There is increasing concern that the intensification of dairy production reduces the concentrations of nutritionally desirable compounds in milk. In this study we therefore compared important quality parameters (protein and fatty acid profiles, α-tocopherol and carotenoid concentrations) in milk from four dairy systems with contrasting production intensities (in terms of feeding regimes and milking systems). The concentrations of several nutritionally desirable compounds (β-lactoglobulin, omega-3 fatty acids, omega-3/omega-6 ratio, conjugated linoleic acid c9t11 and/or carotenoids) decreased with increasing feeding intensity (organic outdoor ≥ conventional outdoor ≥ conventional indoors). Milking system intensification (use of robotic milking parlours) had a more limited effect on milk composition, but increased mastitis incidence. Multivariate analyses indicated that differences in milk quality were mainly linked to contrasting feeding regimes, and that milking system and breed choice also contributed to differences in milk composition between production systems.