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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

The objective was to examine the effect of pasture type, and of grazing compared with hay feeding, on milk production and quality from dairy goats in early and late grazing season. Eighty goats were grouped according to genotype and lactation, and randomly divided into two groups with approximately 8 weeks difference in kidding date and start of feeding experiment, in Early and Late grazing season. At the start of the feeding experiment the goats were divided into 4 forage-treatment groups: R,forest rangeland pasture; C, cultivated pasture; HH, high quality hay; HL, low quality hay. Group R yielded less milk (1.5 vs. 2.0 kg d–1) and lower milk protein content (32 vs. 33 g kg–1), but higher milk fat (46 vs. 37 g kg–1) and DM content (120 vs. 113 g kg–1) than group C. Free fatty acids (FFA) content in milk was not affected by pasture type. The effects of pasture type on milk yield and milk constituents were similar in early and late grazing season. Grazing resulted in similar milk yield but higher milk fat (42 vs. 34 g kg–1), protein (32 vs. 30 g kg–1) and DM (117 vs. 106 g kg–1) content, and lower content of FFA (0.22 vs. 0.34 mEq L–1) than hay feeding

Abstract

Ceratocystis polonica and Heterobasidion parviporum are important fungal pathogens in Norway spruce (Picea abies). Tree susceptibility to these pathogens with respect to phenology was studied using artificial fungal inoculations at six stages of bud development, and assessed by measuring phloem necroses in the stems of 2- and 8-year-old trees. Tree capacity for resistance was assessed by measuring phloem nonstructural carbohydrates at each stage. Phloem necroses were significantly larger in trees with fungal versus control inoculations and increased significantly over time. Changes in nonstructural carbohydrates occurred in the trees; a significant decline in starch and a slight but significant increase in total sugars occurred over time. These results suggest that susceptibility to fungal pathogens and carbohydrate levels in the stems of the trees were related to fine-scale changes in bud development. A trade-off may occur between allocation of starch (the major fraction of the stem carbohydrate pool) to bud development/shoot growth versus defence of the stem. Previous tests of plant defence hypotheses have focused on herbivory on plants growing under different environmental conditions, but the role of phenology and the effect of pathogens are also important to consider in understanding plant resource allocation patterns.