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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 of the present study was to examine the effect of grazing on different pasture types and hay feeding on dairy goat milk fatty acid (FA) composition in early and late grazing season. Eighty goats were grouped according to genotype and lactation, and randomly divided into two groups (Early and Late) with approximately 8 weeks difference in mating and kidding dates. Goats within each of the two groups were further allocated to four forage treatment groups: R, forest rangeland pasture; C, cultivated pasture; HH, high quality hay; HL, low quality hay. The goats in Early were subjected to forage treatments in early grazing season, while the goats in Late received the forage treatments 8 weeks later. The most abundant FAs were C16:0 and C18:1c9 followed by C14:0 and C18:0. The milk proportion of the short and medium chained fatty acids (C6:0-C14:0) and C16:0 was higher (P < 0.0001) in Late than in Early grazing season, whilst the proportion of long chained FAs (C18:0, C18:1c9, C18:1t11, C18:2c9, 12, C18:2c9t11 and C18:3c9, 12, 15) were lower (P < 0.001). Goats grazing R yielded less milk (1.5 vs. 2.0 kg/d, P < 0.001) but with higher milk fat content (46 vs. 37 g/kg, P < 0.001) than C. The milk from goats on R had lower (P < 0.01) proportion of medium chained FAs (C10:0-C14:0) and C18:2c9, t11 but higher (P < 0.05) proportion of C18:0, C18:2c9,12 and C20:0 than C. Grazing compared to hay gave milk with lower proportion of medium chained FAs (C12:0-C14:0) and C16:0 but higher proportion of the long chained FAs C18:0, C18:1t11, C18:3c9, 12, C18:2c9, t11, C18:3c9, 12, 15, C20:0 than hay feeding. Higher supply of energy may explain higher proportion of de novo synthesised low and medium chained FA and lower proportion of long chained FA on C than on R, whilst higher supply of FA from mobilized fat may explain higher milk proportion of long chain FA in Early than in late season. Moreover, goats on pasture had likely higher supply of FA from dietary fat, which explain higher milk proportion of the long chained FA than on hay.

Abstract

The agro-ecosystems (e.g. cropping system (tunnel/ greenhouse/ open field, etc.), plant species, cultivar, soil management (fertilization, pH, soil cover, etc.)) has an impact on pests (insects, mites, snails, nematodes, plant diseases and weeds) and the control strategies used. Biological control agents (BCA) can serve as alternatives or as supplements to chemical pesticides. They can reduce the need for chemical treatments and thus the risk of non-target effects to humans and the environment from pesticide use. Further, the use of BCA might help to reduce the risk of pesticide resistance development. The Regulation and use of BCA differs significantly between different European countries, especially for the macroorganisms (insects, mites and nematodes). Norway has its own regulation for macroorganisms, while regulation of microorganisms (fungi, bacteria, viruses and protozoa) is almost the same as for chemical pesticides, and is comparable to the EU regulations. There is a wide range of biological control products available on the international market, and access to these products would benefit Norwegian growers. Norway has, however, a very limited selection of registered biological control products. A new Norwegian project titled “Increasing the use of biological control agents of plant pests” is financed by the Norwegian Ministry of Agriculture and Food. In this project we try to identify the bottlenecks and propose solutions to promote the registration and increase the use of BCA in Norway. A survey has been conducted where experts and agricultural advisors on different cropping systems were asked to prioritize which BCA (products) on the European market should be promoted and registered in Norway (initially against pest insects and mites). Preliminary results from this project will be presented.