@misc{orgprints6096,
           title = {Mineralinnhold i planter og mineralforsyning til dr{\o}vtyggere i {\o}kologisk landbruk},
        abstract = {28 {\o}kologiske g{\r a}rder er med i forskningsprogrammet. G{\r a}rdene representerer b{\r a}de kyst-og innlandsklima og forskjellige jordsmonnstyper. 
Sommeren 2001 og 2002 ble matjordas og engas innhold av makromineralene fosfor (P), svovel (S), magnesium (Mg), natrium (Na), kalsium (Ca), kalium (K) og klor (Cl) og mikromineralene selen (Se), kobolt (Co), molybden (Mo), kopper (Cu), mangan (Mn), jern (Fe) og sink (Zn). Resultatene skal bl.a vurderes opp mot klima, berggrunn, jordsmonn, jordpakking og dyras behov for mineraler ved forskjellige avdr{\r a}ttsniv{\r a}er. 
Mars/april 2002 ble det tatt ut blodpr{\o}ver av dyrene p{\r a} noen av sau- og kug{\r a}rdene for {\r a} vurdere dyras forsyning av selen, kopper og E-vitamin. Det utf{\o}res fors{\o}k med f{\^o}ring av organisk selen til sau og mj{\o}lkekyr. Sammen med Canadiske forskningsmilj{\o} utvikles en metode for Se-analyser ved sv{\ae}rt lave Se-konsentrasjoner i pr{\o}vematerialet. Det gjennomf{\o}res et pottefors{\o}k for {\r a} unders{\o}ke transpirasjonens effekt p{\r a} Se-opptak av selenat og selenitt i hvete. 
Sommeren 2004 og 2005 gjennomf{\o}res feltfors{\o}k med tilleggsgj{\o}dsling av lettl{\o}selig svovel og kalium. Aktuelle gj{\o}dselkilder pr{\o}ves ogs{\r a} ut i pottefors{\o}k. Resultatene skal innarbeides i gj{\o}dselplanleggingsprogram for {\o}kologisk landbruk. 
},
             url = {https://orgprints.org/id/eprint/6096/},
        keywords = {minerals; fodder; micro nutrients; macro nutrients;  mineraler; selvforsyning; self-sufficiency; MINERALSIP}
}

@phdthesis{orgprints6923,
          author = {Espen Govasmark},
           title = {Trace element status of soil and organically grown herbage in relation to animal requirements},
            year = {2005},
          school = {Norwegian University of Life Sciences},
       publisher = {Norwegian University of Life Sciences},
        keywords = {Organic farming, Zinc, Iron, Manganese, Copper, Molybdenum, Cobalt, Selenium, Vitamin E, Dairy cattle, sheep, soil, herbage, trace element, MINERALSIP},
             url = {https://orgprints.org/id/eprint/6923/},
        abstract = {To obtain a general picture of the herbage zinc (Zn), iron (Fe), manganese (Mn), copper (Cu), molybdenum (Mo), cobalt (Co) and selenium (Se) concentrations on organic livestock farms, we analysed soil (2001) and herbage (2001 and 2002) samples from 28 farms from four regions in Norway. We analysed animal blood plasma Cu, B12 (Co), {\ensuremath{\alpha}}- and {\ensuremath{\gamma}}-tocopherol (vitamin E) and whole blood Se to investigate if the farms feeding practice met the dietary need of Cu, Co, Se and vitamin E in animals. 

The first cut herbage median (10th-90th percentile) Zn, Fe, Mn, Cu, Mo, Co and Se concentrations were 19 (14-34), 50 (36-88), 34 (22-86), 5.3 (3.9-6.8), 1.5 (0.6-4.8), {\ensuremath{<}}0.05 ({\ensuremath{<}}0.05-0.08) and {\ensuremath{<}}0.01 ({\ensuremath{<}}0.01-0.03) mg kg-1 DM, respectively. The herbage trace element concentration was generally higher in the second cut. The second cut herbage median (10th-90th percentile) Zn, Fe, Mn, Cu, Mo, Co and Se concentrations were 21 (16-37), 84 (52-171), 66 (36-205), 7.0 (5.7-9.3), 3.3 (1.6-10.1), 0.06 ({\ensuremath{<}}0.05-0.15) and 0.02 ({\ensuremath{<}}0.01-0.06) mg kg-1 DM, respectively. The plasma Cu and B12 (except one sheep herd) concentration were within the suggested normal range set by the Norwegian Veterinary Institute. Whole blood Se concentrations were 0.10 (0.04-0.15) ?g g-1 in dairy cattle and 0.14 (0.03-0.26) ?g g-1 in sheep. Vitamin E concentrations were 4.2 (2.7-8.4) mg L-1 in dairy cattle and 1.3 (0.9-2.4) mg L-1 in sheep. 

The results of mixed model analyses of herbage Zn, Fe, Mn, Cu and Mo indicated that soil pH, soil texture, botanical composition and phenological stage at harvest mostly influenced the herbage trace element concentrations within regions. There was a poor relationship between soil and herbage trace element concentrations, except for Zn. None of the soil and plant variables explained the variation in the herbage Se or Co concentration, but the number of samples was too low to draw clear conclusions on these two elements. There were some differences in soil and herbage trace element concentrations between regions.

It was generally concluded that Zn, Fe, Mn, Cu and Mo did not limit plant growth. The herbage concentrations of Fe, Mn, Cu and Mo were sufficient to meet the dietary needs of ruminants. The herbage Zn concentration was insufficient to meet the dietary needs of dairy cattle. The herbage Co and Se concentrations and the Cu/Mo ratio were not alone balanced to meet the dietary needs of ruminants. The on-farm feeding practises fulfilled the dietary needs of Cu and Co. Selenium contents were generally insufficient on dairy farms under prevailing feeding regimes, whereas the vitamin E was insufficient on sheep farms. It is therefore highly recommended to use trace element mixtures and/or concentrates fortified with Cu, Co, Se and vitamin E on Norwegian organic livestock farms. 

Most open vessel digestion procedures of biological material utilize a mixture of acids that include perchloric acid. There have been many accidents associated with the use of perchloric acid where serious injury has resulted. Therefore, a microwave digestion procedure of biological material, avoiding the use of perchloric acid while maintaining accurate selenium recoveries, was developed. Biological material was digested in two steps using nitric acid followed by hydrogen peroxide. Following the addition of phosphoric acid, remaining nitric acid and hydrogen peroxide were removed by evaporation, and Se-oxides were reduced to selenite using hydrochloric acid. Samples were adjusted to a buffered pH of 1.75 and reacted with 2,3-diaminonaphthalene. The resulting piazselenol complex was extracted into cyclohexane. A normal phase HPLC method, using an amino phase column and a cyclohexane/ethyl acetate mobile phase, was used to separate the piazselenol complex from any remaining impurities before fluorescence detection on a HPLC-FLD. The relationship between peak height and selenium concentration was linear between 0 and 2 mg L-1. The mass detection limit of the complete procedure was 0.29 ng of selenium. Recoveries of Se were within the certified range for the material analysed. 

A pot experiment was used to investigate the relationship between ammonium-nitrate and selenate in the wheat uptake and leaching water loss of Se. Ammonium-nitrate was applied by two methods, (i) entire dose at sowing (ii) in split application as 75 \% at sowing and 25 \% at stem elongation. Selenate was applied at sowing, tillering, stem elongation, head emergence and at milking growth stage. Split N application increased the protein content and Se concentration in grain, but decreased the Se concentration in leaf and straw. The highest Se concentration in the plant was achieved when the soil N potentially was highest. The Se leaching losses increased with response uptake by plants, being highest at highest Se uptake by plants, but decreasing with split N application.


Conclusions of the work:
?	Supplement of Cu, Co, Se and vitamin E are recommended to both dairy cattle and sheep and Zn to dairy cattle in organic husbandry in Norway. 

?	It is possible to determine Se in biological material without use of perchloric acid. 

?	Applying selenate and ammonium-nitrate together after tillering increases the wheat grain Se concentration and total Se uptake, split N application having the lowest leaching losses of Se.
}
}

@misc{orgprints6110,
          volume = {55},
         journal = {Acta Agriculturae Scandinavica Section B - Soil and Plant Science},
       publisher = {Taylor \& Francis},
          author = {Espen Govasmark and Arvid Steen and Anne Kjersti Bakken and Turid Str{\o}m and Sissel Hansen},
           title = {Factors affecting the concentration of Zn, Fe and Mn in herbage from organic farms and in relation to dietary requirements of ruminants},
            year = {2005},
           pages = {131--142},
        keywords = {animal nutrition, dairy cattle, feed, micronutrient, roughage, sheep, soil, trace element, MINERALSIP},
             url = {https://orgprints.org/id/eprint/6110/},
        abstract = {To obtain a general picture of the herbage zinc, iron and manganese concentrations and their relation to dietary requirements of ruminants on organic farms, we analysed soil and herbage samples from four regions in Norway. The soil median Zn, Fe and Mn concentrations were 0.18, 13 and 0.84 mg/L, respectively. The herbage median (10th-90th percentile) Zn, Fe and Mn concentrations (mg/kg) in herbage in the first cut were 19 (14-34), 50 (36-88), 34 (22-86) and in the second cut 21 (16-37), 84 (52-171) and 66 (36-205), respectively. The results of mixed model analysis of herbage Zn, Fe and Mn indicate that soil pH, soil texture, soil mineral concentration and botanical composition are the most influencing factors. We conclude that Zn, Fe and Mn did not limit plant growth, and that the herbage concentrations except for Zn, were sufficient to meet the dietary needs of ruminants on organic dairy farms.}
}

@inproceedings{orgprints6935,
           title = {Mikromineralinnhold i jord og planter - mikromineralforsyning til dr{\o}vtyggere i {\o}kologisk landbruk},
          volume = {8},
         journal = {Gr{\o}nn kunnskap},
          number = {2},
          author = {Espen Govasmark and Arvid Steen and Anne Kjersti Bakken and Turid Str{\o}m and Sissel Hansen},
            year = {2005},
           pages = {155--162},
       publisher = {Planteforsk Apelsvoll forskningssenter},
        keywords = {Mikromineral, jern, kopper, mangan, sink, cobolt, selen, vitamin E, molybden, grovf{\^o}r, dr{\o}vtyggere, sau, ku, MINERALSIP},
        abstract = {Det var generelt et h{\o}gere innhold av de enkelte mikromineralene i andre sl{\r a}tt enn i f{\o}rste sl{\r a}tt. Flere av plantepr{\o}vene viste s{\r a} lavt innhold av sink at det kan redusere avlingsniv{\r a}et. Mikromineralinnholdet i kl{\o}ver var h{\o}yere enn i den samlede fraksjonen av gras, kl{\o}ver og urter, slik at {\o}kt kl{\o}verinnhold i enga er viktig for {\r a} {\o}ke innholdet av mikromineraler i f{\^o}ret Ut fra mineralbehovet hos sau- og storfe viste plante- og blodpr{\o}ver at flere av besetningene hadde for liten tilf{\o}rsel av selen og E-vitamin, mens tilf{\o}rselen av kobolt og kopper stort sett var tilfredsstillende. },
             url = {https://orgprints.org/id/eprint/6935/}
}

@misc{orgprints6922,
           title = {Status of selenium and vitamin E on Norwegian organic sheep and dairy cattle farms},
          author = {Espen Govasmark and Arvid Steen and Turid Str{\o}m and Sissel Hansen and Bal Ram Singh and Aksel Bernhoft},
            year = {2005},
           pages = {40--46},
         journal = {Acta Agriculturae Scandinavica, Section A Animal Science},
          volume = {55},
       publisher = {Taylor \& Francis},
        abstract = {Herbage selenium (Se) concentration is generally low in Norway. It is unknown, if feeding practises on Norwegian organic farms fulfil the dietary need of Se and vitamin E to sheep and dairy cattle. Therefore, we analysed Se in soil and herbage, and Se and vitamin E in animal blood in the indoor feeding season at 14 organic dairy and 14 organic sheep farms. The herbage Se concentration was low. Approximately 50 and 35 \% of all samples in the first and second cut, respectively, had Se concentrations below the detection limit of 0.01 mg/kg dry matter (DM). The median (10th, 90th percentile) Se concentrations were {\ensuremath{<}}0.01 ({\ensuremath{<}}0.01, 0.03) and 0.02 ({\ensuremath{<}}0.01, 0.06) mg/kg DM in the first and second cuts, respectively. Whole blood Se concentrations were 0.10 (0.04, 0.15) ?g/g in dairy cattle and 0.14 (0.03, 0.26) ?g/g in sheep. Vitamin E concentrations were 4.2 (2.7, 8.4) mg/L in dairy cattle and 1.3 (0.9, 2.4) mg/L in sheep. None of the soil or plant variables explained the variation in herbage Se concentration, although Se in soil and plant tended to be correlated. Herbage Se concentration was inadequate to meet the dietary Se requirements. Vitamin E requirement was only met in dairy herds. We recommend Se and vitamin E supplementation to ruminants on organic farms.},
             url = {https://orgprints.org/id/eprint/6922/},
        keywords = {feed, mineral nutrition, organic farming, roughage, Se, soil, MINERALSIP}
}

@inproceedings{orgprints11946,
       publisher = {ISOFAR},
          editor = {Daniel Neuhoff},
            year = {2008},
           pages = {160--163},
          author = {Sissel Hansen and Anne Kjersti Bakken},
          volume = {II},
         journal = { Proceedings of the 2nd scientific conference of the international society of organic agriculture research (ISOFAR), Livestock, socio-economic and cross disciplinary research in organic agriculture},
           title = {A discussion of norms for S supply in organic farming based on content in forage and ruminant performance in Norway},
             url = {https://orgprints.org/id/eprint/11946/},
        abstract = {The content of sulphur (S) in grassland on 27 Norwegian organic farms with dairy or sheep production was investigated in 2001 and 2002. The forage content of S was below the norms (2 g S kg DM-1) for both plants and animals in a large proportion of the samples. The average S content in forage at dairy farms was 1.4 g S kg DM-1 and at sheep farms 1.5 g. Even on grasslands with low plant S content ({\ensuremath{<}}1 g S kg DM-1), S-fertilization did not increase yields and increased the plants? S content only very slightly. No indications of S deficiency were observed on the dairy farms. For one sheep farm with a forage S content of 1.1 {$\pm$} 0.1g S kg DM-1, brittle and short winter wool was reported.},
        keywords = {forage, dairy cattle, deficiency, grassland, ruminant, sheep, mineralsip}
}

@misc{orgprints15238,
          author = {Arvid Steen and Turid Str{\o}m and Aksel Bernhoft},
           month = {March},
            year = {2008},
           pages = {1--4},
           title = {Organic selenium supplementation increased selenium concentrations in ewe and newborn lamb blood and in slaughter lamb meat compared to inorganic selenium supplementation
},
          volume = {50},
         journal = {Acta Veterinaria Scandinavica},
          number = {7},
        keywords = {MineralSIP; organic selenium, lamb, ewe, inorganic selenium, blood, slaughter lamb },
        abstract = {Background
Selenium is part of the antioxidant defence system in animals and humans. The available selenium concentration in soil is low in many regions of the world. The purpose of this study was to evaluate the effect of organic versus inorganic selenium supplementation on selenium status of ewes, their lambs, and slaughter lambs.

Methods
Ewes on four organic farms were allocated five or six to 18 pens. The ewes were given either 20 mg/kg inorganic selenium as sodium selenite or organic selenium as selenized nonviable yeast supplementation for the two last months of pregnancy. Stipulated selenium concentrations in the rations were below 0.40 mg/kg dry matter. In addition 20 male lambs were given supplements from November until they were slaughtered in March. Silage, hay, concentrates, and individual ewe blood samples were taken before and after the mineral supplementation period, and blood samples were taken from the newborn lambs. Blood samples from ewes and lambs in the same pens were pooled. Muscle samples were taken from slaughter lambs in March. Selenium concentrations were determined by atomic absorption spectrometry with a hydride generator system. In the ANOVA model, selenium concentration was the continuous response variable, and selenium source and farm were the nominal effect variables. Two-sample t-test was used to compare selenium concentrations in muscle samples from the slaughtered lambs that received either organic or inorganic selenium supplements.

Results
In all ewe pens the whole blood selenium concentrations increased during the experimental period. In addition, ewe pens that received organic selenium had significantly higher whole blood selenium concentrations (mean 0.28 {\ensuremath{\mu}}g/g) than ewe pens that received inorganic selenium (mean 0.24 {\ensuremath{\mu}}g/g). Most prominent, however, was the difference in their lambs; whole blood mean selenium concentration in lambs from mothers that received organic selenium (mean 0.27 {\ensuremath{\mu}}g/g) was 30\% higher than in lambs from mothers that received inorganic selenium (mean 0.21 {\ensuremath{\mu}}g/g). Slaughter lambs that received organic selenium had 50\% higher meat selenium concentrations (mean 0.12 mg/kg wet weight) than lambs that received inorganic selenium (mean 0.08 mg/kg wet weight).

Conclusion
Organic selenium supplementation gave higher selenium concentration in ewe and newborn lamb blood and slaughter lamb meat than inorganic selenium supplementation.

},
             url = {https://orgprints.org/id/eprint/15238/}
}

@inproceedings{orgprints6927,
           title = {Mikromineralinnhold i jord og planter - mikromineralforsyning til dr{\o}vtyggere i {\o}kologisk landbruk},
         journal = {Gr{\o}nn kunnskap},
          volume = {7},
          series = {Gr{\o}nn kunnskap},
          number = {3},
          author = {Turid Str{\o}m and Sissel Hansen and Espen Govasmark},
           pages = {122--137},
            year = {2003},
       publisher = {Planteforsk Kvithamar forskningssenter},
        abstract = {For alle mineralene unntatt klor var det et h{\o}gere innhold i 2. sl{\r a}tt enn i 1. sl{\r a}tt. Flere av plantepr{\o}vene viste s{\r a} lavt innhold av ett eller flere makromineral at det antagelig reduserte avlingsniv{\r a}et. Ut fra mineralbehovet hos sau og storfe viste plante- og blodpr{\o}ver at flere av besetningene hadde liten tilf{\o}rsel av svovel, fosfor, selen og E-vitamin, mens tilf{\o}rselen av magnesium, kobolt og kopper var tilfredsstillende. Videre bearbeidelse av innsamla datamateriell og utpr{\o}ving av ulike selentilskudd til jord og planter vil danne grunnlaget for {\r a} trekke endelig konklusjoner i forskningsprogrammet, samt utarbeide praktiske r{\r a}d om mineraltilf{\o}rsel til planter og dr{\o}vtyggere i {\o}kologisk landbruk. },
             url = {https://orgprints.org/id/eprint/6927/},
        keywords = {Makromineraler, mikromineraler, ku, sau, grovf{\^o}r, jord, mineraltilskudd, {\o}kologisk landbruk, Cu, Se, Cl, Mg, S, P, vitamin E, Co, MINERALSIP}
}