Transport and recycling of radiocesium in the alimentary tract of reindeer

Transport of radiocesium between the body pools and the alimentary tract was studied in 7 reindeer calves. Comparisons were made between reindeer receiving the Cs- binder Prussian blue (Ammon-ium-ironhexacyanoferrate) and untreated animals. The calves were fed lichens contaminated with 134Cs + 137Cs from the Chernobyl accident (about 10 kBq/day) for 4 weeks. Absorption and secretion of radiocesium, Na and K in the alimentary tract were calculated using 51Cr-EDTA as a reference substance. Thirteen sections of the alimentary tract were sampled and analysed for radionuclides and chemical composition. In 4 animals, feeding with contaminated lichens continued until they were slaughtered, whereas in the 3 others the lichen feeding terminated 4 days before slaughter. The activity concentration of Cs nuclides increased 5-17 - fold from duodenum to the distal colon, whereas the concentration of Na decreased and K remained almost constant. Radiocesium, Na and K were secreted into the rumen, the omasum and the abomasum, whereas Na and K also were secreted into the proximal small intestine. Prussian blue had no effect on Na and K recycling, but the flow of radiocesium from the abomasum to the anus and the fecal excretion increased markedly. In the 3 animals where feeding with contaminated lichens was disconutinued 4 days before slaughter, endogenous Cs was continuously recycled between the body pools and the alimentary tract. The net exchange of radiocesium between body pools and the alimentary tract was more than 4 times the amount ingested when lichens were fed. It is concluded that radiocesium is rapidly recycled between the alimentary tract and the other body pools. Cs-binders like ammonium-ironhexacyanoferrate may bind both endogenous Cs and Cs from feed

Hexacyanoferrates and bentonite as binders of radiocaesium for reindeer

The effects of varying doses of caesium binders (Bentonite and several forms of iron-hexacyanoferrates) on radiocaesium accumulation in red blood cells and on radiocaesium transfer to urine and faeces were studied in feeding experiments with reindeer calves. The caesium binders were added to a ration of lichen (containing 9.5 kBq of 134Cs+137Cs originating from the Chernobyl accident) and fed together with a pelleted reindeer feed (RF-71) for 42 days. A 50% reduction in red blood cell radiocaesium concentration was obtained with a daily dose of 1 mg/kg body weigth of ammoniumironhexacyanoferrate (AFCF) and with 500 mg/kg of bentonite. Three mg/kg of AFCF or 2 g/kg of bentonite reduced both urinary excretion and RBC concentrations with more than 80%. It is concluded that iron-hexacyanoferrates, as a result of their high caesium binding capacity, are particularly useful as caesium binders for free ranging ruminants like the reindeer.Hexacynoferrater og bentonitt som bindere av radiocesium i reinAbstract in Norwegian / Sammendrag: Effekten av bentonitt og ulike typer jernhexacyanoferrater (Berlinerblått) på akkumulering av radioaktivt cesium i røde blodlegemer og på utskilling av radioaktivt cesium i urin ble undersøkt i foringsforsøk med reinkalver. Cesiumbinderne ble gitt daglig sammen med lav som inneholdt 9.5 kBq 134Cs+137Cs fra Tsjernobyl ulykken, og 1 kg reinfor (RF-71) i en periode på 42 dager. En daglig dose på 1 mg/kg kroppsvekt av ammoniumjernhexacyano-ferrat (AFCF) reduserte radiocesiuminnholdet i blodlegemer med 50%, mens en dose pa 500 mg/kg bentonitt var nødvendig for å oppnå samme effekt. Tre mg/kg AFCF eller 2 g/kg/bentonitt var nødvendig for å oppnå mer enn 80% reduksjon i radiocesium konsentrasjonen i blodlegemer og i radiocesium utskilling med urinen. På grunn av de små daglige mengder som kreves er jern-hexacyanoferratene spesielt velegnete som cesiumbindere for beitedyr

Variations in the constituent year effect in Junior World Championships in Alpine skiing : A window into relative devolopment effects?

While research on the effects of ‘birth month’ is usually referred to as relative age effects, the study of the effects of ‘birth year’ is described as the constituent year effect (CYE). In the present study we examined the impact of the CYE on participation in the Junior World Championship in alpine skiing. Based on previous research, we expected to find increasing numbers of participants the older the age-group, and that the CYE would be stronger in the speed events compared to the technical ones. The sample in the present study consisted of 1188 male skiers and 859 female skiers within the age range of 17 to 21 years at the time of competition. The results show that the number of male participants increased with increasing age, which can be described as a CYE. For female skiers, a CYE was found, but it dissipated two years earlier than for male skiers. The CYE varied with event and was more pronounced the higher the speed of the event. The findings thus suggest that a constituent year effect exists among skiers participating in the FIS Junior World Ski Championship in the alpine skiing championships, and that the effect varies with gender and event, rather unrelated to age. Thus, it seems that the effect may not be a relative age effect, but instead a relative developmentpublishedVersio

Radiostrontium, radiocesium and stable mineral composition of bones of domestic reindeer from Vågå, Norway

Radiostrontium, radiocesium and macromineral concentrations were measured in metatarsal or metacarpal bones from 78 reindeer (59 calves and 19 adults) in the Vågå reindeer herding district in Southern Norway. Samples were collected in the period August 1988 to May 1989. Radiocesium concentrations increased from August through the winter. Radiostrontium varied slightly around an average value 1810 Bq/kg DM. Mg concentrations decreased through the winter, the concentrations of other minerals and bone density showed only small variations. No signs of mineral deficiencies were observed. It is concluded that radiostrontium mainly originated from the Chernobyl nuclear accident.Radiostrontium, radiocesium og stabile mineraler in reinknokler fra Vågå, NorgeAbstract in Norwegian / Sammendrag: Innhold av radiostrontium, radiocesium og makromineraler ble målt i reinsdyrknokler (metatarsus og metacarpus) innsamlet fra 78 dyr (59 kalver og 19 voksne) tilhørende Vågå tamreinlag. Prøvene ble samlet i perioden august 1988 til mai 1989. Innholdet av radiocesium økte fra august og gjennom vinteren, mens innholdet av radiostrontium var temmelig konstant (1810 Bq/ kg tørrstoff). Magnesium innholdet avtok gjennom vinteren, mens innholdet av andre mineraler samt knoklenes tetthet varierte lite. Det ble ikke observert noen tegn på mineralmangel. Mesteparten av det radioaktive strontium kom fra atomkraftulykken i Tsjernobyl

Effect of sodium and potassium supplementation on accumulation and excretion of radiocaesium in reindeer

We tested the effect of sodium and potassium supplementation on radiocaesium excretion and accumulation in reindeer eating lichens (winter diet). Nine reindeer were divided into 3 groups of 3 animals. One group was daily given 0.35 M KC1, one was given 0.35 M NaCl (both dissolved in 1 1 water), and one group was kept as a control with no mineral supplement. The animals were contaminated with 137Cs from radioactive pasture. During 3 weeks before the experiment the 137Cs concentrations were maintained by daily supplementation of 157Cs sprayed on lichens. From the start of the experimental period the animals received identical large daily doses of I34CsCl. Animals which were given KCl supplementation showed a lower accumulation of 134Cs in red blood cells (RBC) and a faster decrease of 137Cs in RBC than control animals. Sodiumchloride supplementation had no clear effects on radiocaesium concentrations in RBC. Mineral supplements did not affect excretion of radiocaesium via faeces. Supplement of KCl or NaCl increased urine production and the amount of radiocaesium excreted via the urine. It is concluded that increased K intake decreases the radiocaesium concentration in the animals more than is explained by increased urine production alone. This supports the theory that increased K concentration in the diet may contribute to a fast elimination of radiocaesium in reindeer during spring

Effects of administration of potassium- and sodiumchlorides on faecal excretions and salivary and alimentary concentrations of, Na, K, 134Cs, Ca, Mg and P in reindeer fed a lichen diet

A comparison of the effects of administration of 350 mmol d-1 of KC1 or NaCl on faecal excretions, salivary concentrations and concentrations and pools of Na, K, 134Cs, Ca, Mg, P, and water in the alimentary tract of reindeer was carried out using three groups of three 10 months old reindeer fed a lichen diet. One group was used as a control group with no mineral supplementation. The level of K supplementation mimicked K intakes from summer pastures. NaCl was given at a rate which would mimic intake from salt licks by domestic ruminants of similar body size. Treatment with KC1 increased the salivary and alimentary concentrations and the alimentary pool sizes of K and faecal excretion of K increased. A decrease in l34Cs concentrations in all parts of the gastrointestinal tract indicated greater absorption of 134Cs during the KC1 treatment than in NaCl treated and control animals. Increased intake of Na or K had no significant effect on the digestibility of the lichen diet, but urine production increased. Little effects on pools or concentrations of Ca, Mg and P were observed. NaCl treatment increased urinary and faecal excretion of Na, but did not affect the metabolism of any of the other studied minerals

Foam Index measurements on combinations of Air Entraining Agents, Superplasticicers and Fly ash/cement/filler powder mixes

A series of Foam Index measurements were made with 7 different AEAs (abietic acids/resins/tall oil/tensides), 1 copolymer SuperPlaticizer, 2 different Fly Ashes, 1 blended (80/20 OPC/FA) cement, 2 different OPC and 2 inert fillers (limestone and quartz). Foam Index = FI = required dosage of AEA to produce stable foam of a particular binder in a w/p = 2.5 slurry where AEA is added dropwise to a container that is shaken and the foam observed repeatedly until stable foam is obtained. The objective was to investigate the efficiency of the different AEAs with varying Fly Ash binders and the effect of mixing sequence of AEA and SP on the problems encounterd with air entrainment with Fly Ash with variable carbon content. The results show: that the ranking of the FI of the seven AEAs are the same for different OPC/FA binders (with different carbon content); the more carbon the higher the FI, that “tensides” are more robust than “resins”, and that FI in pure OPC binders are very low and not very different for the 7 AEAs. When adding SP before AEA the negative effect of carbon on foaming is reduced for most AEAs, presumably due to adsorption of SP before AEA is introduced in the mix, whereas the FI of some (presumably non-adsorbing) AEAs is not affected by SP addition. For those AEA/FA combinations where the FI is affected by SP, adding SP with the AEA and adding SP after the AEA reduces the efficiency of the AEA. Replacing blended cement with limestone filler and quartz filler seems to affect FI in terms of the specific surface of the filler added: the more surface that is taken away the more efficient becomes the AEA. Foaming with pure wate